Abstract:
An apparatus including a handle; a first tubular body coupled to the handle and a second tubular body comprising a polymer material coupled to a distal end of the first tubular body and the distal end defining a guide face, wherein the first tubular body and the second tubular body are co-linearly aligned and collectively define a first lumen therethrough extending from an entry port to the guide face; wherein the second tubular body has a dimension adequate for insertion into a uterus of a human subject, and wherein the guide face comprises an outside diameter less than an outside diameter of the second tubular body. Also, a method of using a hysteroscope having a single operating channel.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The application is a nonprovisional application of application Ser. No. 60/262,141, filed Jan. 12, 2001, entitled “Hybrid Insertion Arm for Endoscopically Assisted Embryo Implantation”. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The invention relates to generally to intra-uterine devices, including hysteroscopes and related devices for microsurgical use such as use in the field of embryo implantation. 
     2. Description of the Related Arts 
     Improving the success of in vitro fertilization (IVF) depends on many factors, one of which is the delivery or transfer of the embryo to the endometrial lining of the uterus and the successful implantation of the embryo therein. It is well known in the art that assisting an embryo to adhere to, or implant within, a pre-determined area of the endometrial lining of the uterine wall, as opposed to simply releasing the embryo into the uterus, will enhance the success of IVF, minimize the risk of tubal pregnancies and reduce high-order multiple births. 
     U.S. patent application Ser. No. 09/759,415, filed Jan. 12, 2001, titled “Method and Apparatus for Assisted Embryo Implantation,” describes a minimally invasive embryo transfer method, which, in one embodiment, describes a specially formed microcatheter to gently deliver one or more selected embryos into a pocket formed within the endometrial lining of a subject&#39;s uterus. 
     A microcatheter, such as described for use in the referenced document, is inserted typically by way of a hysteroscope. A hysteroscope is generally a specialized endoscopic device, for intrauterine use, which provides for direct or video observation of the interior of a subject&#39;s uterus and provides a platform for microsurgical instruments such as catheters by providing a channel or lumen through the device. Representative endoscopes are described in U.S. Pat. No. 6,006,002 issued to Motoki, et al.; U.S. Pat. No. 4,534,339 issued to Collins, et al.; and U.S. Pat. No. 4,203,430 issued to Takahashi. To enhance the field of vision of a hysteroscope within the uterus, often the uterus will be insufflated with a gas to distend the uterine walls. In addition to providing a channel or lumen through the device for instruments, prior art hysteroscopes may provide an additional channel or lumen for a gas introduction. A hysteroscopic device for performing a minimally invasive microsurgical intrauterine procedure such as an embryo implantation procedure should be small enough so that the subject&#39;s uterus may be accessed comfortably without inducing dilation. Multiple lumen devices tend to cause discomfort and are generally difficult to maneuver. What is needed is an improved endoscopic device that may provide a stable platform for use of such a microcatheter or other instrument. 
     SUMMARY OF THE INVENTION 
     A hysteroscope is disclosed. In one embodiment, a hysteroscope provides for minimally invasive operative access to the interior of the subject&#39;s uterus for instruments or insufflation via a single operative channel or lumen through an insertion arm of the device. To accomplish insufflation of a subject&#39;s uterus, a gas feed line is attached to a gas port on the hysteroscope which feeds into the operative channel. By using the same operative channel for gas insufflation and for instrument (e.g., microcatheter) insertion, the insertion arm of the hysteroscope may be minimized, permitting comfortable and easy uterine access as well as access without inducing dilation. Further features of embodiments of a hysteroscope described herein include an insertion arm having a distal tip with an edge radius that may tend to reduce the bluntness of the distal tip, and a hybrid rigid and flexible arm that may provide a more stable operative platform for microsurgery, such as the microsurgery of the endometrial lining and embryo implantation. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic, cross-sectional side view of one embodiment of a hysteroscope. 
