Abstract:
A dermabrasion instrument includes an outer member and an inner member rotatably disposed in the outer member with an abrading member of the inner member exposed from the outer member. An aspirating passage in the abrading member establishes communication with an aspirating channel of the inner member from externally of the abrading member so that debris from abrasion of the skin by the abrading member is evacuated through the inner member. The outer member may include a shield disposed over the abrading member to contain the debris. The instrument may include an irrigating port for discharging irrigating fluid adjacent the abrading member. A dermabrasion instrument assembly includes an abrading instrument releasably coupled to a powered surgical handpiece. The instrument has an aspirating channel and the handpiece has a suction port connectible with a source of suction to effect evacuation of debris through the abrading instrument and the handpiece. A method of dermabrasion includes the steps of rotating an inner member of an abrading instrument within an outer member of the instrument to rotate an abrading member of the inner member, abrading the skin with the rotating abrading member and aspirating debris from abrasion through the inner member.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATION 
     This application claims priority from prior provisional patent application Ser. No. 60/130,655 filed Apr. 23, 1999, the disclosure of which is incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to instruments, instrument assemblies and methods for abrasively removing the surface layer of the skin to treat various surface defects therein and, more particularly, to dermabrasion instruments, instrument assemblies and methods wherein the dissemination of debris is avoided. 
     2. Brief Discussion of the Related Art 
     Abrasively removing the external surface layer of skin has been used to treat various surface defects in the skin. Removal of the surface layer of the skin by high-speed sanding is referred to as dermabrasion or surgical planing of the skin. During a typical dermabrasion procedure, the surface layer of the skin is removed using an abrading instrument with a rotating abrading member, typically a diamond fraise or wire brush rotated at high speed. 
     Abrasive methods can be used effectively for scar revision, tattoo removal, skin biopsy, wrinkle reduction and keratosis, for example. Dermabrasion is a preferred treatment for various types of acne scars. It is particularly effective for removing or reducing scars having a saucer or piepan contour, i.e., broad, relatively shallow scars with either tapering edges or a small drop-off between the edges and the floor of the scar. Dermabrasion is also highly effective in eliminating or reducing facial wrinkles, particularly around the mouth. 
     Conventional abrading instruments, instrument assemblies and methods have numerous disadvantages, however. A primary disadvantage is that the rotating abrading member disseminates or throws skin debris about the operating room making a mess and creating contamination problems for medical personnel. The problem of dissemination of skin debris is exacerbated due to the skin debris being relatively dry and, therefore, more likely to be thrown or scattered about. Other disadvantages include the inability to aspirate or remove skin debris from a dermabrasion site through the abrading instrument, the lack of active cooling of the rotating abrading member and the potential for clogging of the abrading instrument. 
     U.S. Pat. No. 5,707,383 discloses a surgical abrading instrument used to remove soft tissue in the middle ear. The surgical abrading instrument includes an abrading member mounted on a shaft having a proximal end connectible with a motorized handpiece used to rotate the shaft and, therefore, the abrading member. The dissemination of debris about the operating room is not a problem since the abrading member is used inside the ear. 
     SUMMARY OF THE INVENTION 
     Accordingly, a primary object of the present invention is to overcome the aforementioned disadvantages of conventional abrading instruments, instrument assemblies and methods of dermabrasion. 
     Another object of the present invention is to prevent skin debris from becoming scattered during a dermabrasion procedure by containing the skin debris at the dermabrasion site. 
     It is another object of the present invention to remove skin debris from a dermabrasion site in a controlled manner during a dermabrasion procedure. 
     A further object of the present invention is to wet skin debris in a dermabrasion procedure to promote containment of the skin debris. 
     It is also an object of the present invention to remove skin debris from a dermabrasion site through an abrading instrument performing the dermabrasion. 
     An additional object of the present invention is to actively cool an abrading member of an abrading instrument during a dermabrasion procedure. 
