Patent Publication Number: US-11045217-B2

Title: Uterine fibroid tissue removal device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. patent application Ser. No. 15/365,502, filed Nov. 30, 2016, now U.S. Pat. No. 10,130,389, which is a continuation of U.S. patent application Ser. No. 14/983,024, filed Dec. 29, 2015, now U.S. Pat. No. 9,539,019, which is a continuation of U.S. patent application Ser. No. 14/680,276, filed Apr. 7, 2015, now U.S. Pat. No. 9,339,288, which is a continuation of U.S. patent application Ser. No. 12/432,686, filed Apr. 29, 2009, now U.S. Pat. No. 9,095,366. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to methods, systems and devices for the removal of tissue and relates more particularly to methods, systems, and devices well-suited for the removal of uterine fibroids and other abnormal gynecological tissues. 
     It is believed that uterine fibroids occur in a substantial percentage of the female population, perhaps in at least 20 to 40 percent of all women. Uterine fibroids are well-defined, non-cancerous tumors that are commonly found in the smooth muscle layer of the uterus. In many instances, uterine fibroids can grow to be several centimeters in diameter and may cause symptoms like menorrhagia (prolonged or heavy menstrual bleeding), pelvic pressure or pain, and reproductive dysfunction. 
     Current treatments for uterine fibroids include pharmacological therapy, hysterectomy, uterine artery embolization, and hysteroscopic resection. Pharmacological therapy typically involves the administration of NSAIDS (non-steroidal anti-inflammatory drugs), estrogen-progesterone combinations, and GnRH (gonadotropin releasing hormone) analogues. However, current pharmacological therapies are largely ineffective and merely palliative. By comparison, a hysterectomy involves the surgical removal of the uterus from a patient. For this reason, a hysterectomy represents a highly effective way of ridding a patient of uterine fibroids. As a result, several hundred thousand hysterectomies are typically performed annually in the United States to treat uterine fibroids. However, despite their widespread use, hysterectomies also possess certain disadvantages, such as a loss of fertility, sexual dysfunction, and the risks commonly associated with a major surgical procedure, such as hemorrhaging, lesions, infections, pain and prolonged recovery. Uterine artery embolization involves inserting a catheter into a femoral artery and then guiding the catheter to a uterine fibroid artery. Small particles are then injected from the catheter into the fibroid artery, blocking its blood supply and causing it to eventually shrink and die. Although this procedure is less invasive than a hysterectomy, it often results in pain-related, post-surgical complications. Moreover, the physicians that are trained to perform uterine artery embolization are typically interventional radiologists, as opposed to physicians trained specifically to take care of gynecological problems, whereas the physicians trained specifically to take care of gynecological problems typically do not possess the skill to perform catheter-based uterine artery embolization. 
     Hysteroscopic resection typically involves inserting a hysteroscope (i.e., an imaging scope) into the uterus through the vagina, i.e., transcervically, and then cutting away the fibroid from the uterus using a device delivered to the fibroid by the hysteroscope. Hysteroscopic resections typically fall into one of two varieties. In one variety, an electrocautery device in the form of a loop-shaped cutting wire is fixedly mounted on the distal end of the hysteroscope—the combination of the hysteroscope and the electrocautery device typically referred to as a resectoscope. The transmission of electrical current to the uterus with a resectoscope is typically monopolar, and the circuit is completed by a conductive path to the power unit for the device through a conductive pad applied to the patient&#39;s skin. In this manner, tissue is removed by contacting the loop with the part of the uterus wall of interest. Examples of such devices are disclosed, for example, in U.S. Pat. No. 5,906,615, inventor Thompson, issued May 25, 1999. 
     In the other variety of hysteroscopic resection, an electromechanical cutter is inserted through a working channel in the hysteroscope. Tissue is then removed by contacting the cutter, which typically has a rotating cutting instrument, with the part of the uterus wall of interest. Examples of the electromechanical cutter variety of hysteroscopic resection are disclosed in, for example, U.S. Pat. No. 7,226,459, inventors Cesarini et al., issued Jun. 5, 2007; U.S. Pat. No. 6,032,673, inventors Savage et al., issued Mar. 7, 2000; U.S. Pat. No. 5,730,752, inventors Alden et al., issued Mar. 24, 1998; U.S. Patent Application Publication No. US 2006/0047185 A1, inventors Shener et al., published Mar. 2, 2006; and PCT International Publication No. WO 99/11184, published Mar. 11, 1999, all of which are incorporated herein by reference. 
     In both of the above-described varieties of hysteroscopic resection, prior to fibroid removal, the uterus is typically distended to create a working space within the uterus. (Such a working space typically does not exist naturally in the uterus because the uterus is a flaccid organ. As such, the walls of the uterus are typically in contact with one another when in a relaxed state.) The conventional technique for creating such a working space within the uterus is to administer a fluid to the uterus through the hysteroscope under sufficient pressure to cause the uterus to become distended. Examples of the fluid used conventionally to distend the uterus include gases like carbon dioxide or, more commonly, liquids like water or certain aqueous solutions (e.g., a saline solution or a sugar-based aqueous solution). Where resection is effected using a resectoscope, it is typically necessary that the distending fluid not be current-conducting so that electricity is not conducted to undesired locations. However, because the distending fluid is administered under pressure (which pressure may be as great as 100 mm Hg or greater), there is a risk, especially when tissue is cut, that the distending fluid may be taken up by a blood vessel in the uterus, i.e., intravasation, which uptake may be quite harmful to the patient. Because excess intravasation can lead to death, it is customary to monitor the fluid uptake on a continuous basis using a scale system. 
     Nevertheless, despite the aforementioned risks of intravasation, with proper monitoring of fluid uptake, hysteroscopic resection is a highly effective and safe technique for removing uterine fibroids. However, one shortcoming with hysteroscopic resection is that it typically requires that anesthesia be administered to the patient. This is because conventional resectoscopes typically have a diameter in excess of 7 mm and because conventional hysteroscopes of the type through which mechanical cutter-type devices are inserted typically have a diameter of about 9 mm. By contrast, the cervix typically cannot be dilated to a diameter greater than about 5.5 mm without causing considerable discomfort to the patient. As a result, due to the need for anesthesia, hysteroscopic resection is typically performed in a hospital operating room and, as a result, bears a large cost due to the setting and the support personnel required. 
     SUMMARY OF THE INVENTION 
     The present invention provides a novel method, system and device for tissue removal. The method, system and device as described above may be used, for example, to remove uterine fibroids and other abnormal gynecological tissues. 
     According to one aspect of the invention, there is provided a tissue removal device, the tissue removal device comprising (a) a housing; (b) an outer tube, the outer tube being fixed to the housing and extending distally therefrom, the outer tube including a resection window; (c) an inner tube disposed within the outer tube, the inner tube being slidable and rotatable relative to the outer tube, the inner tube comprising a distal end; and (d) a drive mechanism for rotating the inner tube relative to the outer tube and, at the same time, for translationally oscillating the inner tube relative to the outer tube so that the distal end of the inner tube rotates while moving back and forth across the resection window, wherein said drive mechanism comprises a drive shaft shaped to include a double helical groove, said drive shaft being translationally stationary. 
     There is provided in accordance with another aspect of the present invention, a tubular cutting element for the tissue removal device of the present invention. The tubular cutting element is adapted for axial reciprocal movement within an outer tubular sleeve, the cutting element having an elongate tubular body having a proximal end, a distal end, and a cutting tip. The tubular body is formed in a drawing operation and the cutting tip is formed in a milling operation. The cutting tip is attached to the tubular body by soldering, brazing, welding, or other attachment technique. 
     In accordance with a further aspect of the present invention, there is provided a tubular cutting element for axial reciprocal movement within an outer tubular sleeve. The cutting element comprises an elongate tubular body, having a proximal end, a distal end and a cutting tip. The tubular body has a Rockwell C hardness of no more than about 40 and the cutting tip has a Rockwell C hardness of at least about 50. The cutting tip may have a Rockwell C hardness of at least about 60, or at least about 70. 
     A coating may be provided in-between the outer tubular sleeve and the inner tubular body. The coating may be applied to either the outer tubular sleeve or the inner tubular body. The coating may comprise a titanium nitride alloy. The coating may comprise a Rockwell C hardness of at least about 50, at least about 60, or at least about 70. 
     Additional aspects, features and advantages of the present invention will be set forth in part in the description which follows. The embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural or process changes may be made without departing from the scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are hereby incorporated into and constitute a part of this specification, illustrate various embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings wherein like reference numerals represent like parts: 
         FIG. 1  is a partially exploded perspective view of a first embodiment of a tissue removal system constructed according to the teachings of the present invention; 
         FIGS. 2( a ) through 2( d )  are various views of the tissue removal device shown in  FIG. 1 , the tissue removal device being shown in  FIGS. 2( a ) through 2( c )  together with the distal ends of the vacuum tube and the external drive shaft; 
         FIG. 3  is a perspective view of the introducer device shown in  FIG. 1 ; 
         FIGS. 4( a ) and 4( b )  are exploded perspective views of the introducer device shown in  FIG. 1 ; 
         FIG. 5  is a right perspective view of the introducer device shown in  FIG. 1 , with the right half of the housing removed; 
         FIG. 6  is a longitudinal section view of the introducer device shown in  FIG. 1 ; 
         FIG. 7  is an enlarged fragmentary perspective view, shown in section, of the introducer device shown in  FIG. 1 , with only the manifold, strain relief and sheath being shown; 
         FIG. 8  is an enlarged distal end view of the multi-lumen sheath of the introducer device shown in  FIG. 1 ; 
         FIG. 9  is an enlarged fragmentary view of the instrument guide assembly of the introducer device shown in  FIG. 1 ; 
         FIGS. 10( a ) and 10( b )  are fragmentary longitudinal section views of alternate inner tubular members that may be used in the tissue removal device shown in  FIG. 1 ; 
         FIG. 11  is a side view of an alternate indicator sleeve that may be used in the tissue removal device shown in  FIG. 1 ; 
         FIG. 12  is a fragmentary side view, partly in section, of an alternate combination of a tissue removal device and an introducer that may be used in the tissue removal system shown in  FIG. 1 ; 
         FIGS. 13( a ) and 13( b )  are fragmentary side views, partly in section, of a further alternate combination of a tissue removal device and an introducer that may be used in the tissue removal system shown in  FIG. 1 ; 
         FIG. 14  is a fragmentary side view, partly in section, of an alternate tissue removal device that may be used in the tissue removal system of  FIG. 1 ; 
         FIGS. 15( a ) and 15( b )  are fragmentary perspective and fragmentary partially exploded perspective views, respectively, of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 1 ; 
         FIG. 16  is a fragmentary side view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 1 ; 
         FIG. 17  is a fragmentary side view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 1 ; 
         FIG. 18  is a fragmentary perspective view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 1 ; 
         FIG. 19  is a fragmentary perspective view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 1 ; 
         FIG. 20  is a fragmentary perspective view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 1 ; 
         FIG. 21  is a fragmentary perspective view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 1 ; 
         FIGS. 22( a ) through 22( e )  are various views of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 1  (the vacuum housing not being shown in  FIGS. 22( c ) through 22( e )  to reveal components positioned therewithin); 
         FIG. 23  is a fragmentary section view of an obturator of the present invention inserted into the introducer shown in  FIG. 1 ; 
         FIG. 24  is a side view of an alternate combination of an obturator and an introducer constructed according to the present invention; 
         FIGS. 25( a ) and 25( b )  are unassembled side and assembled section views, respectively, of another combination of an obturator and an introducer constructed according to the present invention; 
         FIGS. 26( a ) through 26( c )  are fragmentary perspective views of another alternate introducer device to the introducer device shown in  FIG. 1 , with the alternate introducer device being shown in partially exploded states in  FIGS. 26( b ) and 26( c ) ; 
         FIG. 27  is a perspective view of a second embodiment of a tissue removal system constructed according to the teachings of the present invention; 
         FIGS. 28( a ) through 28( d )  are bottom exploded perspective, top exploded perspective, bottom partially exploded, and fragmentary, partly in section, side views, respectively, of the morcellator assembly shown in  FIG. 27 ; 
         FIGS. 29( a ) and 29( b )  are partially exploded top perspective and partially exploded bottom perspective views, respectively, of the drive assembly shown in  FIG. 27 ; 
         FIG. 30  is a fragmentary, partially exploded, perspective view of an alternate tissue removal device that may be used in the tissue removal system of  FIG. 27 ; 
         FIGS. 31( a ) and 31( b )  are fragmentary, partially exploded, perspective views of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 27 ; 
         FIG. 32  is a fragmentary, partially exploded, perspective view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 27 ; 
         FIG. 33  is a fragmentary, partially exploded, perspective view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 27 ; 
         FIG. 34  is a fragmentary section view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 27 ; and 
         FIG. 35  is a fragmentary section view of another alternate tissue removal device that may be used in the tissue removal system of  FIG. 27 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention is described below primarily in the context of devices and procedures optimized for performing one or more therapeutic or diagnostic gynecological or urological procedures such as the removal of uterine fibroids or other abnormal uterine tissue. However, the devices and related procedures of the present invention may be used in a wide variety of applications throughout the body, through a variety of access pathways. 
     For example, the devices of the present invention can be optimized for use via open surgery, less invasive access such as laparoscopic access, or minimally invasive procedures such as via percutaneous access. In addition, the devices of the present invention can be configured for access to a therapeutic or diagnostic site via any of the body&#39;s natural openings to accomplish access via the ears, nose, mouth, and via trans-rectal, urethral and vaginal approach. 
     In addition to the performance of one or more gynecological and urologic procedures described in detail herein, the systems, methods, apparatus and devices of the present invention may be used to perform one or more additional procedures, including but not limited to access and tissue manipulation or removal from any of a variety of organs and tissues such as the bladder, breast, lung, stomach, bowel, esophagus, oral cavity, rectum, nasal sinus, Eustachian tubes, heart, gall bladder, spine, shoulder, knee, hip, brain, arteries, veins, and various ducts. Routes of access include but are not limited to trans-cervical; trans-vaginal-wall; trans-uteral; trans-vesicle; trans-urethral; and other routes. 
     Referring now to  FIG. 1 , there is shown a partially exploded perspective view of one embodiment of a tissue removal system, the tissue removal system being constructed according to the teachings of the present invention and being represented generally by reference numeral  5 . 
     System  5  is particularly well-suited for removing uterine fibroids and other abnormal gynecological tissues. However, it should be understood that system  5  is not limited to such a use and may be used in other anatomies that may be apparent to those of ordinary skill in the art. 