     FIG. 2 is a cross-sectional side view of a portion of the hybrid insertion arm portion of the hysteroscope of FIG.  1 . 
     FIG. 3 is a cross-sectional view of the hysteroscope of FIG.  1  through line A—A′ of FIG.  2 . 
     FIG. 4 is a schematic, cross-sectional side view of another embodiment of a hysteroscope. 
     FIG. 5 is a partial cross-sectional view of the hysteroscope of FIG.  1  through line A—A′. 
     FIG. 6 is a cross-sectional side view of a portion of the hybrid insertion arm portion of the hysteroscope of FIG.  4 . 
     FIG. 7 is a cross-sectional view of the hysteroscope of FIG.  1  through line B—B′ of FIG.  6 . 
     FIG. 8 is a side view of a prior art microcatheter. 
     FIG. 9 is a side view of a hybrid microcatheter. 
     FIG. 10 is a first representative view of the hysteroscope being used for an embryo implantation procedure. 
     FIG. 11 is a second representative view of the hysteroscope being used for an embryo implantation procedure. 
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawings, illustrated in FIGS. 1-3 is one embodiment of a hysteroscope. During, for example, many types of embryo transfer procedures, hysteroscope  10  is inserted into a subject&#39;s uterus and used for direct, visual inspection of the endometrial lining and/or for embryo transfer or implantation. 
     Hysteroscope  10  is a two-part device, with operational section  11  at one end and hybrid insertion arm  12  at the other end. Operational section  11  is held by the operator during an intrauterine procedure, and a portion of hybrid insertion arm  12  is inserted into a subject&#39;s uterus. Supported on operational section  11  is eyepiece  13 , used to visualize inside a uterus; control knob  14  used to maneuver a control structure (e.g., one or more braided wires extending to hybrid insertion arm  12  to actuate hybrid insertion arm  12  (the actuation shown in ghost lines)); and a series of access ports  15 - 17  extending from operational section  11  through one or more lumens inside both proximal portion  18  and distal portion  19  which form hybrid insertion arm  12 . Hybrid insertion arm  12  is, in this embodiment, generally tubular and includes proximal portion  18  of a generally rigid material and distal portion  19  of a relatively flexible material (e.g., a polymer material). 
     The one or more lumens defined by access ports  15 - 17  extend through proximal portion  18  and distal portion  19  and exit or terminate at distal end  30  of distal portion  19  through guide face  31 . Included among the one or more lumens is operative channel or lumen  20 . Operative channel  20  extends between distal end  30  and, representatively access port  16 . Operative channel  20  has a diameter suitable for insertion of a microcatheter therethrough for the purpose of performing a microsurgical procedure. 
     In one embodiment, distal end  30  of hybrid insertion arm  12  has edge radius  32  (e.g., a rounded edge) to facilitate gradual and gentle insertion through a subject&#39;s cervix. Edge radius provides less trauma than a blunt ended instrument and is generally able to gain entry into a smaller opening than a blunt instrument. To further aid the operator during insertion, series of locator marks  33  may be added to an exterior of hybrid insertion arm  12  to help the operator gauge the position of hybrid insertion arm  12  within a subject&#39;s uterus. 
     Prior art hysteroscopes with wholly flexible insertion sections are often difficult to control precisely during an intrauterine procedure. In the case of an intrauterine microsurgical procedure, hybrid insertion arm  12 , having, in one embodiment, a rigid tubular proximal portion  18 , preferably constructed of a smooth material such as stainless steel, seamlessly grafted/bonded to flexible tubular polymer (plastic-like) distal portion  19 , is more easily maneuvered within a uterus and provides a more stable platform from which to perform the microsurgery and/or embryo implantation than from a wholly flexible hysteroscopic insertion arm. 
     Hybrid insertion arm  12  with both rigid proximal portion  18  and flexible distal portion  19  may be attached to a variety of hysteroscopic devices and should not be limited to being attached to, or supported by, operational section  11  detailed herein. 