     The present invention has as another object to avoid clogging of an abrading instrument during a dermabrasion procedure. 
     Some of the advantages of the present invention are that the abrading instrument can be used with various conventional powered surgical handpieces to form an instrument assembly, the abrading member can have various configurations, abrasiveness can be imparted to the abrading member in various different ways, the abrasiveness of the abrading member can be varied to provide optimal abrasiveness for particular dermabrasion procedures, contamination problems for operating personnel are greatly reduced, the breathing in of debris by operating personnel is avoided, an air filtration system in the operating room for containment of debris is not needed, and the dermabrasion procedure can be performed as an out-patient procedure. 
     These and other objects, advantages and benefits are achieved with the present invention as generally characterized in a dermabrasion or abrading instrument for surgical abrasion of a surface of the skin and including an outer member and an inner member rotatably disposed in the outer member with an abrading member or tip of the inner member exposed from the outer member. The abrading member is adapted to abrade a surface of the skin with which the abrading member is contacted while being rotated relative to the outer member. The inner member includes a shaft and the abrading member disposed at a distal end of the shaft. The shaft has a lumen therethrough, and the abrading member has an aspirating passage establishing communication with the lumen from externally of the abrading member. The lumen is connectible with a source of suction to draw debris, produced by abrasion of the surface of the skin, into the aspirating passage for removal through the lumen. In a preferred abrading instrument, the outer member includes a shield covering a portion of the abrading member to contain dissemination of the debris due to centrifugal force of the abrading member. An optional irrigating port can be provided in the instrument to discharge an irrigating fluid toward the abrading member whereby the debris is wetter to promote containment thereof. 
     A dermabrasion or abrading instrument assembly according to the present invention is generally characterized in an abrading instrument and a powered surgical handpiece. The abrading instrument includes an outer member and an inner member rotatably disposed in the outer member with an abrading member or tip of the inner member exposed from the outer member. The inner member includes a shaft and the abrading member disposed at a distal end of the shaft. The shaft has a lumen therethrough in communication with an aspirating passage in the abrading member. The abrading member is adapted to abrade a surface of the skin contacted by the abrading member while the abrading member is rotated relative to the outer member. The powered surgical handpiece is releasably connectible with the inner and outer members to rotate the inner member relative to the outer member. The handpiece includes a suction port connectible with a source of suction to establish suction in the lumen of the shaft by which debris, generated from abrasion of the skin, is drawn into the aspirating passage for evacuation through the shaft and the handpiece. 
     A method of dermabrasion according to the present invention includes the steps of rotating an inner member of an abrading instrument within an outer member of the abrading instrument to rotate an abrading member or tip of the inner member that is exposed from the outer member, contacting a surface of the skin with the rotating abrading member, abrading the surface of the skin with the abrading member and aspirating debris, produced by abrasion of the skin, through the inner member. A preferred method includes the steps of containing the debris with a shield of the outer member. Optionally, the dermabrasion method includes the step of wetting the debris. 
     The foregoing and other objects and advantages can be accomplished individually or in combination using the dermabrasion instrument, instrument assembly and method according to the present invention. Other objects and advantages of the present invention will become apparent from the following description of the preferred embodiments taken in conjunction with the accompanying drawings, wherein like parts in each of the several figures are identified by the same reference numerals. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front perspective view of an abrading instrument according to the present invention mounted on a powered surgical handpiece to form an abrading instrument assembly. 
     FIG. 2 is an exploded top view of the abrading instrument shown in FIG.  1 . 
     FIG. 3 is a side sectional view of the outer member of the abrading instrument shown in FIG.  1 . 
     FIG. 4 is a side sectional view of the inner member of the abrading instrument shown in FIG.  1 . 
     FIG. 5 is an enlarged fragmentary view of the distal end of the abrading instrument shown in FIG.  1 . 