     System  5  may comprise a tissue removal device (or morcellator)  6 , an introducer device  7 , a flexible hysteroscope  8 , a fluid supply  9 , a vacuum assembly  10 , and a motor drive assembly  11 . 
     Referring now to  FIGS. 2( a ) through 2( d ) , tissue removal device  6  may be seen in greater detail. Device  6  may comprise complementary left and right housing halves  13 - 1  and  13 - 2 , respectively, each of which may be made of a rigid polymer or other suitable material. Halves  13 - 1  and  13 - 2  may be joined together, for example, with screws  15  to form an elongated hollow housing  13  comprising a rounded side wall  16 , an open proximal end  17 , and an open distal end  19 . Housing  13  may be bent or otherwise ergonomically shaped to fit comfortably in the hand of a user. A proximal cap  18  may be mounted in proximal end  17 , cap  18  being shaped to include a pair of lumens  18 - 1  and  18 - 2 . Lumen  18 - 1  may be used to receive, for example, an external drive shaft, and lumen  18 - 2  may be used to receive, for example, a vacuum tube. A distal cap  20  may be mounted in distal end  19 , cap  20  being shaped to include a lumen, which may be used to receive, for example, a pair of coaxial cutting tubes. 
     A plurality of ribs  14  may be integrally formed and appropriately positioned along the respective interior surfaces of halves  13 - 1  and  13 - 2 , ribs  14  providing structural reinforcement to housing  13  and being used to align certain of the mechanical components that are positioned within housing  13 . 
     Device  6  may further comprise an internal drive shaft  21  adapted for rotation about its longitudinal axis. Shaft  21 , which may be an elongated unitary structure made of a suitably rigid metal or polymer, may be shaped to include a proximal end  23  and a distal end  25 . Proximal end  23  of shaft  21  may be coaxially mounted over and fixed to the distal end  27  of an external drive shaft  29 , external drive shaft  29  being inserted through a retainer  28  mounted in housing  13 . In this manner, the rotation of shaft  21  may be mechanically coupled to the rotation of shaft  29 . Distal end  25  of shaft  21  may be inserted through an opening  30  in an annular bushing  31 , which bushing  31  may be matingly mounted on a rib  14 - 1  via a circumferential slot  32  provided in bushing  31 . 
     Device  6  may further comprise a translation drive shaft  35  adapted for rotation about its longitudinal axis. Shaft  35 , which may be an elongated unitary structure made of a suitably rigid metal or polymer, may be shaped to include a proximal end  37 , an intermediate portion  39 , and a distal end  41 . Proximal end  37  of shaft  35  may be coaxially mounted over and fixed to the distal end  25  of internal drive shaft  21 . In this manner, the rotation of shaft  35  may be mechanically coupled to the rotation of shaft  21 . Intermediate portion  39  may be shaped to include a double helical portion comprising a right-handed threaded helical channel  42  and a left-handed threaded helical channel  43 . Helical channels  42  and  43  may have identical or different pitches but preferably have identical pitches. Helical channels  42  and  43  may be smoothly blended together at their respective ends to form a continuous groove so that there may be a smooth transition from one helical channel to the other. Distal end  41  of shaft  35  may be appropriately dimensioned to be received within an opening  44  in an annular bushing  45 , which bushing  45  may be matingly mounted on a rib  14 - 2  via a circumferential slot  46  provided in bushing  45 . It should be noted that, although shaft  35  is adapted for rotation, shaft  35  is translationally stationary. 
     Device  6  may further comprise a gear assembly  50  adapted for rotation about its longitudinal axis. Gear assembly  50 , which may be an elongated unitary structure made of a suitably rigid metal or polymer, may be shaped to include a proximal spur gear  51  and a distal tube portion  52 . Gear assembly  50  may be coaxially mounted over intermediate portion  39  of shaft  35  in an area between the double helical portion and distal end  41 , and gear assembly  50  may be fixed to shaft  35  using a pin inserted radially through tube portion  52  and into an opening provided in shaft  35 . In this manner, the rotation of spur gear  51  may be mechanically coupled to the rotation of shaft  35 . 
     Device  6  may further comprise an oscillating translation assembly  61 . Translation assembly  61 , in turn, may comprise a carriage  62  and a channel engagement member  63 . Carriage  62 , which may be a unitary structure made of a suitably rigid metal or polymer, may be shaped to include a proximal portion  64 , an intermediate portion  65 , and a distal portion  66 . The tops of proximal portion  64  and distal portion  66  may extend beyond the top of intermediate portion  65  and may be shaped to include loops  67 - 1  and  67 - 2 , respectively, loops  67 - 1  and  67 - 2  being aligned with one another. A longitudinal bore  68 - 1  may be provided near the bottom of carriage  62 , bore  68 - 1  being appropriately dimensioned to coaxially receive intermediate portion  39  of shaft  35  while permitting intermediate portion  39  to rotate freely therewithin. Channel engagement member  63 , which may be a unitary structure made of a suitably rigid metal or polymer, may be shaped to include a base  69  and a pawl  70 . Base  69  may be disposed in an opening  68 - 2  that may extend downwardly from the top of intermediate portion  65  into communication with bore  68 - 1 , with pawl  70  traveling within the double helical portion of shaft  35 . In this manner, as shaft  35  rotates, pawl  70  may continuously travel back and forth through the double helical portion of shaft  35 , thereby causing carriage  62  to oscillate translationally. As can be appreciated, the speed at which carriage  62  oscillates translationally may be varied, for example, by varying the translational length of the double helical portion of shaft  35 , the angles of channels  42  and  43 , the rotational speed of shaft  29 , etc. As will be discussed further below, it may be desirable to operate device  6  so that carriage  62  oscillates translationally at about 2.8 cycles/second. 
     Device  6  may further comprise a shaft  72  adapted for rotation about its longitudinal axis. Shaft  72 , which may be an elongated, unitary, tubular structure made of a suitably rigid metal or polymer, may be shaped to include a proximal portion  72 - 1  and a distal portion  72 - 2 . Proximal portion  72 - 1  may be inserted through loops  67 - 1  and  67 - 2  of carriage  62  and may freely rotate relative to loops  67 - 1  and  67 - 2 . Distal portion  72 - 2  may be in the form of an elongated spur gear. Distal portion  72 - 2  may be engaged with spur gear  51  of gear assembly  50  so that the rotation of spur gear  51  causes the rotation of shaft  72 . Distal portion  72 - 2  may be elongated so that it may maintain engagement with spur gear  51  even as distal portion  72 - 2  moves translationally relative to spur gear  51 . The speed at which distal portion  72 - 2  rotates (and, therefore, the speed at which shaft  72  rotates) may be the same as or different than the speed at which spur gear  51  rotates, depending, for example, on the relative diameters of the two gears (the ratio of the rotational speeds of the two gears being inversely proportional to the ratio of the diameters of the two gears). Consequently, by appropriately dimensioning spur gear  51  and distal portion  72 - 2 , one can achieve a desired rotational speed, even where the rotational speed of the external drive shaft is fixed. For example, in the embodiment shown, distal portion  72 - 2  has a diameter that is one-fourth the diameter of spur gear  51  and, therefore, rotates four times as fast as gear  51 . Therefore, if the external drive shaft has a speed of rotation of about 1500 rpm, gear  51  would rotate at 1500 rpm and distal portion  72 - 2  would rotate at 6000 rpm. As can be appreciated, the rotational speed of distal portion  72 - 2  does not depend on the interaction of translation assembly  61  with the double helical portion of shaft  35 ; consequently, distal portion  72 - 2  may attain higher or lower rotational speeds than would be possible based on the requirements of a desired translational speed. Notwithstanding the above, shaft  72  is translationally coupled to carriage  62 . Consequently, as carriage  62  oscillates translationally, so does shaft  72 . 
     Device  6  may further comprise a strain relief member  74 , which may be a unitary tubular structure made of a rigid polymer or metal. The proximal end of strain relief member  74  may be fixedly mounted in a retainer  75 , which may be mounted at the distal end of housing  13 , with the distal end of strain relief  74  extending distally from housing  13  for a short distance, such as, for example, approximately 2 inches. 
     Device  6  may further comprise a cutting mechanism. In the present embodiment, the cutting mechanism may comprise an outer tubular member  76  and an inner tubular member  77 , inner tubular member  77  moving rotationally and, at the same time, oscillating translationally relative to outer tubular member  76  in the manner to be described further below. Outer tubular member  76 , which may be a unitary structure made of stainless steel or another similarly suitable material, may be shaped to include an open proximal end, a closed distal end  81 , and a lumen  82  extending from open proximal end  79  to a point just prior to closed distal end  81 . Member  76  may be coaxially mounted within strain relief member  74 , with the proximal end of member  76  disposed within the proximal end of strain relief member  74  and with distal end  81  of member  76  extending distally beyond the distal end of strain relief member  74  for an extended distance, such as, for example, five inches. The proximal end of member  76  may be fixed within retainer  75 . 
     Outer tubular member  76  may be further shaped to include a resection window  89  into which tissue may be captured and drawn, window  89  being located proximate to distal end  81 , such as, for example, 0.25 inch from distal end  81 . Window  89  may be shaped to include a proximal end  89 - 1  and a distal end  89 - 2 . Proximal end  89 - 1  may slope gradually proximally, and distal end  89 - 2  may slope gradually distally. More specifically, window  89  may have a length of approximately 0.55 inch, proximal end  89 - 1  may be a radial end having a radius of curvature of, for example, 0.085 inch, and distal end  89 - 2  may be a radial end having a radius of curvature of, for example, 0.150 inch. Window  89  may extend over a substantial portion of the circumference of tubular member  76 , such as, for example, about 60% of the circumference. 
     Outer tubular member  76  may have an outer diameter less than about 5.5 mm. However, in order to reduce the risk of injury to the patient and in order to obviate the need for anesthesia to be administered to the patient, outer tubular member  76  preferably has an outer diameter less than about 5 mm, more preferably less than 4 mm, even more preferably less than 3 mm, and still even more preferably less than 2 mm. However, should device  6  be used in an operating room setting where general anesthesia is available, the diameter of the outer tubular member  76  could be increased to maximize tissue removal. In such a case, outer tubular member  76  could have a diameter generally less than about 12 mm, preferably less than about 11 mm, and for certain applications less than 10 mm. Depending on the particular clinical application, outer tubular member  76  could be constructed having an outer diameter of no more than about 9 mm, in some applications less than about 8 mm, preferably less than 7 mm, and more preferably less than 6 mm where OD is desirably minimized. 
     Inner tubular member  77 , which may be an elongated unitary structure made of stainless steel or another similarly suitable material, may be shaped to include a proximal end  91 , a distal end  92 , and a longitudinal lumen  93 . Distal end  92  may be shaped to include an external bevel, such as, for example, an external bevel of approximately 20 degrees. An intermediate length of tubular member  77  may be coaxially received within shaft  72  and may be fixedly coupled to shaft  72  for translational and rotational movement therewith. Proximal end  91  of tubular member  77  may be slideably mounted within a vacuum tube connector  95 , which may, in turn, be coupled to a vacuum tube  393  inserted through lumen  18 - 2  of cap  18 . An O-ring  96  may be mounted within connector  95  to maintain a good seal with tubular member  77 . An annular bushing  98  mounted within housing  13  may be used to receive tubular member  77  and to maintain its alignment. 
     Tubular members  76  and  77  may be arranged so that, when tubular member  77  is in a fully retracted (i.e., proximal) position, distal end  92  of tubular member  77  may be withdrawn sufficiently to permit tissue to enter window  89  (preferably with distal end  92  of tubular member positioned proximal to window  89 ), and so that, when tubular member  77  is in a fully advanced (i.e., distal) position, distal end  92  of tubular member  77  may be positioned distally of distal end  89 - 2  of window  89 . In this manner, as tubular member  77  is moved translationally and rotationally past window  89 , tissue within window  89  may be sheared. To promote such a shearing of tissue, the outer diameter of inner tubular member  77  may be just slightly less (e.g., about 0.002 inch) than the inner diameter of outer tubular member  76 . 
     It has been shown that the thermal energy created by the contact of the rotating inner tube  77  and outer tube  76  can lead to galling where the two tubular members fuse together. To mitigate that galling risk, the outer surface of inner tube  77  has been covered with a low friction, low abrasion coating (i.e., Titanium Nitride). Alternatively, the coating can be carried by the inner surface of the outer tube  76 . The coating may have a Rockwell C hardness of at least about 50, preferably at least about 60 and in some devices at least about 70. 
     Device  6  may further comprise an indicator sleeve  98 . Sleeve  98 , which may be an elongated tubular member made of a material that is easily distinguishable visually from strain relief member  74 , may be coaxially mounted over strain relief member  74  and fixedly mounted thereto, with a proximal end  98 - 1  of sleeve  98  lying flush against the distal end of housing  13 . An example of a material suitable for use as sleeve  98  may be a white or colored length of shrink-wrap material. Sleeve  98  may be dimensioned so that, when device  6  is inserted into introducer device  7 , distal end  98 - 2  of sleeve  98  is visible to a user until distal end  81  of device  6  is advanced beyond the distal end of introducer  7 . In other words, distal end  98 - 2  may be used to indicate when distal end  81  of device  6  lies flush with the distal end of introducer  7 . In this manner, a user may safely control the position of the distal end of device  6  and, therefore, keep it within introducer  7  when inserting device  6  into a patient, thereby reducing the risks for lacerations and perforations during introduction of device  6 . 
     Referring now to  FIGS. 3 through 7 , introducer  7  may comprise a housing  121 . Housing  121 , in turn, may comprise a left handle half  123  and a right handle half  125 . Left handle half  123  and right handle half  125 , which may be molded or otherwise fabricated from a rigid polymer or other suitable material, may be joined by a plurality of screws  127 . Instead of being joined by screws  127 , left handle half  123  and right handle half  125  may be joined using a suitable adhesive, crush pins, or may be welded together ultrasonically or otherwise. Left handle half  123  and right handle half  125  jointly define a hollow, gun-shaped structure comprising a handle portion  129  and a barrel portion  131 . Handle portion  129  may be shaped to include an opening  133  provided at its bottom end  134  and an opening  135  provided along its distal face  136  near bottom end  134 . A slot  133 - 1  may be provided in right handle half  125 , slot  133 - 1  extending from opening  133  towards barrel portion  131  for a short distance. Barrel portion  131  may be shaped to include an opening  137  provided at its proximal end  138  and an opening  139  provided at its distal end  140 . In addition, barrel portion  131  may be shaped to include a transverse opening  141  provided in right handle half  125  at a location intermediate to proximal end  138  and distal end  140 . 
     The interior surfaces of left handle half  123  and right handle half  125  may shaped to include complementary sets of ribs (not shown). Such ribs may provide structural reinforcement to left handle half  123  and right handle half  125  and may help to maintain the correct positioning and alignment of the components positioned within housing  121 . 
