Abstract:
An ergonomically superior endoscopic suction-irrigation instrument for surgery comprises a telescope sheath connected at an adjustable angle, preferably approximately 30°, to a vertically elongated handle having thumb-operated irrigation and suction valves and a hook for supporting the handle from the surgeon&#39;s hand when the surgeon&#39;s grip on the handle is loosened. The instrument is especially suited for sinus surgery.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority based upon provisional application No. 60/234897, filed Sep. 22, 2000. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates generally to surgery and more particularly to improvements in instruments used for suction, irrigation, or both in surgical procedures, for example sinus surgery. 
     Sinus surgery is typically carried out with the aid of an endoscope. The endoscope is inserted into a patient&#39;s nostril to enable the surgeon to observe a magnified view of the surgical field on a monitor connected to a video camera coupled to the endoscope. Nasal/sinus surgery is carried out in a confined, highly vascularized space. Therefore, there is significant splattering of blood and surgical debris onto the endoscope during the surgery. It is important to keep the endoscope lens clear of blood and surgical debris for optimal visualization of the surgical field. Typically, this is accomplished by irrigating the lens of the endoscope or by removing the scope from the nostril for manual cleaning. 
     The patient is normally under general anesthesia and in a supine position. The telescope is inserted into the nostril and manipulated to position the tip of the scope near the surgical site. The endoscope is typically handled by the surgeon using a finger grip in order to control the position of the endoscope against the forces exerted by the tissue structures and the attachments to the endoscope, such as a video camera head and cables, a fiber optic light carrier and irrigation tubes. This method of handling the endoscope has been found to cause fatigue, especially in longer surgical procedures. 
     Another problem encountered in conventional endoscopic sinus surgery is encumbered working space. The typical method of gripping the endoscope can limit the working space around the scope for the manipulation of other instruments. This encumbrance is increased when irrigation tubing and/or bulky hand pieces take space around the entrance to the nostril. 
     Existing pump-driven irrigation systems have foot-operated controls. Locating these controls among other foot-operated equipment, such as the electrosurgical unit and powered cutting devices, is distracting to the surgeon during surgery, since the surgeon must shift his or her position to operate the various controls. These devices are also cumbersome to set up and generally do not provide adequate fluid volume and pressure. 
     It is an object of this invention to address the aforementioned problems, and it is a general object of this invention to provide an ergonomically superior irrigation system for use in sinus surgery and in other surgical operations where irrigation and/or suction are required. 
     SUMMARY OF THE INVENTION 
     A preferred endoscopic instrument in accordance with the invention comprises a tubular sheath extending along a sheath axis, the sheath having an internal passage for receiving a telescope, the internal passage extending from a proximal, telescope-receiving opening to a distal tip, and a port for connection to suction and irrigation lines; a handle having a manually graspable external surface; a suction valve within the handle, the suction valve being connectible to a suction line and openable to provide communication between said port and the suction line; an irrigation valve within the handle, the irrigation valve being connectible to an irrigation line and openable to provide communication between said port and the irrigation line; manually operable controls on the handle for selectably opening the suction and irrigation valves; and a coupling rigidly connecting the handle to the sheath at an intermediate location along the length of the sheath between the proximal opening and the distal tip; wherein the handle is elongated along a handle axis and oblique relative to the sheath. Preferably, the coupling permits adjustment of the angle between the handle and the sheath. The sheath is releasably locked to the coupling, and rotatable, when released, about the sheath axis. The rotatability of the sheath allows for appropriate positioning of an angle or side-viewing telescope. 
     Other objects, details and advantages of the invention will be apparent from the following detailed description when read in conjunction with the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of an endoscopic instrument in accordance with a preferred embodiment of the invention, showing the telescope and telescope sheath as well as the handle and suction/irrigation valve assembly; 
     FIG. 2 is a right side elevational view of the handle and valve assembly; 
     FIG. 3 is a left side elevational view of the handle and valve assembly; 
     FIG. 4 is a front elevational view of the handle and valve assembly; 
     FIG. 5 is a perspective view of the handle and valve assembly; 
     FIG. 6 is a top plan view of the handle and valve assembly; 
     FIG. 7 is a bottom plan view of the handle and valve assembly; 
     FIG. 8 is a fragmentary sectional view illustrating the fluid connection between the handle and valve assembly and the telescope sheath; 
     FIG. 9 is an exploded view, partly in section, showing the telescope sheath and telescope sheath receiver; 
     FIG. 10 is a fragmentary sectional view showing details of the relationship between the interior of the telescope sheath and the tip of the telescope; and 
     FIG. 11 is a vertical section through the handle, illustrating the operation of the irrigation valve. 