     FIG. 6 is a sectional view of the abrading instrument taken through line  6 — 6  in FIG.  5 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A dermabrasion or abrading system or instrument assembly  10  according to the present invention, as illustrated in FIG. 1, includes a dermabrasion or abrading instrument or abrader  12  attached to a powered surgical handpiece  14 . Abrading instrument  12  includes an outer member  16  which is held stationary by the handpiece  14  and an inner member  18  which is disposed at least partly within the outer member and rotated by the handpiece to remove the surface layer of the skin. Skin debris generated during a dermabrasion procedure is contained at the surgical or dermabrasion site by the outer member and is drawn into the inner member for removal from the site when a source of suction is connected to the handpiece. While a particular handpiece is shown, it will be appreciated that the abrading instrument can be configured for use with any conventional powered surgical handpiece. 
     As best seen in FIG. 2, outer member  16  includes an outer tubular member or outer shaft  20  and a shield  22  mounted at a distal end of the outer shaft. Outer shaft  20  is of hollow, cylindrical configuration to define a lumen therethrough and has a knurled surface  24  at a proximal end thereof for receiving a hub (not shown) of the type which releasably mounts a powered surgical handpiece in a stationary manner. Shield  22  includes an arcuate member connected to the distal end of outer shaft  20  by a generally frustoconical flange or shoulder  26  of increasing diameter in the distal direction. As shown in FIG. 4, the distal and proximal ends of outer shaft  20  are open, with the open distal end thereof communicating with the interior of shield  22 . In particular, the open distal end of outer shaft  20  opens into the interior of the frustoconical shoulder  26  and communicates with the space  23  defined by the arcuate member, the interior of shield  20  being defined by the space  23  and the interior of sholder  26 . As shown in FIGS. 1 and 2, a distal end of shield  22  is open to the space  23  and is defined by an arcuate distal edge  25  of the arcuate member. The shield has straight side edges  27  extending proximally from opposite ends, respectively, of the arcuate distal edge  25  and has an arcuate proximal edge  29 . The arcuate proximal edge  29  is disposed at an angle to the side edges  27  and has opposite ends connected to the side edges  27 , respectively. The side edges  27  extend parallel to a central longitudinal axis of the outer member  16 . The open distal end of shield  22  and the open proximal end of outer shaft  20  define distal and proximal ends, respectively, for the outer member  16 . 
     Referring to FIG. 3, an optional irrigating tube, port or channel  28  is shown extending conformingly along an outer surface of outer member  16  from a coupling  30  at a proximal end of tube  28  to a closed distal end  32  disposed along the arcuate member of shield  22 , the distal end  32  being disposed near the distal end of shield  22 . Coupling  30  forms an acute angle with the outer member relative to the proximal direction and is shown as a hose adapter which can be connected with a source of irrigating fluids (not shown). For example, the hose adapter can be connected to an end of a length of flexible tubing carrying irrigating fluid from the irrigating fluid source. At least one and, preferably, a pair of irrigating outlets  34 , are formed in tube  28  near its distal end  32  in alignment with one or more irrigating inlets  36  formed in shield  22  to permit an irrigating fluid such as water to flow from the irrigating tube  28  toward an abrading member or tip of the instrument and toward a dermabrasion site via the shield so as to cool the abrading member and improve debris containment by wetting the skin debris. The irrigating tube is fixedly attached to the outer member, for example by laser welding the tube to the outer member at a plurality of locations. 