     Introducer  7  may further comprise a manifold  145 . Manifold  145 , which may be molded or otherwise fabricated from a rigid polymer or other suitable material, may be a unitary, branched structure shaped to include a main tubular member  147  and a side tubular member  149 . Main member  147  may comprise a proximal end  151 , an open distal end  153 , a side wall  155 , and a longitudinal lumen  157 . Proximal end  151  of main member  147  may be shaped to include a top opening  159  of comparatively greater diameter and a bottom opening  161  of comparatively smaller diameter. Side member  149  may comprise an open proximal end  163 , an open distal end  165 , a side wall  167 , and a longitudinal lumen  169 . Lumen  169  of side member  149  may be in fluid communication with lumen  157  of main member  147  through open distal end  165 . 
     Manifold  145  may be coupled to housing  121  using a pair of pins  171  and  173  that may extend from side wall  155  and that may be received within hollow embossments  175  and  177 , respectively, provided on the interior faces of left handle half  123  and right handle half  125 , respectively. With manifold  145  thus coupled to housing  121 , proximal end  151  of manifold  145  may be positioned in barrel portion  131 , with side wall  155  tightly fitting within opening  139  and with distal end  153  of manifold  145  extending distally a short distance beyond distal end  140 . 
     Introducer  7  may further comprise a strain relief member  181 . Strain relief member  181 , which may be molded or otherwise fabricated from a rigid polymer or other suitable material, may be a unitary tubular structure shaped to include an open proximal end  183 , an open distal end  185 , a side wall  187 , and a longitudinal lumen  189 . Strain relief member  181  may be partially inserted into lumen  157  of manifold  145  and may be tightly fitted within lumen  157  and fixedly secured thereto using a suitable adhesive or the like, with proximal end  183  of strain relief member  181  being positioned just distal to open distal end  165  of side member  149  and with distal end  185  of strain relief member  181  extending distally a short distance beyond distal end  153  of main member  147 . 
     Introducer  7  may further comprise a sheath  191 , which is also shown separately in  FIG. 8 . Sheath  191 , which may be extruded or otherwise fabricated from a suitable polymer, such as nylon 12, may be a rigid, unitary structure shaped to include a proximal end  192 , a distal end  193 , and a side wall  194 . Sheath  191  may be further shaped to include a plurality of longitudinal lumens of fixed shape and size, such lumens including a top lumen  196 , a bottom lumen  197 , and a pair of side lumens  198 - 1  and  198 - 2 . As will be discussed further below, top lumen  196  may be used as an instrument lumen, bottom lumen  197  may be used as a visualization lumen, and side lumens  198 - 1  and  198 - 2  may be used as inflow fluid supply lumens. (Openings (not shown) may be provided in side wall  194  proximate to distal end  193 , such side openings fluidly communicating with side lumens  198 - 1  and  198 - 2 , for example, to dispense some of the inflow fluid supply conducted distally through side lumens  198 - 1  and  198 - 2 .) Proximal end  192  of sheath  191  may be partially inserted into lumen  189  of strain relief member  181  and may be tightly fitted within lumen  189  and fixedly secured thereto using a suitable adhesive or the like, with proximal end  192  of sheath  191  flush with proximal end  183  of strain relief member  181  and with distal end  193  of sheath  191  extending distally beyond distal end  185  of strain relief member  181  for several inches. 
     Sheath  191 , which is preferably the only component of introducer  7  that is to be inserted into a patient, may be dimensioned to have an outer diameter of about 5.5 mm, with lumen  196  having a diameter of about 3 mm, lumen  197  having a diameter of about 2 mm, and lumens  198 - 1  and  198 - 2  each having a diameter of about 1.33 mm. It can be further stated the ratio of the outer diameter to the working channel is an exemplary metric of introducer efficiency. It can be seen that the optimal ratio would be about 1.0, preferably no more than about 2.1 and more preferably no more than about 1.9. In the case provided herein, the ratio of these diameters is about 1.83 while predicate systems have ratios of 2.25. By thus dimensioning sheath  191 , if sheath  191  is inserted through the cervix of a patient, the risk of injury to the patient and the need for anesthesia to be administered to the patient may be minimized. However, it should be understood that the above dimensions for sheath  191  are merely exemplary and may be varied depending upon how introducer  7  is to be used. 
     Introducer  7  may further comprise an instrument guide assembly mounted within housing  121  for providing a continuous channel aligned with lumen  196  into which tissue removal device  6  may be inserted. The instrument guide assembly may comprise a guide body  201 . Body  201 , which may be molded or otherwise fabricated from a rigid polymer or other suitable material, may be a unitary tubular structure shaped to include a proximal portion  203 , a distal portion  205  and an intermediate portion  207 . Intermediate portion  207  may be reduced in inner diameter and in outer diameter relative to proximal portion  203  and distal portion  205  so that an annular seat  208  is formed within body  201  at the juncture of intermediate portion  207  and distal portion  205 . The interior surface of body  201  may taper inwardly from proximal portion  203  to intermediate portion  207  to facilitate insertion of device  6  into intermediate portion  207  and to delimit the extent to which device  6  may be inserted into body  201 . 
     Body  201  may be tightly fitted within opening  137  of housing  121  and fixedly secured thereto using a suitable adhesive or the like, with distal portion  205  and intermediate portion  207  of body  201  being positioned within barrel portion  131  of housing  121  and with proximal portion  203  of body  201  extending through opening  137  and continuing proximally for a short distance beyond proximal end  138  of housing  121 . 
     The instrument guide assembly may further comprise a sleeve  211 . Sleeve  211 , which may be molded or otherwise fabricated from a rigid polymer or other suitable material, may be a unitary, branched structure shaped to include a main tubular member  213  and a side tubular member  215 . Main member  213  may comprise an open proximal end  216 , an open distal end  217 , and a longitudinal lumen  219 . Proximal end  216  of main member  213  may be shaped to be tightly fitted within distal portion  205  of body  201  and may be bonded thereto using a suitable adhesive. Side member  215  may comprise an open proximal end  220 , an open distal end  221  and a longitudinal lumen  223 . Lumen  223  of side member  215  may be in fluid communication with lumen  219  of main member  213  through open proximal end  220 . Distal end  221  of side member  215  may extend through opening  141  provided in right handle half  125  of housing  121  and may be coupled to a valve  228 . Valve  228  may be an actively-controlled valve, such as a stopcock valve, or a passively-controlled valve, such as a spring-activated ball valve. Valve  228  may be connected at its output end to a length of tubing (not shown), as well as to a fluid receptacle (not shown), for conducting, as well as collecting, for example, outflow fluid passing through valve  228 , for example, when device  6  is not present within introducer  7 . 
     The instrument guide assembly may further comprise the combination of a seal  231  and a valve  233 . Seal  231  and valve  233  may be elastomeric members securely positioned between seat  208  of body  201  and proximal end  216  of sleeve  211  (see  FIG. 9 ). Seal  231 , which may be located proximally relative to valve  233 , may include a central opening  235 . Opening  235  may be appropriately dimensioned so that, when device  6  is inserted therethrough, fluid may not readily pass proximally through seal  231  around the outside of device  6 . Valve  233 , which may be shaped to include a dome having a cross-slit at its top, may be designed so that, in the absence of device  6  being inserted therethrough, fluid may not readily pass proximally therethrough. 
     The instrument guide assembly may further comprise a tube  241 . Tube  241 , which may be a rigid hypotube made of stainless steel or the like, may comprise a proximal end  243  and a distal end  245 . Proximal end  243  may be fixedly mounted within lumen  219  of sleeve  211  using a suitable adhesive or the like. Distal end  245  of tube  241  may be tightly fitted within lumen  196  of sheath  191  and may be secured therewithin using a suitable adhesive or the like. 
     Introducer  7  may further comprise a visualization guide assembly mounted within housing  121  for providing a continuous channel aligned with lumen  197  into which hysteroscope  8  may be inserted. The visualization guide assembly may comprise a guide body  251 . Body  251 , which may be molded or otherwise fabricated from a rigid polymer or other suitable material, may be a unitary tubular structure shaped to include a proximal portion  253  of comparatively greater diameter, a distal portion  255  of comparatively smaller diameter, and an intermediate portion  257  tapering in diameter from proximal portion  253  to distal portion  255 . Body  251  may be disposed within handle portion  129  of housing  121 , with proximal portion  253  spaced inwardly a short distance from opening  133  and with distal portion  255  facing towards barrel portion  131 . Proximal portion  253  may be tightly fitted between and fixedly secured to left handle half  123  and right handle half  125  of housing  121  using adhesive or other suitable means. As will be discussed further below, proximal portion  253  may be appropriately dimensioned to receive the proximal portion of hysteroscope  8 , with intermediate portion  257  of body  251  being appropriately dimensioned to serve as a stop to limit the extent to which hysteroscope  8  may be inserted into body  251 . An annular seat  258  may be provided within distal portion  255  and may be spaced proximally relative to distal end  259  of distal portion  255 . 
     The visualization guide assembly may further comprise a guide connector  261 . Guide connector  261 , which may be molded or otherwise fabricated from a rigid polymer or other suitable material, may be a unitary tubular structure shaped to include a proximal portion  263  of comparatively greater diameter, a distal portion  265  of comparatively smaller diameter, and an intermediate portion  267  tapering in diameter from proximal portion  263  to distal portion  265 . Proximal portion  263  may be shaped to be tightly fitted within distal portion  255  of body  251  and may be bonded thereto using a suitable adhesive. 
     The visualization guide assembly may further comprise the combination of a seal  271  and a valve  273 . Seal  271  and valve  273  may be elastomeric members securely positioned between seat  258  of body  251  and proximal portion  263  of connector  261 . Seal  271 , which may be located proximally relative to valve  273 , may include a central opening appropriately dimensioned so that, when hysteroscope  8  is inserted therethrough, fluid may not readily pass proximally through seal  271  around the outside of hysteroscope  8 . Valve  273 , which may be shaped to include a dome having a cross-slit at its top, may be designed so that, in the absence of hysteroscope  8  being inserted therethrough, fluid may not readily pass proximally therethrough. 
     The visualization guide assembly may further comprise a tube  281 . Tube  281 , which may be a flexible unitary member fabricated from a suitable polymer or other material, may comprise a proximal end  283 , a distal end  285 , and a lumen  286 . Proximal end  283  may be fixedly mounted within distal portion  265  of connector  261  using a suitable adhesive or the like. Distal end  285  of tube  281  may be tightly fitted within lumen  197  of sheath  191  and may be secured therewithin using a suitable adhesive or the like. Lumen  286  may be appropriately dimensioned so that the distal portion of hysteroscope  8  may be inserted thereinto and, in this manner, guided by tube  281  to lumen  197 . 
     Introducer  7  may further comprise a mechanism for reversibly coupling hysteroscope  8  to the visualization guide assembly. This mechanism may comprise a cam lock  291 . Lock  291 , which may be fabricated from a rigid polymer or other suitable material, may be a unitary structure shaped to comprise a lever  292  and a fulcrum  293 . The fulcrum  293  may be pivotally mounted on housing  121  using a pivot pin  294  inserted through a transverse opening  295  in fulcrum  293  and securely received at its opposite ends in openings  296  and  297  provided in left handle half  123  and right handle half  125 , respectively. Fulcrum  293  may comprise a face  298  adapted to frictionally engage the proximal portion of hysteroscope  8  when lever  292  is pivoted towards handle portion  129 . 
     Introducer  7  may further comprise a tube  301 . Tube  301 , which may be fabricated from a suitable polymer or other material, may be a flexible unitary structure shaped to include a proximal end  303  and a distal end  305 . Proximal end  303  may be secured to the distal end of a luer fitting  307  securely mounted within opening  135  of housing  121 . Distal end  305  may be positioned within lumen  169  of manifold  145  and may be secured in place using an adhesive or other suitable means. As will be discussed further below, luer fitting  307  may be connected to the output of fluid supply  9 . In this manner, fluid dispensed through fitting  307  and into tube  301  may be conducted by tube  301  to manifold  145 . Thereafter, the fluid in manifold  145  may flow distally through lumens  198 - 1  and  198 - 2  of sheath  191 . 
     Referring back now to  FIG. 1 , hysteroscope  8 , which may be, for example, a conventional flexible hysteroscope, may comprise a proximal portion  311  and a distal portion  313 . Proximal portion  311 , which may be comparatively rigid, compact in length, and wide in diameter, may comprise an input port  315 , an output port  317 , and a distal end  318 . Distal portion  313 , which may be comparatively flexible, elongated in length, and narrow in diameter, may comprise a distal end  319 . Hysteroscope  8  may be appropriately dimensioned so that distal end  318  of proximal portion  311  may be received in body  251 , with distal portion  313  extending distally through seal  271 , valve  273 , connector  261 , tube  281  and lumen  197  and with distal end  319  positioned at or a short distance beyond distal end  193  of sheath  191 . Although not present in the embodiment shown, proximal portion  311  of hysteroscope  8  may be provided with notches or other physical features that may be used to mate with or otherwise engage cam lock  291 . Distal end  319  of hysteroscope  8  may be constructed to permit the viewing of objects, such as at 0, 15 or 30 degree angles, relative to the longitudinal axis of distal portion  313 . In this manner, by placing hysteroscope  8  in a particular angular orientation, hysteroscope  8  may be used to view the operation of the distal end of device  6 . Such an angular orientation may be ensured by orienting hysteroscope  8  so that input port  315  is aligned with and extends through slot  133 - 1 . 
     Fluid supply  9  may comprise a fluid-containing syringe, a peristaltic pump or another suitable fluid-dispensing device having an output end  321  that may be coupled to luer fitting  307 . Fluid supply  9  may comprise automated means (not shown) for dispensing inflow fluid therefrom at a desired rate. 
     Vacuum assembly  10  may include a specimen collection container  391  and a vacuum source  392 . The distal end of an evacuation tube  393  may be connected to the proximal end of vacuum tube connector  95 , and the proximal end of evacuation tube  393  may be coupled to a first port  394  of container  391 . The distal end of a tube  395  may be coupled to a second port  396  of container  391 , and the proximal end of tube  395  may be coupled to vacuum source  392 . In this manner, vacuum source  392  may be used to apply suction to device  6 , and any withdrawn tissue, liquids or similar matter suctioned through device  6  may be collected in container  391 . 