    
    
     DETAILED DESCRIPTION 
     As shown in FIG. 1, the instrument  10  comprises a telescope sheath  12 , which is held in a coupling  14  connected to the lower end of an elongated handle  16 . 
     The telescope sheath  12  includes an elongated, hollow tube  18  having an opening at its distal end  20 . The sheath has, at its proximal end, a fitting  22  with an opening  24  into which a telescope can be inserted. The telescope used with this instrument typically comprises an eyepiece  27 , or alternatively, a miniature television camera (not shown). The eyepiece or camera is connected to the proximal end of a shaft  25 , having within it a system of lenses arranged to focus into the eyepiece or television camera a magnified image of the surgical field adjacent the tip of the telescope, which will be at the location of distal end  20  of the tube  18  when the instrument is fully assembled. A fiber optic light carrier is ordinarily provided in the shaft for illuminating the surgical field. 
     The telescope shaft  25  fits into the sheath  12 , extending almost to the opening at the distal end of the tube, as shown in FIG.  10 . The inside diameter of the tube  18  is slightly larger than the outside diameter of the telescope shaft  25 , providing an annular space for the flow of fluid. An annular clearance  29 , between the telescope shaft and the distal end of the tube, allows for the flow of irrigation fluid, usually saline solution, outward from the tip of the tube and for the return of fluid along with blood and debris, drawn into the tube by suction. Since the nasal cavity approximates an oval shape, the exterior of the tube is preferably oval shaped to minimize the interference of the tube with other surgical instruments passed along side the tube inside the nostril. The interior of the tube  18  at its distal end  20  is preferably curved inward to direct irrigation fluid inwardly over the end of the telescope to wash away any accumulated materials that might obstruct the surgeon&#39;s view through the telescope or interfere with illumination by the fiber optic light carrier. 
     The telescope has projections  31 , which cooperate with detents (not shown) in opening  24  to lock the telescope in place in the sheath  12 . Near the proximal end of sheath  12 , just below the fitting  22 , is a nut  26 , which is rotatable, but restrained against axial movement along the sheath. The nut is engageable with threads  28  on coupling  14 , allowing the sheath to be removed for replacement. The sheath can be rotated about its own axis in the coupling  14  and locked by nut  26  in any desired rotational position. Therefore, it is possible to orient a side-viewing telescope locked in the sheath to any desired angle in order to view a field to the side of the telescope axis. 
     Below the nut, as shown in FIGS. 1,  8  and  9 , a tapered element  30 , comprising upper and lower, axially spaced, frusto-conical parts  30   a  and  30   b,  is provided on the sheath. The tapered element mates in fluid-tight relationship with O-rings  31   a  and  31   b,  which serve as seals. The O-rings are located in annular recesses in a tapered hole  33  extending through the coupling  14 . Slots  32 , which are located on a narrow section of the sheath between parts  30   a  and  30   b,  provide fluid communication between the interior of sheath  12  and a fluid channel  35  extending through an adapter  34 , which is threaded into a wall of the coupling as shown in FIG.  8  and provided with an internally threaded collar  36 , used to secure coupling  14  to a selected one of threaded fittings  38  and  40  the lower end of the handle, as shown in FIG.  4 . The unused threaded fitting is closed by a cap  42 . As shown in FIG. 8, the adapter  34  is provided with a collar  44 , having a pair of projections  45 , engageable with a selected opposed pair of depressions formed in an end face of fitting  38 . Twelve such depressions  46  are shown in the end face of fitting  40  in FIG.  3 . (Fitting  38  has similar depressions.) The engagement of the projections with the depressions allows the coupling to be locked at any selected one of twelve discrete angles with respect to the axis of the handle  16 . In this embodiment, the angle of the telescope relative to the longitudinal axis of the handle is limited to twelve discrete angles. 
     The slots  32  of tapered element  30  are preferably located close to the proximal end of the tube  18  to maximize the length of the portion of tube that can be inserted into the nasal cavity without requiring an excessively long telescope. The fact that the coupling is located to the side of the handle allows the valves to be located within the handle rather than in an assembly aligned with the telescope axis. This, in turn, allows the use of a relatively short coupling, which also contributes to the maximization of the working length of the telescope. 
     The handle  16  is elongated and, as shown in FIGS. 6 and 7, preferably has a generally oval-shaped, symmetrical, cross-section transverse to its direction of elongation, so that the handle has flat, or nearly flat, wide faces  48  and  50 , and arcuate narrow faces  52  and  54 . The fittings  38  and  40  extend laterally in perpendicular relation to the axis of elongation of the handle and also perpendicular to the narrow faces of the handle. 