     Referring again to FIG. 2, it can be seen that inner member  18  includes an inner tubular member or inner shaft  38  and the abrading member or tip  40  mounted at a distal end of the inner shaft  38 . Inner shaft  38  is tubular or of hollow, cylindrical configuration with a knurled surface  42  at a proximal end thereof for receiving a hub (not shown) of the type which can be releasably mounted for rotation by the powered surgical handpiece. Inner shaft  38  is configured to fit telescopically within outer shaft  20  and, as best seen in FIG. 4, the inner shaft  38  is of hollow, cylindrical configuration with open distal and proximal ends to define an aspirating or suction channel, passage or lumen  44  along its length which communicates with a source of suction via a coupling  46  on handpiece  14  when the abrading instrument is attached to the handpiece as shown in FIG.  1 . Abrading member or tip  40  is a hollow member defining or enclosing an interior in communication with the aspirating channel  44 . Abrading tip  40  has an abrasive outer surface  48  and one or more aspirating passages, ports or openings  50  formed through the abrasive surface. In the case of abrading instrument  12 , the abrasive outer surface  48  extends along or covers the entire exterior of tip  40 . The aspirating passages  50  establish communication with the aspirating channel  44  from externally of the abrading tip so that skin debris can be drawn into the channel  44  via the aspirating passages  50  and the interior of the abrading tip for removal from the surgical or dermabrasion site. The abrading tip shown in FIG. 4 includes a hollow, cylindrical central portion  52  of larger diameter than inner shaft  38 , a closed distal end defined by a rounded or hemispherical end wall  54  and an open proximal end defined by a tapered or frustoconical proximal portion  56  of decreasing diameter in the proximal direction. The cylindrical central portion  52  extends proximally from the rounded end wall  54 , and the tapered proximal portion  56  extends proximally from the cylindrical central portion to the distal end of inner shaft  38 . Aspirating passages  50  in the abrasive outer surface of the tip are shown as a plurality of longitudinal slots formed in the cylindrical portion  52  of the tip at angularly spaced locations about the circumference of the cylindrical portion. As shown in FIGS. 2 and 4, the slots extend longitudinally along the central portion  52  and are parallel to one another and to a central longitudinal axis of inner member  18 . The closed distal end of the abrading tip  40  and the open proximal end of inner shaft  38  define distal and proximal ends, respectively, of the inner member  18 . 
     Abrading instrument  12  can be assembled by inserting the proximal end of inner member  18  into the open distal end of outer member  16  and sliding the inner shaft into the outer shaft until the abrading tip  40  is disposed in the interior of the shield  22  and abuts the frustoconical flange  26  of the shield  22 . Appropriate hubs can then be mounted at the proximal ends of the inner and outer members, respectively, to permit the abrading instrument to be attached to a powered surgical handpiece. In the assembled condition or state, as shown in FIGS. 1,  5  and  6 , inner shaft  38  is disposed telescopically within outer shaft  20  thereby positioning abrading tip  40  concentrically within shield  22  with a small radial clearance C therebetween to prevent the abrasive surface of the abrading tip from contacting the inner surface of the shield when the tip is rotated relative to or within the shield. The abrading tip is disposed alongside the shield with a portion of the tip covered by the shield and another portion of the tip exposed from the shield to enable contact of the abrasive surface with a surface of the skin. The irrigating outlets are disposed adjacent the abrading tip so that irrigating fluid discharged therefrom is directed or discharged toward the tip. The shield is disposed between the irrigating tube and the tip with the irrigating inlets of the shield aligned with the irrigating outlets of the irrigating tube. As shown in FIG. 5, aspirating passages  50  on the side of the abrading tip are longitudinally aligned with the irrigating inlets  36  formed in the shield so that at least some of the irrigating fluid flows into the aspirating passages to help clear the aspirating passages of skin debris. In other words, aspirating passages  50  are disposed at the same or substantially the same longitudinal location as irrigating inlets  36  when the inner member  18  is inserted in the outer member  16  in the assembled condition. 