     Motor drive assembly  11 , which may be coupled to a source of electricity, such as an AC wall outlet, using a power cord (not shown), may include a housing  397 , in which there may be disposed electronics (not shown) and a motor (not shown). A foot pedal  398  may be coupled to the motor drive assembly by a cable  398 - 1  and may be used as a power switch to selectively activate or de-activate the motor. The proximal end of shaft  29  may be mechanically coupled for rotation to the motor, and the distal end of shaft  29  may be inserted through opening  18 - 1  in mounting block  18  and coupled to internal shaft  21  in the manner discussed above. A protective sheath  399  may cover much of the length of shaft  29 . Motor drive assembly  11  may further include a vacuum sensor  400 , which may be coupled to container  391  by a tube  401 , so that the pressure within container  391  may be monitored. In this manner, a sudden increase in vacuum pressure may indicate that a clog has occurred. The presence of a clog may be indicated via an alarm (not shown) located on housing  397 . The detection of a clog is often a clear indication that the further operation of device  6  may only aggravate the clogging situation and that a cessation of tissue removal may be necessary. Motor drive assembly  11  may be configured to synchronize actuation of the motor with actuation of vacuum source  392 . In this manner, turning on the motor will turn on vacuum source  392  at the same time. Correspondingly, vacuum source  392  may be deactivated whenever the motor is turned off. 
     In use, distal end  319  of hysteroscope  8  may be inserted first through the visualization guide channel of introducer  7 , next through manifold  145 , and then through lumen  197  of sheath  191 . With hysteroscope  8  thus inserted into introducer  7 , cam lock  291  may be used to secure proximal portion  311  of hysteroscope  8  to introducer  7 . Input end  315  and output end  317  of hysteroscope  8  may then be coupled to a light source and to a camera, respectively. Alternatively, the camera may be omitted, and output end  317  may be observed directly with the unaided eye. Fluid supply  9  may then be coupled to luer fitting  307  of introducer  7 . Distal end  193  of sheath  191  may then be inserted transcervically, i.e., through the vagina and the cervix, into the uterus of the patient. Prior to introducing distal end  193  of sheath  191  into the patient, the cervix may be gradually dilated in the conventional manner using obturators of increasing diameter. The uterus may then be washed of blood and other debris that may be present by dispensing fluid from fluid supply  9  into introducer  7 , which fluid may then exit introducer  7  distally through lumens  198 - 1  and  198 - 2 . Valve  228  may be opened during this washing procedure so that fluid and any debris present in the uterus may exit the uterus proximally through lumen  196  of sheath  191  and, thereafter, may exit introducer  7  by passing proximally through tube  241 , into main member  213  of sleeve  211 , through side member  215  of sleeve  211 , and through valve  228 . When the washing procedure is complete, valve  228  may be closed while fluid may continue to be dispensed into the uterus through lumens  198 - 1  and  198 - 2 , thereby causing the uterus to become distended by the fluid. When the uterus becomes sufficiently distended by such fluid, valve  228  may be opened while fluid may continue to be dispensed into the uterus. In this manner, the uterus may be maintained at a desired degree of distension while fluid is continuously circulated through the uterus. With the uterus thus distended with fluid, hysteroscope  8  may be used to examine the interior of the uterus. 
     If abnormalities are detected that one wishes to remove, tissue removal device  6  may be loaded into introducer  7 , i.e., by inserting the distal ends of outer tubular member  76  and inner tubular member  77  distally through the instrument channel guide of introducer  7  and then through channel  196  of sheath  191 , with housing  13  remaining external to the patient. Device  6  may then be manipulated so that window  89  of outer tubular member  76  may be positioned in proximity to the fibroid or other targeted tissue. Next, vacuum source  392  may be operated so as to cause suction to be applied to inner tubular member  77 , thereby drawing tissue into outer tubular member  76  through window  89 . In addition, the motor of motor drive assembly  11  may be actuated, thereby causing inner tubular member  77  simultaneously to rotate and to oscillate back and forth translationally within outer tubular member  76 , resulting in the tissue drawn through window  89  to be cut. The cut tissue may then be suctioned from the patient through inner tubular member  77  by means of the aforementioned suction and, thereafter, collected in container  391 . Once the fibroids or other targeted tissues have thus been removed from the patient, vacuum source  392  and the motor may be turned off, device  6  may be withdrawn from introducer  7 , and introducer  7  may be withdrawn from the patient. Device  6  may be designed to be a single use device. If so, device  6  may then be disconnected from evacuation tube  393  and flexible motor shaft  398 - 2  and disposed of properly. 
     It should be noted that, although the above-discussion contemplates using introducer  7  to introduce device  6  into the uterus, one may insert device  6  transcervically into the uterus without the use of introducer  7 . In such a situation, fluid may be administered transcervically to the uterus by a fluid dispensing device in order to distend the uterus, and, thereafter, observation of the uterus may be accomplished, for example, by ultrasonic imaging using an ultrasonic probe inserted transcervically into the uterus. Such an ultrasonic probe may be separate from device  6  or may be integrated into device  6 . Alternatively, imaging of the uterus may be performed by MRI imaging. 
     Although one may vary one or more of the speed of rotational movement of inner tubular member  77 , the frequency of oscillating translational movement of inner tubular member  77 , the advance ratio of inner tubular member  77  (i.e., the ratio of the speed at which tubular member  77  oscillates translationally to the speed at which tubular member  77  rotates), and the magnitude of suction provided by vacuum source  392 , particularly good results have been achieved under the following conditions: speed of rotation of tubular member  77 —at least 1100 rpm, more preferably at least 5000 rpm, even more preferably approximately 6000 rpm; frequency of oscillating translational movement of tubular member  77 —at least 1.5 cycles/second, more preferably about 2.5 to 4 cycles/second, even more preferably about 2.8 cycles/second; advance ratio of preferably less than 0.25, more preferably less than 0.15; and vacuum pressures in the range of 200 to 650 mmHg. Preferably, the above parameters are selected to achieve a rate of tissue removal of at least 1.5 gm/min while outer tubular member  76  has an outer diameter of no greater than about 3.0 mm. 
     As can be appreciated, as suction is applied to inner tubular member  77 , some of the distension fluid located in the uterus may incidentally be withdrawn from the uterus through inner tubular member  77 . This loss of distension fluid from the uterus may be undesirable if it interferes with maintenance of the uterus in an adequately distended state. Preferably, system  5  is constructed and operated so that, with a vacuum in excess of 300 mmHg, a volume of no more than about 300 cc/min of fluid is removed. This may involve, for example, applying suction only at specific times, for example, only when the motor for moving inner tubular member  77  is actuated or by closing resection window  89  with inner tubular member  77  each time the motor control is stopped. 
     In general, morcellators may be built in accordance with the present invention to have a lower outside diameter or crossing profile than current commercial products such as the Smith &amp; Nephew Hysteroscopic Morcellator, but at the same time accomplish a higher tissue resection rate. In addition, morcellators in accordance with the present invention may be operated at a significantly higher vacuum while managing total fluid flow within acceptable limits. 
     For example, the cross sectional area of the aspiration lumen in morcellators in accordance with the present invention will typically be no more than about 12.0 square millimeters, and often no more than about 10.0 square millimeters. In certain embodiments, a cross sectional area of the aspiration lumen will be no more than about 8.0 millimeters squared, and, for certain applications, the area will be no more than about 7.5 square millimeters. 
     The tissue resection rate is generally at least about 1.5 gm/min, and often at least about 1.8 gm/min. In certain embodiments, the tissue resection rate is at least about 2.0 gm/min, and, in one embodiment, 2.2 or more gm/min. 
     Morcellators in accordance with the present invention may be constructed to have a fluid usage of no more than about 350 ml/min. In certain embodiments, fluid usage of no more than about 300 ml/min or no more than about 275 ml/min may be constructed. 
     Applied vacuum to the morcellators of the present invention will generally be in the range of from about 200 to about 650 mm Hg. The morcellator will typically be run at a vacuum of at least about 350 mm Hg, and, often at least about 500 mm Hg. 
     In one embodiment of the present invention, the cross sectional area of the aspiration lumen was about 7.1 mm 2 , and yielded a tissue resection rate of about 1.4 gm/min, under vacuum of approximately 600 mm Hg. 
     In general, procedures accomplished in accordance with the present invention will require no more than about 10 minutes, and preferably, no more than about 8 or 9 minutes of active morcellation. During that time, total fluid (e.g. saline) introduced into the uterus will generally be no greater than about 12 liters, and, preferably no greater than about 10 liters or 8 liters. Distension fluid will preferably be maintained at a low enough pressure and short enough time to keep the total saline intravasation below 2.5 liters. 
     In a typical procedure in accordance with the present invention, utilizing a morcellator having an outside diameter of 3 mm, the fluid flow rate for aspiration of saline through the morcellator is approximately 260 ml/min (e.g. within the range of from about 240 to about 280 ml/min). Thus, in a ten minute procedure, approximately 2.6 liters of saline is aspirated through the morcellator. In that same procedure, the tissue resection rate is typically in excess of about 2 gm/min. 
     In a comparative experiment, a device manufactured in accordance with the present invention was compared to the performance of a reciprocating hysteroscopic morcellator from Smith and Nephew. Over a series of experiments with the predicate device, the vacuum was maintained on average in the 200 to 270 mm Hg range, morcellator speed was approximately 1100 rpm, tissue resection rate was approximately 1.4 gm/min, the fluid flow rate through the morcellator was approximately 247 ml/min, and the outside diameter of the morcellator was 4.0 mm. 
     The device constructed in accordance with the present invention was operated at a vacuum of 600 mm Hg, a speed of about 6000 rpm, to produce a resection rate of approximately 2.2 gm/min and an aspiration flow rate of about 266 ml/min through the morcellator. The outside diameter of the device was 3 mm. 
     The morcellator in accordance with the present invention thus produced a significantly higher resection rate, through a smaller outside diameter morcellator, at a roughly comparable flow rate of aspirated saline. In order to increase the resection rate of the predicate device, the vacuum must be significantly increased. For example, when the vacuum pressure in the predicate system was increased to about 670 mm Hg, the tissue cutting improved to 3.5 gm/min but fluid flow rate jumped to 540 ml/min. 
     One challenge with increased fluid flow rate which is responsive to increased vacuum is that the replacement fluid must be infused into the procedure site at an equal rate. In order to infuse fluid at a sufficient rate to allow the predicate device to function at a higher vacuum, the diameter of the already larger predicate morcellator must be increased. Applicants have determined that the use of the morcellator disclosed herein, with an outside diameter of no more than about 3 mm, in combination with the optic system, allows the dilatation of the cervix be limited to no more than about 5.5 mm. Increasing the diameter of the morcellator to accommodate the higher infusion rate as well as the already larger outside diameter of the predicate system is believed to cross the pain threshold and appears to impose the need or desirability for conducting the procedure under a general anesthetic. Applicants believe it to be a significant benefit for many patients to be able to avoid general anesthesia. 
     Referring now to  FIGS. 10( a ) and 10( b ) , there are shown fragmentary longitudinal section views of certain alternate inner tubular members that may be used in tissue removal device  6 . A first such alternate inner tubular member is shown in  FIG. 10( a )  and is represented generally by reference numeral  411 . Inner tubular member  411  may be similar in certain respects to inner tubular member  77 ; however, one notable difference between the two tubular members is that, whereas inner tubular member  77  may be a unitary structure made from a single piece of material, inner tubular member  411  may be formed by joining together two separate pieces of material. More specifically, inner tubular member  411  may comprise a first piece in the form of a proximal stem  413  and a second piece in the form of a distal tip  415 , with distal tip  415  preferably having a length greater than the length of resection window  89  and more preferably having a length of less than about 2 inches and in one construction, about 1 inch. Proximal stem  413  and distal tip  415  may be made of the same material or may be made of different materials. Comparatively hard stainless steel materials, such as 400-series stainless steels (e.g.,  440 C stainless steel) where hardness exceeds Rockwell C values of about 50, are preferred for distal tip  415  as these materials enable a much sharper edge to distal tip  415  to be created. On the other hand, less hard stainless steel materials, such as 300-series stainless steels (e.g., 304 stainless steel), may be preferred for proximal stem  413  as these materials may be comparatively inexpensively formed into long tubular structures, for example, by extrusion whereas harder stainless steel materials must be machined to form tubular structures. The Rockwell C hardness of these proximal tube materials is less than about 40. Proximal stem  413  and distal tip  415  may be joined together by welding or other suitable techniques. Any of a variety of cutter edge and window configurations may be used, depending upon the desired performance, including any of those disclosed in U.S. patent application Ser. No. 12/098,250, filed Apr. 4, 2008 to Gruber, et al., the disclosure of which is hereby incorporated by reference in its entirety herein. 
     Another notable difference between tubular member  411  and tubular member  77  is that, whereas tubular member  77  may have a uniform inner diameter over its length, the inner diameter of distal tip  415  may be reduced as compared to the inner diameter of proximal stem  413  (e.g., 0.082 inch vs. 0.085 inch). Applicants believe that this increase in inner diameter from distal tip  415  to proximal stem  413  may result in a reduction in the incidence of clogging in tubular member  411  as the cut specimen, which has an outer diameter similar to distal tip  415 , moves from distal tip  415  into proximal stem  413 , which has a greater diameter than the cut specimen. This clearance within proximal stem  413  facilitates the proximal movement of the specimen through tubular member  411 . 
     A second alternate inner tubular member is shown in  FIG. 10( b )  and is represented generally by reference numeral  421 . Tubular member  421  may be similar in certain respects to tubular member  411 , the principal difference between the two tubular members being that tubular member  421  may be a unitary structure made from a single piece of material, which may be, for example, a 17-7-series stainless steel. To form tubular member  421  from a tubular structure having a uniform inner diameter, one may first swage or roll the distal end of the tubular structure to reduce the inner diameter of the distal end and then may increase the inner diameter of the remainder of the structure by mechanically honing, expanding, or chemically etching. 
     Referring now to  FIG. 11 , there is shown a side view of an alternate indicator sleeve  431  that may be used in tissue removal device  6 . Indicator sleeve  431  may be similar in most respects to indicator sleeve  98 , the principal difference between the two indicator sleeves being that sleeve  431  may be provided with labeled or unlabeled gradations 433 along its length to indicate the distance between each gradation and a distal end  431 - 1  of sleeve  431 . Because sleeve  431  is preferably dimensioned and positioned so that distal end  431 - 1  of sleeve  431  indicates when distal end  92  of device  6  is aligned with the distal end of introducer  7 , gradations 433 indicate the relative distance between distal end  92  of device  6  and the distal end of introducer  7 . Gradations 433 may comprise, for example, numerical markings, symbols, hash marks, rings, or the like. 
     Referring now to  FIG. 12 , there is shown a fragmentary side view, partly in section, of an alternate combination of a tissue removal device and an introducer that may be used in tissue removal system  5 , the subject tissue removal device being represented generally by reference numeral  441  and the subject introducer being represented generally by reference numeral  443 . 