     As shown in FIG. 11, a manifold  56  is provided at the bottom of the handle. The manifold is provided with two openings, one being opening  58  in fitting  40 , the other being a corresponding opening in fitting  38 . These openings are of a size to receive, and closely fit, the projecting portion of adapter  34  (FIG.  8 ), so that the passage  35  in the adapter can communicate with the interior passage  60  of the manifold. The internal passage of the manifold is connected to irrigation and suction ports (not shown) of valves  62  and  64 . The valves  62  and  64  are operated respectively by push-buttons  66  and  68  at the top of the handle through internal push-rods  70  and  72 . Fitting  74 , on valve  62 , is connectible to a flexible, tubular irrigation fluid line  76  (FIG.  1 ), while fitting  78 , on valve  64 , is connectible to a flexible, tubular suction line  80 . The fittings  74  and  78  preferably extend in a direction transverse to a plane defined by the handle axis and the sheath axis so that the suction and irrigation lines extend from the instrument laterally off the operating table rather than toward the head or foot of the patient, and so that the instrument itself can be moved more easily. Optionally, the portions of the valves on which the fittings  74  and  78  are located can be made rotatable about axes parallel to the direction of elongation of the handle so that the suction and irrigation lines can be easily positioned on either side of the operating table. 
     The exterior surface of the handle preferably has gripping ribs  82  on both short sides and thumb-placement depressions  84  on the short sides near the upper end of the handle. 
     A hook  86 , molded as part of the handle, extends from the upper end of wide face  48  of the handle. As shown in FIGS. 1,  2 ,  3 ,  5 - 7  and  11 , the hook comprises a first part  86   a  extending laterally with respect to the direction of elongation of the handle and a second part  86   b  extending, from the laterally extending first part, alongside the handle in spaced relation to the handle. The hook is thus designed to rest on the surgeon&#39;s hand, normally just above the second metacarpal. 
     As shown in FIG. 4, because the coupling  14  is selectably attachable to either end of the manifold  56 , the instrument can be adapted for use by left or right-handed surgeons. Fluid-tight cap  42  closes the end of the manifold not connected to the coupling. 
     The ability of the coupling to be locked in any selected one of a plurality of discrete angles relative to the axis of the handle, and the rotatability of the telescope sheath about its own axis make it possible for the surgeon to adjust the irrigation/suction tube to the optimum angle for the surgeon&#39;s comfort and for the particular operation being performed. For typical nasal surgery, the coupling  14  will be disposed so that, when the sheath  12  is in the coupling, the axis of the sheath is at an angle of approximately 30 degrees relative to the long axis of the handle. However the angle may vary depending on the position of the patient and the particular surgery being performed. The adjustability of the angle allows the handle to be nearly vertical, i.e. in a neutral position, for optimum comfort to the surgeon. The irrigation and suction buttons  66  and  68  can be easily operated with the thumb without changing the surgeon&#39;s grasp on the handle. The hook allows the instrument to rest on the surgeon&#39;s hand to minimize fatigue. Moreover, the handle is positioned relative to the tube so that the instrument can be used while the surgeon&#39;s arms and/or hands are supported by suitable rests provided on the operating table rails. 
     The invention has other advantages, including the following. First, by eliminating the need for the surgeon to grasp the instrument, in the conventional manner, along the axis of the telescope, it provides increased space in front of the patient&#39;s nostril for the placement and manipulation of other instruments used in sinus surgery. Second, the instrument provides improved irrigation of the distal lens of the telescope, keeping it free of blood and surgical debris, and thereby significantly improving visualization, surgical efficiency and safety. Third, the instrument provides for irrigation of the surgical site for removal of blood and debris from the surgical site itself. Fourth, the instrument is more efficient in that it allows the surgeon to control irrigation by hand rather than by foot control. Fifth, the telescope can be attached to either side of the handle, and therefore the instrument can be used with equal facility by a left-handed or right-handed surgeon. Sixth, the instrument reduces surgeon fatigue because the angle of the telescope relative to the handle can be adjusted, allowing the telescope to be positioned in the patient&#39;s nostril at any desired angle, while the handle is held vertically or at another angle most comfortable for the surgeon. Finally, in the case of a side-viewing telescope, the rotatability of the sheath about its own axis also contributes to the reduction of fatigue, by avoiding the need to reposition the handle in order to adjust or change the field of view. 
     Various modifications can be made to the apparatus described. For example, the coupling can be positioned at the center of the manifold, midway between the narrow faces of the handle and perpendicular to wide face  50 . The instrument can, of course, be used in operations other than sinus surgery, and can be modified in various respects depending on its application. Thus other modifications may be made to the apparatus and method described above without departing from the scope of the invention as defined in the following claims.