     The frustoconical flange  26  of shield  22  defines a mechanical stop or abutment surface which receives the proximal portion  56  of the tip  40  to limit or prevent the inner member from moving longitudinally, proximally relative to the outer member during operation so that the aspirating passages remain substantially in alignment with the irrigating inlets. As best seen in FIG. 6, shield  22  extends at least about 180 degrees around tip  40  so that portions of the abrasive surface facing the user are covered during use. In the case of abrading instrument  12 , the shield  22  extends slightly greater than 180 degrees around the tip  40  as seen in FIG.  6 . For maximum coverage, shield  22  can be configured to extend distally beyond the rounded end wall  54  of the tip as shown in FIG.  1 . Exposed portions of the tip, i.e., portions of the tip exposed from or not covered by the shield  22 , can then be used to surgically abrade or remove the surface layer of the skin. The rounded end wall  54 , cylindrical central portion  52  and frustoconical proximal portion  56  of the tip define multiple abrasive planes which can be used to sculpt the outer layer of the skin when the inner member is rotated during a dermabrasion procedure. The frustoconical flange  26  can be notched, cut out or shaped on the side that is contiguous with the side edges  27  to expose a greater portion of the frustoconical proximal portion  56  of the tip for maximum flexibility of use. In the case of abrading instrument  12 , for example, the angle of the proximal edge  29  results in greater exposure of the proximal portion  56 . Since the distal end of the shield is open, the distal end of the tip is also exposed for use. 
     The abrading instrument is releasably attached to the powered surgical handpiece  14  to form a dermabrasion or abrading system or instrument assembly as shown in FIG. 1 by coupling the hubs of the inner and outer shafts, respectively, with mating portions of the handpiece such that the outer member  16  is held stationary by the handpiece and the inner member  18  is rotated by the handpiece within the stationary outer member. Attachment of inner member  18  to handpiece  14  also places the aspirating lumen  44  of the inner member in fluid communication with suction port  46  on the handpiece so that a negative pressure can be created in the aspirating lumen simply by attaching a suction line to the handpiece suction port. If desired, an irrigating fluid can be supplied to the abrading tip via irrigating tube  28  by connecting a hose, tubing, or the like to coupling  30  at the proximal end of the irrigating tube. 
     A typical dermabrasion or skin abrading method or procedure according to the present invention involves numbing the skin of a patient with a local anesthetic and removing the surface layer of the skin using abrading instrument  12 . Removal of the surface layer of the skin is accomplished by rotating inner member  18  relative to outer member  16  to cause tip  40  to rotate within shield  22  and placing the rotating tip against the skin with the shield disposed between the tip and the user, i.e. the person performing the dermabrasion on the patient. The speed of rotation of the tip can be fixed or controlled by the user using a foot pedal or controls on the handpiece. Abrading tip  40  generates debris as the surface layer of the skin is removed, the debris generally flying off the tip in a radial direction due to the centrifugal force generated by rotation of the tip; however, the placement of shield  22  between the tip and the user tends to contain the debris at the surgical or dermabrasion site adjacent aspirating passages  50  in the abrasive surface of the tip. Connection of the handpiece with a source of suction causes the debris to be drawn into the interior of the tip via the aspirating passages  50  for removal through the aspirating lumen of the inner member. Containment of skin debris at the surgical site can be further enhanced by connecting the abrading instrument to a source of an irrigating fluid so that irrigating fluid is supplied at the abrading tip, via the irrigating outlets  34  in irrigating tube  28  and the irrigating inlets  36  in shield  22 , to wet the skin debris. More particularly, the irrigating fluid is discharged from the irrigating inlets  36  toward the abrading tip and the site of dermabrasion. The aspirating passages  50  and the irrigating fluid also effect cooling of the abrading tip for improved results. Also, the aspirating passages  50  move past the irrigating inlets  36  as the tip is rotated within the shield, and the irrigating fluid discharged from inlets  36  helps keep the passages  50  free from clogging. Some of the irrigating fluid is drawn into the interior of the tip via the passages  50  for removal through the lumen of the inner member, thusly enhancing aspiration of the skin debris from the surgical or dermabrasion site and inhibiting build up of skin debris in the passages  50 . The dermabrasion instrument, instrument assembly and method according to the present invention can be used for a number of purposes including, but not limited to, scar revision, skin biopsy, wrinkle reduction and keratosis. Generally, such procedures can be performed on an outpatient basis. 