     Device  441  and introducer  443  may be similar in most respects to device  6  and introducer  7 , respectively, the principal differences being that device  441  may include, instead of sleeve  98 , a position indicator ring  445  fixedly mounted on strain relief member  74 , and introducer  443  may include, instead of proximal portion  203  of body  201 , a proximal portion  447  appropriately shaped to provide just enough interference with bumps  445 - 1  and  445 - 2  on ring  445  so that a user may be given a tactile indication that ring  445  is being inserted into proximal portion  447 . 
     Referring now to  FIGS. 13( a ) and 13( b ) , there are shown fragmentary side views, partly in section, of another alternate combination of a tissue removal device and an introducer that may be used in tissue removal system  5 , the subject tissue removal device being represented generally by reference numeral  451  and the subject introducer being represented generally by reference numeral  453 . 
     Device  451  may be identical to device  441 . Introducer  453  may be similar in most respects to introducer  7 , the principal difference between the two introducers being that introducer  453  may be shaped to include a sound chamber  455  and may additionally include a spring clip or band  457 . Clip  457  may have a fixed end  457 - 1  that is mounted within sound chamber  455  and a free end  457 - 2  that is constructed so as to be deflected by ring  445  when ring  445  is moved distally past clip  457 . The deflection of clip  457  by ring  445  causes clip  457  to oscillate and to generate an audible signal. 
     Referring now to  FIG. 14 , there is shown a fragmentary side view, partly in section, of an alternate tissue removal device that may be used in tissue removal system  5 , said tissue removal device being represented generally by reference numeral  470 . Certain aspects of device  470  not important to an understanding of the invention are neither shown nor described herein. 
     Device  470  may be similar in most respects to device  6 , the principal differences between the two devices being that, whereas device  6  may comprise a rotational mechanism comprising a spur gear  51  engaged with a gear-shaped distal portion  72 - 2  of a shaft  72 , device  470  instead may comprise a rotational mechanism comprising a shaft  472  comprising a tubular elastomeric distal portion  472 - 2  engaged for rotation with an elastomeric O-ring  474  fixedly mounted within a groove  476  of a cylindrical member  478  fixedly coupled to translation drive shaft  35 . 
     Referring now to  FIGS. 15( a ) and 15( b ) , there are shown fragmentary perspective and exploded perspective views, respectively, of another alternate tissue removal device that may be used in tissue removal system  5 , said tissue removal device being represented generally by reference numeral  500 . Certain aspects of device  500  not important to an understanding of the invention are neither shown nor described herein. 
     Device  500  may be similar in many respects to device  6 , one difference between the respective tissue removal devices being that device  500  may comprise a mounting bracket  501 . Bracket  501 , which may be a unitary structure made of a rigid metal or polymer, may be shaped to include a base portion  503 , a proximal block  505  extending upwardly from the proximal end of base portion  503 , a distal block  507  extending upwardly from the distal end of base portion  503 , and an intermediate block  509  extending upwardly from an intermediate portion of base portion  503 . 
     Another difference between device  500  and device  6  is that, whereas device  6  may comprise an internal drive shaft  21 , a translation drive shaft  35 , and a gear assembly  50 , device  500  may instead comprise an internal drive shaft  510 , a translation drive shaft  511 , and a gear assembly  512 . Internal drive shaft  510 , which may be an elongated unitary structure made of a suitably rigid metal or polymer, may be shaped to include a proximal end  513  and a distal end  515 . Proximal end  513  of shaft  510  may be coaxially mounted over and fixed to the distal end of external drive shaft  29 . In this manner, the rotation of shaft  510  may be mechanically coupled to the rotation of shaft  29 . An intermediate portion of shaft  510  may be received within a longitudinal bore  520  provided in block  505  of bracket  501 . Gear assembly  512  may be fixedly mounted on distal end  515  of shaft  510  so as to rotate with shaft  510 . Gear assembly  512  may include a larger diameter proximal spur gear  523  and a smaller diameter distal spur gear  525 . Translation drive shaft  511 , which may be an elongated unitary structure made of a suitably rigid metal or polymer, may be shaped to include a proximal end  537 , an intermediate portion  539 , and a distal end  541 . Proximal end  537  of shaft  511  may be in the shape of a spur gear, which may be engaged with distal gear  525 . In this manner, the rotation of shaft  511  may be mechanically coupled to the rotation of shaft  510 , with the speed of rotation of shaft  511  being dependent on the speed of rotation of shaft  510  and the relative sizes of gear  525  and proximal end  537 . Intermediate portion  539  may extend through a longitudinal bore  509 - 1  provided in block  509  of bracket  501 . Intermediate portion  539  may be shaped to include a double helical portion  540  similar to the double helical portion of shaft  35 . Distal end  541  of shaft  511  may be appropriately dimensioned to be received within an opening  544  provided in block  507  of bracket  501 . It should be noted that, although shaft  511  is adapted for rotation, shaft  511  is translationally stationary. 
     Another difference between device  500  and device  6  is that, whereas device  6  may comprise a shaft  72  mechanically coupled to inner tubular member  77  so as to rotate and to oscillate translationally therewith, device  500  may instead comprise an elongated shaft  551  mechanically coupled to inner tubular member  77  so as to rotate and to oscillate translationally therewith. Shaft  551 , which may be a unitary tubular structure made of a rigid metal or polymer, may be shaped to include a spur gear engaged with proximal gear  523 . The gear may be elongated so that it may maintain engagement with proximal gear  523  even as the gear moves translationally relative to proximal gear  523 . The speed at which shaft  551  rotates may be the same as or different than the speed at which gear  523  rotates, depending, for example, on the relative diameters of the two gears (the ratio of the rotational speeds of the two gears being inversely proportional to the ratio of the diameters of the two gears). Consequently, by appropriately dimensioning the gears, one can achieve a desired rotational speed, even where the rotational speed of the external drive shaft is fixed. For example, in the embodiment shown, the gear of shaft  551  may have a diameter that is one-third the diameter of gear  523  and, therefore, rotates three times as fast as gear  523 . At the same time, proximal end  537  of shaft  511  may have a diameter that is four-thirds the diameter of gear  525  and, therefore, rotates three-quarters as fast as gear  525 . Therefore, if the external drive shaft has a speed of rotation of about 2000 rpm, shaft  551  (and inner tubular member  77 ) would rotate at about 6000 rpm and shaft  511  would rotate at about 1500 rpm, which, with an appropriate shaping of the double helix portion of shaft  511 , could be used to achieve an oscillating translational speed for inner tubular member  77  of about 2.8 cycles/second. 
     Referring now to  FIG. 16 , there is shown a fragmentary side view of an alternate tissue removal device that may be used in tissue removal system  5 , said tissue removal device being represented generally by reference numeral  570 . Certain aspects of device  570  not important to an understanding of the invention are neither shown nor described herein. 
     Device  570  may be similar in many respects to device  6 . One difference between the two devices may be that, whereas device  6  may fix inner drive shaft  21  to external drive shaft  29  for rotation therewith and may couple the rotation of inner tubular member  77  to inner drive shaft  21  through the engagement of shaft  72  and gear  51 , device  570  may instead fix inner tubular member  77  to external drive shaft  29  for rotation therewith and may couple the rotation of inner drive shaft  21  to inner tubular member  77  through the engagement of a pair of spur gears  572  and  574 . Gear  572  may be coaxially inserted over and fixed to inner tubular member  77 , and gear  574  may be coaxially inserted over and fixed to inner drive shaft  21 . Gears  572  and  574  may be sized to be, for example, in a 1:4 ratio, respectively, so that, if external drive shaft  29  rotates at about 6000 rpm, inner tubular member  77  also rotates at about 6000 rpm whereas inner drive shaft  21  rotates at about 1500 rpm. 
     Referring now to  FIG. 17 , there is shown a fragmentary side view of an alternate tissue removal device that may be used in tissue removal system  5 , said tissue removal device being represented generally by reference numeral  580 . Certain aspects of device  580  not important to an understanding of the invention are neither shown nor described herein. 
     Device  580  may be similar in many respects to device  6 . One difference between the two devices may be that, whereas device  6  may fix inner drive shaft  21  to external drive shaft  29  for rotation therewith and may couple the rotation of inner tubular member  77  to inner drive shaft  21  through the engagement of shaft  72  and gear  51 , device  580  instead may couple the rotation of inner drive shaft  21  to external drive shaft  29  through the engagement of a pair of spur gears  582  and  584  and may couple the rotation of inner tubular member  77  to external drive shaft  29  through the engagement of a spur gear  586  with gear  582 . Gear  582  may be coaxially inserted over and fixed to external drive shaft  29 , gear  584  may be coaxially inserted over and fixed to inner drive shaft  21 , and gear  586  may be coaxially inserted over and fixed to inner tubular member  77 . Gears  582  and  584  may be sized to be, for example, in a 1:2 ratio, respectively, and gears  582  and  586  may be sized to be, for example, in a 2:1 ratio, respectively. In this manner, if external drive shaft  29  rotates at about 3000 rpm, inner tubular member  77  rotates at about 6000 rpm and inner drive shaft  21  rotates at about 1500 rpm. 
     Referring now to  FIG. 18 , there is shown a fragmentary perspective view of an alternate tissue removal device that may be used in tissue removal system  5 , said tissue removal device being represented generally by reference numeral  600 . Certain aspects of device  600  not important to an understanding of the invention are neither shown nor described herein. 
     Device  600  may be similar in many respects to device  6 . One difference between the two devices may be their respective mechanisms for rotating and translationally reciprocating inner tubular member  77 . More specifically, device  600  may comprise an internal drive shaft  603  fixed to an external drive shaft (not shown) so as to rotate therewith. Internal drive shaft  603  may comprise a proximal portion  605  and a distal portion  607 . A spur gear  609  and a bevel gear  611  may be coaxially mounted over distal portion  607  and fixed thereto for rotation therewith, with bevel gear  611  being positioned distally relative to spur gear  609 . A spur gear  613  may be coaxially mounted over inner tubular member  77  and fixed thereto for rotation therewith, gear  613  being engaged with gear  609  so that the rotation of internal drive shaft  603  causes the rotation of inner tubular member  77 . (The speed of rotation of inner tubular member  77 , as compared to that of drive shaft  603 , may be controlled by the relative diameters of gears  609  and  613 ). A bevel gear  615 , positioned distally relative to internal drive shaft  603 , may be engaged with bevel gear  611 . A saddle  619  may be coaxially mounted over inner tubular member  77 , saddle  619  being fixed to inner tubular member  77  for translational movement therewith but permitting tubular member  77  to freely rotate therewithin. Saddle  619  and bevel gear  615  may be coupled to one another by a pin (not shown) extending upwardly from the top surface  621  of gear  615  and a slot (not shown) provided on the bottom surface of saddle  619 , the slot in saddle  619  receiving the pin on bevel gear  615 . The slot in saddle  619  may be oriented perpendicularly to the longitudinal axis of inner tubular member  77  and may be appropriately dimensioned so that the pin on bevel gear  615  travels back and forth within the slot in saddle  619  as bevel gear  615  rotates. In this manner, the rotation of bevel gear  615  may cause the translational oscillation of inner tubular member  77 . 
     Referring now to  FIG. 19 , there is shown a fragmentary perspective view of an alternate tissue removal device that may be used in tissue removal system  5 , said tissue removal device being represented generally by reference numeral  700 . Certain aspects of device  700  not important to an understanding of the invention are neither shown nor described herein. 
     Device  700  may be similar in many respects to device  6 . One difference between the two devices may be their respective mechanisms for rotating and translationally reciprocating inner tubular member  77 . More specifically, device  700  may comprise an internal drive shaft  703  fixed to an external drive shaft (not shown) so as to rotate therewith. A spur gear  705  and a translation cam  707  may be coaxially mounted over drive shaft  703  and fixed thereto for rotation therewith, with translation cam  707  being positioned distally relative to spur gear  705 . A spur gear  711  may be coaxially mounted over inner tubular member  77  and fixed thereto for rotation therewith, gear  711  being engaged with gear  705  so that the rotation of internal drive shaft  703  causes the rotation of inner tubular member  77 . (The speed of rotation of inner tubular member  77 , as compared to that of drive shaft  703 , may be controlled by the relative diameters of gears  705  and  711 ). A saddle  713  may be coaxially mounted over inner tubular member  77 , saddle  713  being fixed to inner tubular member  77  for translational movement therewith but permitting tubular member  77  to freely rotate therewithin. Saddle  713  and translation cam  707  may be coupled to one another by a pin (not shown) extending downwardly from saddle  713  and a looped groove  717  provided in cam  707 , groove  717  receiving the pin on saddle  713 . Groove  717  in cam  707  may be shaped to extend from about the proximal end  707 - 1  of cam  707  to about the distal end  707 - 2  of cam  707  and back to about the proximal end  707 - 1  of cam  707  over the course of one rotation of cam  707 . In this manner, as cam  707  rotates and the pin travels back and forth within groove  717 , inner tubular member  77  may be translationally oscillated correspondingly. 
     Referring now to  FIG. 20 , there is shown a fragmentary perspective view of an alternate tissue removal device that may be used in tissue removal system  5 , said tissue removal device being represented generally by reference numeral  800 . Certain aspects of device  800  not important to an understanding of the invention are neither shown nor described herein. 
     Device  800  may be similar in many respects to device  6 . One difference between the two devices may be their respective mechanisms for rotating and translationally reciprocating inner tubular member  77 . More specifically, device  800  may comprise an internal drive shaft  801  fixed to an external drive shaft (not shown) so as to rotate therewith. A spur gear  803  may be coaxially mounted over drive shaft  801  and fixed thereto for rotation therewith. In addition, a translation cam  805  may be coaxially mounted over drive shaft  801  and fixed thereto for rotation therewith. Translation cam  805  may comprise a tubular portion  805 - 1  and a disc portion  805 - 2 , disc portion  805 - 2  being fixedly mounted on tubular portion  805 - 1  at a non-perpendicular angle relative to the longitudinal axis of tubular portion  805 - 2 . A spur gear  813  may be coaxially mounted over inner tubular member  77  and fixed thereto for rotation therewith, gear  813  being engaged with gear  803  so that the rotation of internal drive shaft  801  causes the rotation of inner tubular member  77 . (The speed of rotation of inner tubular member  77 , as compared to that of drive shaft  801 , may be controlled by the relative diameters of gears  803  and  813 ). A saddle  819  may be coaxially mounted over inner tubular member  77 , saddle  819  being fixed to inner tubular member  77  for translational movement therewith but permitting tubular member  77  to freely rotate therewithin. Saddle  819  may be shaped to include a recess  821 , which may receive the top of disc portion  805 - 2 . In this manner, as drive shaft  801  rotates, causing disc portion  805 - 2  to “wobble” back and forth, saddle  819 , and thus inner tubular member  77 , may be translationally oscillated correspondingly. 