     Often during an intrauterine procedure, uterine insufflation is desirable. Referring to FIG. 1, illustrated in hysteroscope  10  is gas port  15  which feeds into operational port  16  to operational channel  20 . By sharing operational channel  20  between instruments and insufflation gas, a diameter of insertion arm  12  may be minimized yet providing the insufflation function. 
     Illumination within a subject&#39;s uterus may be added via illumination train extending through lumen  35  of hysteroscope  10 . Lumen  35  extends, in one embodiment shown in FIGS. 1-3, between operational section  11  and hybrid insertion arm  12 . Access to lumen  35  is provided by light port  17  where a light source may be coupled, preferably remotely so as not to hinder an operator&#39;s maneuvering of the device. Representatively, one or more illumination fibers  21  may extend a sufficient distance in a proximal direction from access port  17  and be coupled to light source  45  at its proximal end, so that light source  45  may remain stationary (e.g., on a table top), while hysteroscope  10  is maneuvered. In one embodiment, one or more illumination fibers  21  is inserted through lumen  35  and terminates at distal end  30 . In one embodiment, one or more illumination fibers  21  includes a distal end of ground glass with a blunt or, as viewed, vertical cross-section. Preferably, the distal end of one or more illumination fibers  21  aligns (is co-extensive with) distal end  30 . Accordingly, in the embodiment where distal end  30  has a rounded edge, such rounded edge, in one embodiment, does not include the entire cross-section of distal end  30 . Referring to FIG.  2  and FIG. 3, guide face  31  has a blunt or, as viewed, a vertical profile (α of 90° ). In this embodiment, operational channel  20  and lumen  35  are disposed within a cross-section of guide face  31 . 
     In addition to an illumination train, hysteroscope  10  includes an image train. The visualization train includes lumen  36  extending between operational section  11  and hybrid insertion arm  12 . At the operational section end, eyepiece  13  is disposed within or coupled about lumen  36 . A video camera may alternatively be coupled about lumen  36  to provide video images of the uterus. At the hybrid insertion arm end, one or more lenses  37  is/are disposed within or coupled about lumen  36 . In the embodiment shown in FIGS. 1-3, lumen  36  including one or more lenses  37  is disposed within a cross-section of guide face  31 . An optical fiber may be disposed within lumen  36  in between the viewing device (e.g., eyepiece  13 ) and one or more lenses  37 . 
     FIG. 4 shows a schematic, cross-sectional view of another embodiment of a hysteroscope. In this embodiment, hysteroscope  100  includes operational section  111  at one end (a proximal end) and hybrid insertion arm  112  at a second end (a distal end). Hybrid insertion arm  112  is generally tubular (defining one or more lumens therethrough) and includes proximal portion  118  of a generally rigid material, such as stainless steel, and distal portion  119  of a relatively flexible material (e.g., a polymer material). Representatively, proximal portion  118  has a length on the order of about 8 to 10 cm with about an outside diameter (OD) on the order of 3 to 4 mm. Distal portion  119  has a representative length of 3 to 5 cm and a representative OD of 3 to 4 mm, preferably a representative length slightly smaller (at least toward distal end  130 ) than proximal portion  118 . 
     Referring to FIG. 4, operational section  111  includes handle portion  127 . Coupled to a distal end of handle portion  127  is lever holder  128 . Disposed within lever holder  128  is articulating lever  129  that is coupled through, for example, wire or braided cable members to distal portion  119 . Representatively, deflection of articulating lever  129  about lever holder  128  deflects distal portion  119  of hybrid insertion arm  112  to the same degree. In one embodiment, articulating lever  129  rotates about a single axis 60° in two directions (e.g., clockwise and counterclockwise) for a total range of deflection of 120°. 
     FIG. 5 shows a cross-section of lever holder  128  through line A—A′ of FIG.  4 . Lever holder  128  includes, in this embodiment, articulating lever  129  coupled to C-shaped wire mount  163  within primary lumen  125 . As viewed, two wire members  162 , such as braided wire members, are coupled to wire mount  163  at opposite sides thereof (e.g., 12 o&#39;clock and 6 o&#39;clock as viewed, respectively). Wire mount  163  is coupled to articulating lever  129  through lever holder  166 . 