     In an exemplary embodiment, the overall length of outer member  16  is about 2.95 inches and the overall length of inner member  18  is about 4.62 inches, with outer shaft  20  being formed of type 304L stainless steel tubing having an outer diameter of about 0.190 inch and a wall thickness of about 0.03 inch. Shield  22  is formed of type  303  stainless steel with about the same wall thickness as the outer shaft, and the arcuate member thereof has about twice the radius of curvature of the outer shaft. The length of the frustoconical flange and the arcuate member in the exemplary embodiment are about 0.206 inch and about 0.458 inch, respectively. The irrigating tube  28  in the exemplary embodiment is formed of type 304L stainless steel tubing with an inner diameter of about 0.042 inch, an outer diameter of about 0.058 inch, and a closed distal end proximally spaced about 0.10 inch from the distal end of the shield. Irrigating inlets  36  are shown as longitudinally aligned elongate slots in the exemplary embodiment, with lengths of about 0.094 inch and widths of about 0.025 inch, and with a longitudinal spacing of about 0.03 inch therebetween. Inner shaft  38  in the exemplary embodiment is formed of type 304 stainless steel tubing with an inner diameter of about 0.125 inch and an outer diameter of about 0.146 inch. Tip  40  in the exemplary embodiment is formed of type 303 stainless steel with an outer diameter of about 0.297 inch, an overall length of about 0.589 inch, and an abrasive surface formed over the entire tip by a coating of 40/60 or 60/80 diamond grit. Passages  50  in the exemplary embodiment are about 0.275 inch long and about 0.020 inch wide. An exemplary radial clearance C between the abrading tip and the shield is about 0.06 inch. 
     The abrading instrument according to the present invention can be configured for use with any powered surgical handpiece including, but not limited to, the Xomed STRAIGHTSHOT® handpiece shown in FIG.  1  and described in U.S. patent application Ser. Nos. 09/005,010, 09/005,012, 09/005,014 and 09/005,189, all filed on Jan. 9, 1998, the disclosures of which are incorporated herein by reference. 
     The inner and outer members can be made of any suitable medical grade materials but are preferably made of stainless steel. The abrading tip can have any suitable configuration for abrading the outer surface of the skin including, but not limited to, configurations wherein the tip includes brushes, bristles, wire mesh or diamond fraises. When the abrading tip is coated with diamond or other types of grit, the grit can be fine or coarse or can be of any other suitable size. All or part of the outer surface of the abrading tip can be rendered abrasive. While a generally cylindrical abrading tip is shown and described herein, it will be appreciated that any useful shape can be used including, but not limited to, round, conical, frustoconical, pear shaped, and wheel-like shapes. The abrading tip can be formed with a single aspirating passage or port formed therein or with plural aspirating passages or ports formed therein. The size and shape of the aspirating passages can be varied. For example, the aspirating passages can be elongate slots, circular holes or rectangular apertures. 
     The irrigating inlets and outlets can have any suitable shape and size including, but not limited to, the slotted configuration shown. The abrading instrument can be formed with a single irrigating inlet and outlet or with plural irrigating inlets and outlets as shown. The abrading instrument can be operated without aspiration or irrigation, with aspiration only, or with irrigation only. Furthermore, an aspirated abrading instrument can be operated without a shield. 
     The dimensions of the various components described herein are merely exemplary and can be varied dependent upon the nature of the skin defect being treated and the preference of the user. The inner member can be rotated at any suitable speed but is preferably rotated at about 1200 rpm to reduce the possibility of gouging and burning of the skin. 
     Inasmuch as the present invention is subject to many variations, modifications, and changes in detail, it is intended that all subject matter discussed above or shown in the accompanying drawings be interpreted as illustrative only and not be taken in a limiting sense.