     Referring now to  FIG. 21 , there is shown a fragmentary perspective view of an alternate tissue removal device that may be used in tissue removal system  5 , said tissue removal device being represented generally by reference numeral  900 . Certain aspects of device  900  not important to an understanding of the invention are neither shown nor described herein. 
     Device  900  may be similar in many respects to device  6 . One difference between the two devices may be their respective mechanisms for rotating and translationally reciprocating inner tubular member  77 . More specifically, device  900  may comprise an internal drive shaft  901  fixed to an external drive shaft (not shown) so as to rotate therewith. A spur gear  903  and a worm gear  905  may be coaxially mounted over drive shaft  901  and fixed thereto for rotation therewith. A spur gear  907  may be coaxially mounted over inner tubular member  77  and fixed thereto for rotation therewith, gear  907  being engaged with gear  903  so that the rotation of internal drive shaft  901  causes the rotation of inner tubular member  77 . (The speed of rotation of inner tubular member  77 , as compared to that of drive shaft  901 , may be controlled by the relative diameters of gears  903  and  907 ). A worm gear  911  may be engaged with worm gear  905  so that worm gear  911  rotates as worm gear  905  rotates. A pin  913  may be mounted near the periphery of a front face  911 - 1  of worm gear  911 . A reciprocation arm  915  may have a first end secured to pin  913  and a second end secured to a block  917  translationally coupled to inner tubular member  77 . In this manner, as worm gear  911  rotates and the position of pin  913  on worm gear  911  changes, arm  915  moves block  917  and inner tubular member  77  back and forth translationally. 
     As can be appreciated, one would like to minimize the amount of distension fluid that flows from the uterus of the patient through the tissue removal device when the tissue removal device is left in the patient but the cutting motor for the tissue removal device has temporarily been turned off, e.g., during those periods when the operator of the tissue removal device stops cutting to examine the patient. Such a loss of distension fluid is undesirable for at least the reason that the lost distension fluid will need to be replenished in order to keep the uterus distended. In device  6 , this problem may be addressed through electronics by sensing when the motor for device  6  is about to be turned off and, in those instances, by positioning inner tubular member  77  translationally relative to outer tubular member  76  so that resection window  89  is closed. An alternate approach to this problem is exemplified by tissue removal device  940 , which is shown in  FIGS. 22( a ) through 22( e ) . Certain aspects of device  940  not important to an understanding of the invention are neither shown nor described herein. 
     Device  940  is similar in certain respects to device  6 . However, one difference between the respective devices is that device  940  may comprise an inner tubular member  943  having a closed proximal end  945  and a side window  947 . A spring mount  949  may be coaxially mounted over inner tubular member  943  and fixed thereto for rotation therewith. The proximal end of a spring  951  may be fixed to spring mount  949 , and the distal end of spring  951  may be fixed to a valve member  953  coaxially mounted over inner tubular member  943 , valve member  953  being capable of rotating relative to inner tubular member  943 . Valve member  953  may include a side window  955 . Side window  955  may be alignable with side window  943  depending on the respective rotational positions of inner tubular member  943  and valve member  953 . A stop  957  may be formed on inner tubular member  943 , stop  957  being detachably engageable with valve member  953  to couple the rotation of valve member  953  with inner tubular member  943 . A vacuum housing  959  may be coaxially mounted over valve member  953 , valve member  953  being freely rotatable within vacuum housing  959 . Outer tubular member  76  may be fixedly mounted on vacuum housing  959 . A pair of O-rings  961 - 1  and  961 - 2  may be provided to function as seals. 
     Prior to the cutting motor of device  940  being actuated, side window  955  of valve member  953  and side window  947  of inner tubular member  943  are 90 degrees out of register with one another. However, once the cutting motor of device  940  is actuated, inner tubular member  943  begins to rotate. This causes spring  951  to try to unwind, thereby causing valve member  953  to rotate so that side window  955  of valve member  953  is aligned with side window  947  of inner tubular member  943 . With valve member  953  thus rotationally aligned with inner tubular member  943 , stop  957  prevents further rotation of valve member  953  relative to inner tubular member  943 . When the cutting motor of device  940  is then turned off, spring  951  causes valve member  953  to be rotated back to its original orientation relative to inner tubular member  943 . 
     As noted above, introducer  7  preferably comprises valve  233 , which is designed to keep fluid from escaping from the patient when device  6  is not inserted into introducer  7 . However, there may be situations in which it is desirable to simultaneously have fluid flowing into and out of the patient without having device  6  inserted into introducer  7 . Therefore, referring now to  FIG. 23 , there is shown a fragmentary section view of an obturator  965  positioned within a channel of introducer  7 . Obturator  965  may be shaped to include a blunt distal end  967  and a plurality of openings  969  leading to a longitudinally-extending channel  971 . Obturator  965  may be positioned in instrument channel  196 , as shown, or may be positioned in fluid input channel  198 - 1  or fluid input channel  198 - 2  to provide bidirectional fluid flow (for example, with fluid inflow exiting channels  198 - 1  or  198 - 2  in the space between channels  198 - 1  or  198 - 2  and obturator  965  and with fluid outflow entering obturator  965  through openings  969 ). The fluid outflow entering channel  971  through openings  969  may exit obturator  965  through the proximal end (not shown) of obturator  965 . 
     An alternate obturator  972  is shown in  FIG. 24 , obturator  972  having a side opening  973  at an intermediate location along its length, side opening  973  being aligned with an outflow fluid channel  975  provided in an alternate introducer  977 . If desired, obturator  972  may be made of a resilient member having a bend and introducer  977  may be provided with a sheath  978  made of a flexible material. In this manner, obturator  972  may be used to provide a bend to sheath  978 , which, by rotating the proximal end  979  of obturator  972 , may be used to steer the distal end of sheath  978 . 
     Referring now to  FIGS. 25( a ) and 25( b ) , there is shown an alternate combination of an obturator and an introducer according to the present invention, the obturator being represented generally by reference numeral  980  and the introducer being represented generally by reference numeral  981 . 
     Obturator  980 , which may be similar in many respects to obturator  965 , may comprise a distal member  982  and a proximal member  983 . Distal member  982  may be tubular and may comprise an open distal end  984 , a closed proximal end  985 , and a side opening  986 , with proximal member  983  being mounted over proximal end  985  of distal member  982 . 
     Introducer  981  may be similar in many respects to introducer  7 , one difference between the respective introducers being that introducer  981  may additionally comprise a fluid outflow channel  987 . Channel  987  may comprise a distal end  987 - 1  that may be aligned with side opening  986  of obturator  980  when obturator  980  is installed in introducer  981 . In this manner, outflow fluid may flow from obturator  980  to channel  987  and may exit introducer  981  through a proximal end  987 - 2  of channel  987 . Introducer  981  may additionally comprise a valve  988 - 1  and a valve  989 - 2 . Valve  988 - 1 , which may be a stopcock valve, may be used to control the flow of fluid through channel  987 . Valve  988 - 2 , which may be a stopcock valve, may be used to control the flow of fluid through inflow channel  989 . 
     Referring now to  FIGS. 26( a ) through 26( c ) , there are shown various views of an alternate introducer device to introducer device  7 , the alternate introducer device being represented generally by reference numeral  990 . 
     Introducer device  990  may be similar in many respects to introducer device  7 . One difference between introducer device  990  and introducer device  7  may be that, whereas introducer device  7  may comprise a sheath  191  having a top lumen  196 , a bottom lumen  197  and a pair of side lumens  198 - 1  and  198 - 2 , introducer device  990  may comprise a top tubular member  991 , a bottom tubular member  992 , a sleeve  993 , and a distal cap  994 . Top tubular member  991  may be used, for example, as an instrument channel to receive, for example, tissue removal device  6  or obturator  965 . Bottom tubular member  992  may be used, as is shown, for example, to receive distal end  319  of hysteroscope  8 . Sleeve  993 , which may be made of stainless steel or the like, may be appropriately dimensioned to coaxially receive top tubular member  991  and bottom tubular member  992  and may be shaped to define a pair of fluid channels  995  on opposite sides of tubular members  991  and  992  in the spaces between the inner surface of sleeve  993  and the outer surfaces of tubular members  991  and  992 . A plurality of transverse openings  996  may be provided in sleeve  993  near the distal end  997  thereof, openings  996  providing side access to fluid channels  995 . In this manner, fluid inflow to the patient may be provided by having the fluid pass distally through channels  995  and then exit radially through openings  996 . Fluid outflow from the patient may travel proximally through cap  994  and then proximally through top tubular member  991  (for example, by passing through an instrument positioned in top tubular member  991 ). It is believed that the fluid flow pattern provided by introducer device  990  may be particularly effective in removing blood and other undesired fluids from a patient. Cap  994  may include a retainer  998 , which may receive the distal ends of tubular members  991  and  992  and which may be inserted into and fixed to the distal end  997  of sleeve  993 . 
     Referring now to  FIG. 27 , there is shown a partially exploded perspective view of a second embodiment of a tissue removal system, the tissue removal system being constructed according to the teachings of the present invention and being represented generally by reference numeral  1007 . 
     System  1007  may comprise a tissue removal device  1008 , a vacuum assembly  1009 , and a motor drive assembly  1010 . Although not shown in the present embodiment, system  1007  may also include an introducer device, a flexible hysteroscope, and a fluid supply similar to those of system  5  described above. 
     Tissue removal device  1008  may comprise a morcellator assembly  1013  and a drive assembly  1015 , morcellator assembly  1013  being removably mounted on drive assembly  1015  in the manner described further below. 
     Referring now to  FIGS. 28( a ) through 28( d ) , morcellator assembly  1013  may be seen in greater detail. Morcellator assembly  1013  may comprise a housing  1021 . Housing  1021 , which may be an elongated unitary structure made of a rigid polymer or metal, may be a generally tubular member shaped to include a proximal end  1023 , a distal end  1025 , and a side wall  1027 . Side wall  1027  may be generally cylindrical, with a portion  1028  of its bottom surface being beveled. A longitudinal lumen  1029  may extend from proximal end  1023  to distal end  1025 . An intermediate portion  1031  of lumen  1029  may be expanded in diameter and may be accessible through an opening  1033  in side wall  1027 . A proximal portion  1035  of lumen  1029  extending distally from proximal end  1023  to a point spaced proximally from intermediate portion  1031  may be expanded in diameter and may be internally threaded. 
     Morcellator assembly  1013  may additionally comprise a pair of tubular bushings  1041  and  1043 . Bushing  1041 , which may be a unitary structure made of a rigid polymer or metal, may be seated within intermediate portion  1031  of lumen  1029 , near its proximal end, and may be fixedly secured to housing  1021  with screws  1042 . Bushing  1043 , which may be a unitary structure made of a rigid polymer or metal, may be seated within intermediate portion  1031  of lumen  1029 , near its distal end, and may be fixedly secured to housing  1021  with screws  1044 . Bushing  1041  may be shaped to include a bore  1045 , and bushing  1043  may be shaped to include a bore  1047 , bores  1045  and  1047  being coaxially aligned with lumen  1029  of housing  1021 . 
     Morcellator assembly  1013  may further comprise an elongated shaft  1051 . Shaft  1051 , which may be a unitary structure made of brass or another suitable rigid metal or polymer, may be shaped to include a proximal portion  1053 , a distal portion  1055 , an intermediate portion  1057 , and a longitudinal bore  1059 . Proximal portion  1053  of shaft  1051  may be slidably mounted in bore  1045  of bushing  1041  and may be sized to freely rotate therewithin. Distal portion  1055  of shaft  1051  may be slidably mounted in bore  1047  of bushing  1043  and may be sized to freely rotate therewithin. Intermediate portion  1057  of shaft  1051  may be positioned between bushings  1041  and  1043  and may be in the shape of a gear having an enlarged external diameter relative to proximal portion  1053  and distal portion  1055 . 
     Morcellator assembly  1013  may further comprise a translational coupling block  1061 . Block  1061 , which may be a unitary structure made of a rigid polymer or metal, may be a tubular member shaped to include a proximal end  1063 , a distal end  1064 , a side wall  1065 , and a longitudinal bore  1066 . Block  1061  may be coaxially mounted over proximal portion  1053  of shaft  1051 , with bore  1066  being sized relative to proximal portion  1053  so that proximal portion  1053  may freely rotate within bore  1066 . Side wall  1065  of block  1061  may be shaped to correspond generally to the shape of intermediate portion  1031  of lumen  1029 . In this manner, block  1061  may be kept rotationally stationary within housing  1021 . Block  1061  may be translationally fixed relative to shaft  1051  with a retaining ring  1067  inserted coaxially over proximal portion  1053  and secured to proximal portion  1053  with a set screw  1068 . A washer  1069  may be inserted coaxially over proximal end  1053  of shaft  1051  between distal end  1063  of block  1061  and intermediate portion  1057  of shaft  1051  to prevent any wear caused by contact between intermediate portion  1057  against distal end  1063  of block  1061  as intermediate portion  1057  rotates. Side wall  1065  of block  1061  may further be shaped to include a waist  1070  of reduced external diameter. In this manner, with block  1061  coaxially mounted over proximal portion  1053  of shaft  1051 , a pair of slots  1071 - 1  and  1071 - 2  may be formed between block  1061  and housing  1021 . 
     Morcellator assembly  1013  may further comprise a strain relief member  1072 . Strain relief member  1072 , which may be a unitary structure made of a rigid polymer or metal, may be a tubular member shaped to include a proximal portion  1073  and a distal portion  1074 . Proximal portion  1073  may be slightly greater in diameter than distal portion  1074  and may include a bifurcating slot  1075 . Proximal portion  1073  of strain relief member  1072  may be disposed within the distal portion of lumen  1029 , with distal portion  1074  of strain relief member  1072  extending distally from distal end  1025  of housing  1021  for a short distance, such as, for example, approximately 2 inches. 