     Referring again to FIG. 4, at a proximal end of handle portion  127  of hysteroscope  100  is access port  116 . Access port  116  provides access to operational channel or lumen  120 . Operational channel  120  extends through the device from operational section  111  to hybrid insertion arm  112  terminating at distal tip  130 . In this embodiment, access port  116  is axially aligned with operational channel  120 . In one regard, the axial alignment aids the insertion of instruments such as a microcatheter into operational channel  120 . 
     Also at a proximal end of handle portion  127  of hysteroscope  100  is a portion of illumination train  140  including illumination holder  144 . A plurality of illumination fibers (e.g., glass fibers) are disposed within illumination holder  144  and join operational channel  120  within handle  127 . As illustrated more clearly in FIG. 7 described below, in one embodiment, operational channel  120  and the plurality of illumination fibers are axially aligned and disposed within a primary lumen extending from operational section  111  to hybrid insertion arm  112 . Light post  142  is disposed at a distal end of illumination holder  144  and may itself be a light source to the illumination fibers or be coupled to a light source. For example, light source  145  may be located remotely so as not to inhibit an operator&#39;s use of the device. At a proximal end of illumination holder  144 , the illumination fibers are surrounded by tubing or sheathing and the tubing or sheathing is coupled to handle portion  127 . 
     Still referring to FIG. 4, at a proximal end of handle  127  is a portion of image train  155  including eyepiece  156 . Eyepiece  156  is coupled to lumen  136  (see FIGS. 6 and 7) which joins operational channel  120  within handle  127  and is axially aligned within a primary lumen extending from operational section  111  to hybrid insertion arm  112 . 
     Coupled at a proximal end of operational channel  120  is stopcock  126  to, in one position, seal or block operational channel  120  and, in another position, to allow insufflation gas or an instrument such as a microcatheter to be passed through operational channel  120 . In another embodiment, stopcock  126  may have three positions to, for example, provide individual access ports for an instrument and for insufflation gas. In one embodiment, stopcock  126  is sterilizable and, where desired, removable and replaceable. A microcatheter and/or insufflation gas, in one embodiment, may alternatively be introduced to operational channel  120  at entry port  116 . 
     FIG. 6 shows a schematic, cross-sectional side view of a distal end of hybrid insertion arm  112 . FIG. 7 shows a cross-section through line B—B′ of FIG.  6 . Each figure shows primary channel  125  extending through hybrid insertion arm  112  to distal end  130 . In one embodiment, primary channel  125  is a polymeric material of having a diameter on the order of 1.3 mm. Disposed within primary channel  125 , in this embodiment, is operational channel  120  and illumination lumen  136 . In a preferred embodiment, operational channel  120  has an inside diameter (ID) of about 1.5 mm or less, preferably 1.3 mm. Also disposed within primary channel  125  are a plurality of illumination fibers  180  (each having a representative diameter on the order of 0.12 mm) forming part of illumination train  140  extending back to illumination holder  144  and light post  142  and operational section  111 . Still further disposed in operational channel  120  is image lumen  136  which forms part of image train  155  and is coupled, in one embodiment, to eyepiece  156  in operational section  111 . Image fiber  157 , such as a 10K image fiber may be disposed in image lumen  136  and coupled to eyepiece  156 . At a distal end of image lumen  136  is one or more lenses  137 , such as a GRIN, ILH-.5-WD15 lens . 
     Disposed outside of primary channel  125 , preferably within a separate lumen or lumens or sheaths is co-axially disposed dumb bell  175  coupled (e.g., via adhesive) to distal end  130  of hybrid insertion arm  112 . Wires  162  are coupled to dumb bell  175  to provide for articulation of distal portion  119  of hybrid insertion arm  112  by articulating lever  129 . 