     Morcellator assembly  1013  may further comprise a cutting mechanism. In the present embodiment, the cutting mechanism may comprise an outer tubular member  1076  and an inner tubular member  1077 , inner tubular member  1077  moving rotationally and, at the same time, oscillating translationally relative to outer tubular member  1076  in the manner to be described further below. Outer tubular member  1076 , which may be a unitary structure made of stainless steel or another similarly suitable material, may be shaped to include an open proximal end  1079 , a closed distal end  1081 , and a lumen  1083  extending from open proximal end  1079  to a point just prior to closed distal end  1081 . Member  1076  may be coaxially mounted within strain relief member  1072 , with proximal end  1079  of member  1076  disposed within proximal portion  1073  of strain relief member  1072  and with distal end  1081  of member  1076  extending distally beyond distal portion  1074  of strain relief member  1072  for an extended distance, such as, for example, five inches. The combination of proximal end  1079  of member  1076  and proximal portion  1073  of strain relief member  1072  may be securely retained in housing  1021  using a screw  1085  inserted through an opening  1087  in housing  1021 , screw  1085  pressing proximal portion  1073  of strain relief member  1072  tightly against proximal end  1079  of member  1076 . 
     Outer tubular member  1076  may be further shaped to include a resection window  1089  into which tissue may be captured and drawn, window  1089  being located proximate to distal end  1081 , such as, for example, 0.25 inch from distal end  1081 . Window  1089  may be shaped to include a proximal end  1089 - 1  and a distal end  1089 - 2 . Proximal end  1089 - 1  may slope gradually proximally, and distal end  1089 - 2  may slope gradually distally. More specifically, window  1089  may have a length of approximately 0.55 inch, proximal end  1089 - 1  may be a radial end having a radius of curvature of, for example, 0.085 inch, and distal end  1089 - 2  may be a radial end having a radius of curvature of, for example, 0.150 inch. Window  1089  may extend over a substantial portion of the circumference of tubular member  1076 , such as, for example, about 60% of the circumference. 
     Outer tubular member  1076  may have an outer diameter less than about 5.5 mm. However, in order to reduce the risk of injury to the patient and in order to obviate the need for anesthesia to be administered to the patient, outer tubular member  1076  preferably has an outer diameter less than about 5 mm, more preferably less than 4 mm, even more preferably less than 3 mm, and still even more preferably less than 2 mm. 
     Inner tubular member  1077 , which may be an elongated unitary structure made of stainless steel or another similarly suitable material, may be shaped to include a proximal end  1091 , a distal end  1092 , and a longitudinal lumen  1093 . Distal end  1092  may be shaped to include an external bevel, such as, for example, an external bevel of approximately 20 degrees. An intermediate portion of tubular member  1077  may be received within bore  1059  of shaft  1051  and may be fixedly coupled to shaft  1051  for translational and rotational movement therewith using a retaining ring  1094 - 1 , a slotted sleeve  1094 - 2  and a pair of set screws  1095 . The proximal portion of ring  1094 - 1  may be screwed onto the distal end of shaft  1051 , with the distal portion of ring  1094 - 1  extending over member  1077 . Sleeve  1094 - 2  may be inserted coaxially between member  1077  and ring  1094 - 1 , and set screws  1095  may be inserted through a transverse opening  1096  in retaining ring  1094 - 1  to couple ring  1094 - 1  and sleeve  1094 - 2  to member  1077 . Tubular member  1077  may have a suitable length so that, when tubular member  1077  is in a fully retracted (i.e., proximal) position, proximal end  1091  of tubular member  1077  may extend proximally a short distance from proximal end  1023  of housing  1021  and distal end  1092  of tubular member  1077  may be withdrawn sufficiently to permit tissue to enter window  1089 . At the same time, tubular member  1077  may have a length so that, when tubular member  1077  is in a fully advanced (i.e., distal) position, distal end  1092  of tubular member  1077  may be positioned distally of distal end  1089 - 2  of window  1089 . 
     Morcellator assembly  1013  may further comprise a fitting  1097 . Fitting  1097 , which may be a unitary structure made of a rigid polymer or metal, may be a tubular member shaped to include a proximal portion  1098 , a distal portion  1099  and a longitudinal lumen  1100 . Proximal portion  1098 , which may be barbed, may be coupled through a length of tubing to vacuum assembly  1009 . Distal portion  1099  of fitting  1097  may be externally threaded for mating engagement with proximal portion  1035  of housing  1021 . Lumen  1100  of fitting  1097  may be dimensioned to slidably receive proximal end  1091  of tubular member  1077 . An O-ring  1101  may be disposed within lumen  1100  to provide a seal around tubular member  1077 . 
     Referring now to  FIGS. 29( a ) and 29( b ) , drive assembly  1015  may be seen in greater detail. Drive assembly  1015  may include a main body  1105 . Main body  1105 , which may be a unitary structure made of a rigid polymer or metal, may be a generally trough-shaped member shaped to include a distal end  1107 , a proximal end  1109 , and a side wall  1111 . Distal end  1107  may be generally circular and may include a distal surface that includes a central portion  1115  and a peripheral portion  1117 . Central portion  1115  may be recessed relative to peripheral portion  1117 . A central transverse opening  1119  may be provided in central portion  1115 , and a pair of smaller transverse openings  1120  may be provided in central portion  1115  on opposite sides of central opening  1119 . Proximal end  1109  may be generally circular and may include a proximal surface that includes a central portion  1123  and a peripheral portion  1125 . Central portion  1123  may be recessed relative to peripheral portion  1125 . A central transverse opening  1127  may be provided in central portion  1123 , and a pair of smaller transverse openings  1129  may be provided in central portion  1123  on opposite sides of central opening  1127 . Side wall  1111  may extend from distal end  1107  to proximal end  1109  but only over about the top half of their respective circumferences. A longitudinal groove  1131  may be provided along the outer surface of side wall  1111  to receive a corresponding portion of housing  1021  of morcellator assembly  1013 . Groove  1131  may include a first transverse slot  1133  extending though side wall  1111  and a second transverse slot  1135  extending through side wall  1111 . First transverse slot  1133  may be spaced a short distance from distal end  1107  and may be oriented generally circumferentially relative to side wall  1111 . Second transverse slot  1135  may be spaced a short distance from proximal end  1109  and from first transverse slot  1133  and may be oriented generally longitudinally relative to side wall  1111 . The inner surface of side wall  1111  may additionally be shaped to include a block  1141  located between first transverse slot  1133  and second transverse slot  1135 . Block  1141  may be shaped to include an exterior groove  1143  on its bottom surface, groove  1143  extending parallel to second transverse slot  1135 . A bracket  1145 , which may be a unitary structure made of a rigid polymer or metal, may be secured to the bottom surface of block  1141  with a pair of screws  1146 . Bracket  1145  may be shaped to include a groove  1147  on its top surface that is complementarily shaped to groove  1143 , with grooves  1143  and  1147  jointly defining a channel of generally cylindrical shape. 
     Drive assembly  1015  may additionally comprise a mechanism for driving rotational movement of inner tubular member  1077 . Such a mechanism may comprise a first motor  1151 . Motor  1151 , in turn, may comprise a first end  1152  having a shaft  1153  extending therefrom. First end  1152  may be received within central portion  1115  of distal end  1107  of body  1105  and may be secured thereto with screws  1156  inserted through openings  1120  and into complementary openings  1157  in first end  1152  of motor  1151 . With motor  1151  thus secured to distal end  1107 , shaft  1153  may extend through central transverse opening  1119  and may freely rotate therewithin. Cables  1159  may be used to connect motor  1151  to control unit  1010 . 
     In addition, the aforementioned mechanism for driving rotational movement of inner tubular member  1077  may further comprise a coupling block  1161  and a gear  1162 . Coupling block  1161 , which may be a unitary structure made of a rigid polymer or metal, may be shaped to include a distal base  1163  and a proximal post, the proximal post extending proximally from base  1163 . Base  1163  may be shaped to include a cavity  1164  accessible from its distal end into which shaft  1153  of motor  1151  may be received and secured with a screw  1165 , thereby mechanically coupling shaft  1153  to block  1161 . The proximal post may be shaped to include a distal portion  1166  of increased diameter and a proximal portion  1167  of decreased diameter. Gear  1162 , which may be a unitary member made of a rigid polymer or metal, may be shaped to include a distal tube  1168  and a proximal toothed wheel  1169 . Tube  1168  may be coaxially mounted on portion  1166  of block  1161  and mechanically coupled thereto with a screw  1170 . Wheel  1169  may be positioned so that a portion of wheel  1169  extends through slot  1133  for engagement with intermediate portion  1057  of shaft  1051 . In this manner, rotation of wheel  1169  causes the rotation of shaft  1051 . Proximal portion  1167  of post  1165 , which may extend proximally a short distance beyond wheel  1169 , may be seated within a bearing  1173 , bearing  1173  being seated within the distal end of the channel jointly defined by block  1141  and bracket  1145 . 
     Drive assembly  1015  may further comprise a mechanism for driving oscillating translational movement of inner tubular member  1077 . Such a mechanism may comprise a second motor  1181 . Motor  1181 , in turn, may comprise a first end  1182  having a shaft  1183  extending therefrom. First end  1182  may be received within central portion  1123  of proximal end  1109  of body  1105  and may be secured thereto with screws  1186  inserted through openings  1129  and into complementary openings  1187  in first end  1182  of motor  1181 . With motor  1181  thus secured to proximal end  1109 , shaft  1183  may extend through central transverse opening  1127  and may freely rotate therewithin. A cable  1189  may be used to connect motor  1181  to control unit  1010 . 
     In addition, the aforementioned mechanism for driving oscillating translational movement of inner tubular member  1077  may further comprise a coupling block  1191 , a threaded bolt  1192 , and a carriage  1193 . Coupling block  1191 , which may be a unitary structure made of a rigid polymer or metal, may be shaped to include a proximal opening  1194  and a distal opening  1195 . Proximal opening  1194  may be dimensioned to securely receive shaft  1183  of motor  1181 , thereby mechanically coupling shaft  1183  to block  1191 . Distal opening  1195  may be dimensioned to securely receive the proximal end of threaded bolt  1192 , thereby mechanically coupling bolt  1192  to block  1191 . The distal end of bolt  1192  may be seated within a bearing  1196 , which, in turn, may be seated within the proximal end of the channel jointly defined by block  1141  and bracket  1145 . Carriage  1193 , which may be a unitary structure made of a rigid polymer or metal, may be shaped to include a bore  1197  and a pair of upwardly extending tines  1198 . A rigid collar  1199  may be fixedly mounted within bore  1197  of carriage  1193  using a pair of screws  1200 . Collar  1199  may be internally threaded to engage bolt  1192 . In this manner, as bolt  1192  rotates, carriage  1193  moves translationally along the longitudinal axis of bolt  1192 , with proximal or distal translational movement of carriage  1193  effected by the clockwise or counterclockwise rotation, respectively, of bolt  1192 . Carriage  1193  may be mechanically coupled for translational movement to shaft  1051  by tines  1198 , with tines  1198  extending through slot  1135  of body  1105  and being received within slots  1071 - 1  and  1071 - 2  of morcellator assembly  1013 . 
     As can be appreciated from the above description, the speed at which inner tubular member  1077  rotates and the speed at which inner tubular member  1077  oscillates translationally are separately and independently controlled, with the rotation of inner tubular member  1077  being controlled by motor  1151  and with the oscillating translation of inner tubular member  1077  being controlled by motor  1181 . 
     Drive assembly  1015  may further comprise a body  1201 . Body  1201 , which may be a unitary structure made of a rigid polymer or metal, may be shaped to include a distal end  1203 , a proximal end  1205 , a side wall  1207 , and a cavity  1208 . Distal end  1203  may be generally semi-circular in shape, and proximal end  1205  may be generally semi-annular in shape. Side wall  1207  may be semi-annular in transverse cross-section and may extend from distal end  1203  to proximal end  1205 . A longitudinal groove  1209 , similar in shape to groove  1131  of body  1105 , may be provided along the top, outer surface of side wall  1207  to receive a corresponding portion of housing  1021  of morcellator assembly  1013 . Cavity  1208  may be dimensioned to receive motor  1151 . A pair of longitudinal lumens  1213  may be provided in body  1201 , lumens  1213  extending through distal end  1203 , proximal end  1205 , and side wall  1207 . Lumens  1213  may be aligned with corresponding threaded cavities  1215  in body  1105  so that proximal end  1205  of body  1201  and may be fixed to distal end  1107  of body  1105  using screws  1217  inserted through body  1201  and into cavities  1215 . 
     Drive assembly  1015  may further comprise a locking clip  1221 . Locking clip  1221 , which may be a unitary structure made of a rigid polymer or metal, may be shaped to include a base  1223 , a pair of parallel legs  1225 , and a pair of parallel feet  1227 . Legs  1225  may extend upwardly from base  1223 , with legs  1225  being spaced inwardly a short distance from the ends of base  1223 . Feet  1227  may extend transversely from legs  1225 . Base  1223  may be received within a matingly-shaped recess  1229  provided on body  1105  and may be securely retained within recess  1229  by securing body  1201  to body  1105 . With clip  1221  thus mounted on body  1105 , legs  1225  extend upwardly beyond body  1105  and may be inserted into corresponding L-shaped slots  1230  in housing  1021  of morcellator assembly  1013 . In this manner, clip  1221  may be used to reversibly and lockably couple drive assembly  1015  to morcellator assembly  1013 . More specifically, to lockably couple drive assembly  1015  to morcellator assembly  1013 , one may insert feet  1227  into the proximal portions  1230 - 1  of slots  1230  and may then slide feet  1227  distally to the distal portions  1230 - 2  of slots  1230 . To uncouple drive assembly  1015  from morcellator  1013 , feet  1227  may be slid proximally from distal portions  1230 - 2  to proximal portions  1230 - 1  and may then be removed from slots  1230 . 
     Drive assembly  1015  may further comprise a body  1231 . Body  1231 , which may be a unitary structure made of a rigid polymer or metal, may be a generally cylindrical member shaped to include a proximal end  1233 , a distal end  1235 , and a side wall  1237 . A cavity  1239  may extend proximally from distal end  1235 , cavity  1239  being dimensioned to receive substantially all but first end  1182  and shaft  1183  of motor  1181 . A pair of longitudinal lumens  1241  may be provided in body  1231 , lumens  1241  extending through proximal end  1233 , distal end  1235 , and side wall  1237 . Lumens  1241  may be aligned with corresponding threaded cavities  1242  in body  1105  so that distal end  1235  of body  1231  may be fixed to proximal end  1109  of body  1105  using screws  1243  inserted through body  1231  and into cavities  1242 . A groove  1245  may extend longitudinally from proximal end  1233  to distal end  1235  along the top surface of side wall  1237 . Groove  1245  may be aligned with groove  1131  of body  1105  in order to receive a corresponding portion of housing  1021  of morcellator assembly  1013 . 
     Drive assembly  1015  may further comprise an endplate  1251 . Endplate  1251 , which may be a unitary structure made of a rigid polymer or metal, may be a generally disc-shaped structure shaped to include a retaining loop  1253  at its top. Retaining loop  1253  may be dimensioned to receive the proximal end of housing  1021  of morcellator assembly  1013 . A pair of openings  1255  may be provided in endplate  1251 . Openings  1255  may be aligned with corresponding threaded cavities  1257  in body  1231  so that endplate  1241  may be fixed to proximal end  1233  of body  1231  using screws  1259  inserted through endplate  1241  and into cavities  1257 . 
     Drive assembly  1015  may further comprise a cover  1261 . Cover  1261 , which may be a unitary structure made of a rigid polymer or metal, may be in the shape of a half-pipe having a proximal end  1263  and a distal end  1265 . Cover  1261  may be dimensioned to complement side walls  1111  and  1207  of bodies  1105  and  1201 , respectively. In addition, cover  1261  may be fixed to body  1105  with a screw  1267  inserted through an opening  1269  in cover  1261  and into a corresponding cavity  1271  in proximal end  1109  of body  1105  and with a screw  1273  inserted through an opening  1275  in cover  1261  and into a corresponding cavity  1277  in distal end  1107  of body  1105 . Additionally, cover  1261  may be fixed to body  1201  by joining cover  1261  to a block  1281  using a screw  1283  and by joining block  1281  to distal end  1203  of body  1201  using a pair of screws  1285 . 
     Referring back now to  FIG. 27 , vacuum assembly  1009  may include a specimen collection container  1291  and a vacuum source  1292 . The distal end of an evacuation tube  1293  may be inserted over fitting  1097  and may be secured thereto by a friction fit, and the proximal end of evacuation tube  1293  may be coupled to a first port  1294  of container  1291 . The distal end of a tube  1295  may be coupled to a second port  1296  of container  1291 , and the proximal end of tube  1295  may be coupled to vacuum source  1292 . In this manner, vacuum source  1292  may be used to apply suction to device  1008 , and any withdrawn tissue, liquids or similar matter suctioned through device  1008  may be collected in container  1291 . 
     Control unit  1010 , which may be coupled to a source of electricity, such as an AC wall outlet, using a power cord (not shown), may include electronics (not shown) for controlling the operation of motors  1151  and  1181  using a cable  1298 - 1  connected to cables  1159  and  1189 . A foot pedal  1297  may be coupled to control unit  1010  by a cable  1298 - 2  and may be used as a power switch to selectively activate or de-activate motors  1151  and  1181 . Control unit  1010  may further include a vacuum sensor  1299 , which may be coupled to container  1291  by a tube  1300 , so that the pressure within container  1291  may be monitored by control unit  1010 . In this manner, a sudden increase in vacuum pressure may indicate that a clog has occurred. The presence of a clog may be indicated via an alarm (not shown) located on control unit  1010 . The detection of a clog is often a clear indication that the further operation of device  1008  may only aggravate the clogging situation and that a cessation of tissue removal may be necessary. Control unit  1010  may be configured to synchronize actuation of drive assembly  1015  with actuation of vacuum source  1292 . In this manner, turning on drive assembly  1015  will turn on vacuum source  1292  at the same time. Correspondingly, vacuum source  1292  may be deactivated whenever drive assembly  1015  is turned off. 
     In use, the distal end of a hysteroscope may be inserted transcervically into a patient, and a suitable fluid may be conducted through the inlet fluid port of the hysteroscope into the uterus until the uterus is distended. Observation of the uterus and detection of fibroids or other abnormal gynecological tissues may then be performed using the visualization channel of the hysteroscope. The distal ends of outer tubular member  1076  and inner tubular member  1077  may be inserted through a working channel of the hysteroscope and into the uterus, with the remainder of system  1007  remaining proximal to the hysteroscope. Device  1008  may then be manipulated so that window  1089  of outer tubular member  1076  may be positioned in proximity to the fibroid or other targeted tissue. Next, vacuum source  1292  may be operated so as to cause suction to be applied to inner tubular member  1077 , thereby drawing tissue into outer tubular member  1076  through window  1089 . In addition, motors  1151  and  1181  may be operated so as to cause inner tubular member  1077  simultaneously to rotate and to oscillate back and forth translationally within outer tubular member  1076 , thereby causing the tissue drawn through window  1089  to be cut. The cut tissue may then be suctioned from the patient through inner tubular member  1077  by means of the aforementioned suction and, thereafter, collected in container  1291 . Once the fibroids or other targeted tissues have thus been removed from the patient, vacuum source  1292  and motors  1151  and  1181  may be turned off, device  1008  may be withdrawn from the hysteroscope, and the hysteroscope may be withdrawn from the patient. Morcellator assembly  1013  may then be detached from drive assembly  1015  and disconnected from vacuum source  1292 . Morcellator assembly  1013  may be designed to be a single use device and, if so, may be disposed of after being used on a patient. By contrast, drive assembly  1015  may be used on a number of different patients prior to its disposal, with a different morcellator assembly  1013  preferably being used with each patient. 
     It should be noted that, although the above-discussion contemplates inserting device  1008  through the working channel of a hysteroscope, one may insert device  1008  transcervically into the uterus without the use of a hysteroscope. In such a situation, fluid may be administered transcervically to the uterus by a fluid dispensing device in order to distend the uterus, and, thereafter, observation of the uterus may be accomplished, for example, by ultrasonic imaging using an ultrasonic probe inserted transcervically into the uterus. Such an ultrasonic probe may be separate from device  1008  or may be integrated into device  1008 . Alternatively, imaging of the uterus may be performed by MRI imaging. 
     Referring now to  FIG. 30 , there is shown a fragmentary exploded perspective view of an alternate tissue removal device adapted for use in system  1007 , said tissue removal device being represented generally by reference numeral  1450 . For simplicity and clarity, certain aspects of device  1450  not important to an understanding of the invention are neither shown nor described herein. 
     Device  1450  may be similar in most respects to device  1008 , the principal differences between the two devices being that carriage  1193  and translational coupling block  1061  of device  1008  may be replaced with carriage  1461  and translational coupling block  1463 , respectively, of device  1450 . Carriage  1461  of device  1450  may be similar in many respects to carriage  1193  of device  1008 , the principal difference between the two carriages being that carriage  1461  may include an upwardly biased spring-loaded pin  1465 . Translational coupling block  1463  of device  1450  may be similar in many respects to translation coupling block  1061  of device  1008 , the principal differences between the two blocks being that (i) translation coupling block  1463  may be shaped to include a cavity  1467  adapted to receive pin  1465  and (ii) translation coupling block  1463  may be shaped to include ramped surfaces  1469 - 1  and  1469 - 2  sloping downwardly towards the open end of cavity  1467  from the proximal and distal ends, respectively, of translation coupling block  1463 . In use, the morcellator assembly, which comprises translation coupling block  1463 , may be attached to the drive assembly, which comprises carriage  1461 , and the translational motor of device  1008  may be actuated to move carriage  1461  translationally back and forth one complete cycle. Regardless of where carriage  1461  and translational coupling block  1463  may be initially positioned translationally relative to one another, as carriage  1461  is moved translationally one complete cycle, pin  1465  is automatically assured of being aligned with cavity  1467 . For example, if pin  1465  is initially positioned proximally relative to translation coupling block  1463 , as carriage  1461  is moved distally, the top surface of pin  1465  travels across ramped surface  1469 - 1  and is then received in cavity  1467 . One advantage of this arrangement is that pin  1465  and cavity  1467  need not be aligned with one another as the morcellator assembly and the drive assembly are attached to one other. As can be appreciated, because the morcellator assembly may be a single-use item whereas the drive assembly may be a reusable item, pin  1465  and cavity  1467  may not initially be aligned with one another. 
     Referring now to  FIGS. 31( a ) and 31( b ) , there are shown fragmentary, partially exploded, perspective views of another alternate tissue removal device adapted for use in system  1007 , said tissue removal device being represented generally by reference numeral  1500 . For simplicity and clarity, certain aspects of device  1500  not important to an understanding of the invention are neither shown nor described herein. 
     Device  1500  may comprise a morcellator assembly  1513  and a drive assembly  1515 . Morcellator assembly  1513  and drive assembly  1515  may be similar in most respects to morcellator assembly  1013  and drive assembly  1015 , respectively, the principal differences between the respective morcellator assemblies and drive assemblies being that morcellator assembly  1513  and drive assembly  1515  may be detachably matingly secured to one another by means of a detent  1517  provided on morcellator assembly  1513  and a slot  1519  provided in drive assembly  1515 . Accordingly, when one wishes to use device  1500 , detent  1517  of morcellator assembly  1513  is preferably inserted into slot  1519  of drive assembly  1515 , thereby physically and operatively coupling together morcellator assembly  1513  and drive assembly  1515 . Device  1500  may then be used in the same manner discussed above in connection with device  1008 . After device  1500  has been used, morcellator assembly  1513  may be separated from drive assembly  1515 , for example, by pulling apart their respective proximal ends until detent  1517  is removed from slot  1519 . If desired, morcellator assembly  1513  may then be disposed of whereas drive assembly  1515  may be reused. 
     Referring now to  FIG. 32 , there is shown a fragmentary, partially exploded, perspective view of another alternate tissue removal device adapted for use in system  1007 , said tissue removal device being represented generally by reference numeral  1600 . For simplicity and clarity, certain aspects of device  1600  not important to an understanding of the invention are neither shown nor described herein. 
     Device  1600  may comprise a morcellator assembly  1613  and a drive assembly  1615 . Morcellator assembly  1613  and drive assembly  1615  may be similar in most respects to morcellator assembly  1013  and drive assembly  1015 , respectively, the principal differences between the respective morcellator assemblies and drive assemblies being that morcellator assembly  1613  and drive assembly  1615  may be detachably secured to one another by means of hooks  1617  provided on morcellator assembly  1613  near its distal end and corresponding slots  1619  provided in drive assembly  1615  near its distal end. In addition, drive assembly  1615  may further comprise a spring retention member  1621  at its proximal end for engaging the proximal end of morcellator  1613 . Accordingly, when one wishes to use device  1600 , hooks  1617  of morcellator assembly  1613  are preferably inserted into slots  1619  of drive assembly  1615  and then spring retention member  1621  engages the proximal end of morcellator assembly  1613 , thereby physically and operatively coupling together morcellator assembly  1613  and drive assembly  1615 . Device  1600  may then be used in the same manner discussed above in connection with device  1008 . After device  1600  has been used, morcellator assembly  1613  may be separated from drive assembly  1615 , for example, by pulling apart their respective proximal ends until hooks  1617  are removed from slots  1619 . If desired, morcellator assembly  1613  may then be disposed of whereas drive assembly  1615  may be reused. 
     Referring now to  FIG. 33 , there is shown a fragmentary, partially exploded, perspective view of another alternate tissue removal device adapted for use in system  1007 , said tissue removal device being represented generally by reference numeral  1700 . For simplicity and clarity, certain aspects of device  1700  not important to an understanding of the invention are neither shown nor described herein. 
     Device  1700  may comprise a morcellator assembly  1713  and a drive assembly  1715 . Morcellator assembly  1713  and drive assembly  1715  may be similar in many respects to morcellator assembly  1013  and drive assembly  1015 , respectively, the principal differences between the respective morcellator assemblies and drive assemblies being that (i) morcellator assembly  1713  may be shaped to include a cavity  1717  and (ii) drive assembly  1715  may be shaped to be removably received within cavity  1717  of morcellator assembly  1713 . (Although not shown, morcellator assembly  1713  and/or drive assembly  1715  preferably includes a mechanism for releasably retaining drive assembly  1715  within cavity  1717 .) Accordingly, when one wishes to use device  1700 , drive assembly  1715  is preferably inserted into cavity  1717  of morcellator assembly  1713  until morcellator assembly  1713  and drive assembly  1715  are physically and operatively coupled to one another. Device  1700  may then be used in the same manner discussed above in connection with device  1008 . After device  1700  has been used, drive assembly  1715  may be withdrawn from cavity  1717  of morcellator assembly  1713 . If desired, morcellator assembly  1713  may then be disposed of whereas drive assembly  1715  may be reused. 
     Although the present invention has been discussed above in the context of removing tissue from within a patient&#39;s uterus, it should be understood that there may be situations in which it may be desirable to remove fibroids or other tissue located on the exterior of a patient&#39;s uterus or elsewhere within a patient. In such situations, it may be desirable to access the targeted tissue by laparoscopy. Unfortunately, however, one cannot simply apply suction in this type of case to draw the tissue into the resection window of the device because the tissue would not be bathed in a liquid, but rather, would simply be surrounded by air. Therefore, according to the present invention, one approach to this problem is to deliver a suitable material to the targeted tissue, which may then be used, with the application of suction, to create a seal to promote the drawing of the targeted tissue into the resection window of the device. Referring now to  FIG. 34 , there is shown an embodiment of a device designed for such a purpose, the device being represented generally by reference numeral  1800 . Certain aspects of device  1800  not important to an understanding of the invention are neither shown nor described herein. 
     Device  1800  may be similar in certain respects to device  6 . One difference between the two devices is that device  1800  may comprise an inner tubular member  1803  and an outer tubular member  1805 . Inner tubular member  1803  and outer tubular member  1805  may be similar to inner tubular member  77  and outer tubular member  76 , respectively, of device  6 , except that (i) outer tubular member  1805  may comprise a port  1807  adapted to receive a suitable liquid or gel (e.g., water, glycine, a thixotropic gel, etc.) from a supply (not shown) and (ii) inner tubular member  1803  may have an outer diameter that is about 0.005-0.006 inch less than the inner diameter of outer tubular member  1805  (as opposed to the about 0.002 inch of device  6 ) to permit the liquid or gel delivered to outer tubular member  1805  through port  1807  to be delivered to the targeted tissue through a resection window  1809 . 
     An alternate tissue removal device to device  1800  is shown in  FIG. 35 , said alternate tissue removal device being represented generally by reference numeral  1900 . Certain aspects of device  1900  not important to an understanding of the invention are neither shown nor described herein. 
     Device  1900  may be similar in most respects to device  6 , the principal difference between the two devices being that, whereas device  6  may comprise outer tubular member  76 , device  1900  may comprise an outer tubular member  1903 . Outer tubular member  1903  may be similar to outer tubular member  76 , except that outer tubular member  1903  may be additionally shaped to include a channel  1905  having a proximal input port  1907  and a distal output port  1909 . Input port  1907  may be adapted for connection to a supply (not shown) for receipt of a suitable liquid or gel (e.g., water, glycine, a thixotropic gel, etc.). Distal port  1909  may be positioned proximate to a resection window  1911 . 
     The embodiments of the present invention described above are intended to be merely exemplary and those skilled in the art shall be able to make numerous variations and modifications to it without departing from the spirit of the present invention. All such variations and modifications are intended to be within the scope of the present invention as defined in the appended claims.