     Referring to FIG. 6, distal end  130  of hybrid insertion arm  112  has a rounded edge  132  and a blunt (e.g., vertical) guide face  131 . Accordingly, guide face  131  has a smaller diameter than the outside diameter of distal portion  119  of hybrid insertion arm  112 . It is appreciated that edge  132  need not be rounded but could be linearly-sloped. Primary channel  125  is disposed within blunt guide face  131  so that illumination fibers  180  (see FIG. 7) may terminate with a blunt edge at guide face  131 . Rounded edge  132  facilitates insertion into a subject. 
     To minimize the diameter of the hybrid insertion arm described in the above embodiments, and to allow for a reduced diameter of the one or more lumens therethrough, including a reduced diameter of an operative channel of the hysteroscope, an improved microcatheter, representatively for use in embryo transfer, implantation and intrauterine microsurgery has been developed. 
     A microcatheter is a flexible tube with a base section and a tip section. Shown in FIG. 8 is prior art microcatheter  200 . Prior art microcatheter  200  includes proximal portion (base portion)  201  and distal portion (tip portion)  202  typically formed of the same extruded polymer (plastic) material. One such prior art microcatheter is embryo transfer catheter manufactured by Cook OB/Gyn of Spencer, Ind. However, when prior art microcatheter  100  is reduced to an outside diameter of less than 0.833 mm, it has been observed to be too flexible and become nonfunctional when it encounters tissue. Flexing is illustrated by reference numeral  203 . 
     To overcome the flexibility problems, some manufacturers have produced “Teflon” based microcatheters which have greater wall strength and are less likely to bend. However, Teflon based microcatheters typically cannot be extruded with a tip diameter of less than 0.4 mm according to current techniques. Therefore, the trade-off for strength (rigidity) has been larger tip diameter. 
     Referring to FIG. 9, microcatheter  250  includes, in one embodiment, a proximal portion (base portion)  251  of, for example, a polycarbonate material having a diameter of about one (1) mm or less that is resistant to flexing (bending) and distal portion (tip portion)  252  of, for example, transparent polycarbonate material that is generally non-toxic to embryos. Distal portion  253  includes, in one embodiment, tip  252  of an interior diameter of about 400 micrometers (μm). Distal portion  253  is similar, in one respect, to a micropipette and tapers  254  towards tip  252 . Distal portion  253  and proximal portion  251  being of dissimilar, representatively extruded polymer materials, are bonded  255  together to form microcatheter  250 . Bonding methods include a sonic weld, solvents, heat, adhesive and other suitable methods. Microcatheter  250  both resists bending when it encounters tissue and provides reduced diameter tip  252 . Microcatheter  250  is also useful in-and-of-itself as a miniature microsurgical tool. 
     FIGS. 10 and 11 illustrate one embryo implantation procedure using, representatively hysteroscope  100  and microcatheter  250 . During an embryo implantation procedure, entry port  116  of hysteroscope  100  receives microcatheter  250  which is of adequate length to allow distal end  251  thereof to extend from guide face  131 . Hysteroscope  100  is inserted, either before or after receiving microcatheter  250 , into a subject&#39;s uterus “U”. Guide marks  133  on proximal portion  118  may be used as a reference for insertion depth. Light source  145  may illuminate a portion of the interior of the uterus and the portion of the uterus may be visualized by an operator through eyepiece  156 . Articulating lever  129  may be used to maneuver/position a distal end of hysteroscope  100  (and possibly microcatheter  250 ) to a selected visualized position. 
     Distal end  521  of the microcatheter  250  once positioned within uterus “U” can be used to perform microsurgery such as the formation of an implantation pocket “P” within the endometrial lining “L” (FIG.  11 ). With an implantation pocket “P” formed in the endometrial lining “L”, one or more embryos may be introduced through microcatheter  125 . 
     In the preceding detailed description, the invention is described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention as set forth in the claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.