Abstract:
Hand-held instruments have an actuator assembly which may be employed to actuate a distally mounted tool by application of radial force about the entirety of the instrument circumference (i.e., is omni-actuatable). Most preferably, the actuator assembly includes a plurality of circumferentially spaced-apart generally L-shaped actuator levers defining respective arcuate bearing surfaces along exterior edge regions thereof, and a retaining ring which circumferentially bounds the actuator levers around the exterior edge regions thereof. The retaining ring most preferably defines an interior stationary arcuate guide surface in conformable mated relationship to the bearing surfaces of said actuator levers. Radial force applied to the proximally extending arm sections of said levers thereby responsively causes the bearing surfaces thereof to be slideably moved along the guide surface of said retaining ring so as to translate such radial force into longitudinal movements of an elongate actuation pin between retracted and extended positions thereof. By providing a tool which operatively coacts with the actuation pin, a surgeon may actuate the tool as needed by applying radial force at any point about the circumference of the actuator assembly.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to hand-held instruments and tools. In preferred forms, the present invention relates to hand-held surgical instruments, especially those usefully employed for ophthalmic surgical procedures. 
     BACKGROUND AND SUMMARY OF THE INVENTION 
     Ophthalmic surgical procedures require the use of miniaturized instruments such as, for example, forceps, scissors and the like in order to allow the surgeon to operate on and within a patient&#39;s eye. One well known instrument that is used for such ophthalmic surgical procedures is the so-called Sutherland-type instrument commercially available from Alcon Grieshaber. The Sutherland-type instrument has a pen-like handle and uses a lever as an actuator for actuating mechanically operable spring-loaded tools, such as forceps, scissors, knives and the like which are threaded or otherwise operably connected to the distal end of the handle. 
     Recently, improvements to such Sutherland-type instruments have been proposed in U.S. Pat. No. 5,634,918 (the entire content of which is expressly incorporated hereinto by reference). In general, the improvements proposed by the &#39;918 Patent include providing a circumferentially arranged series of lever-like triggers which are pivotal in response to a radial force being applied thereto. Radially inward and outward pivotal movements of one trigger will, in turn, be converted respectively into rightward and leftward translation of the trigger retainer and is accompanied by like simultaneous movement of all the other triggers. Thus, any working tool attached operable to the trigger retainer will likewise translate rightward and leftward therewith. 
     Additional improvements in Sutherland-type instruments are disclosed in copending U.S. patent application Ser. No. 09/549,469 filed on Apr. 14, 2000, the entire content of which is expressly incorporated hereinto by reference, in which a radially flexible actuator band is seated in a generally V-shaped circumferential channel defined between a pair of rings, at least one of which is longitudinally moveable. In response to a radially compressive force. The actuator band will therefore be flexed radially inwardly so as to longitudinally move at least one of the slide rings, and hence a distally mounted tool operatively connected thereto. 
     The present invention is directed to further improvements in surgical instruments of the Sutherland-type. In this regard, the present invention broadly is directed to hand-held instruments which may be employed to actuate a distally mounted tool by application of radial force about the entirety of the instrument circumference (i.e., is omni-actuatable). In preferred forms, the present invention is embodied in hand-held instruments having a handle which includes an actuator assembly for actuating a tool, wherein the actuator assembly includes a plurality of circumferentially spaced-apart generally L-shaped actuator levers defining respective arcuate bearing surfaces along exterior edge regions thereof, and a retaining ring which circumferentially bounds the actuator levers around said exterior edge regions thereof. The retaining ring most preferably defines an interior stationary arcuate guide surface in conformable mated relationship to the bearing surfaces of said actuator levers. 
     In especially preferred embodiments, the actuation levers are one-piece structures which include a proximally extending manually actuable arm section, and a generally radially downwardly extending leg section. Bearing surfaces are defined along exterior edge regions of the levers at respective junctures between these arm and leg sections so as to cooperate with the conformably shaped guide surface of the retaining ring. 
     Most preferably the levers have proximally extending arm sections which are planar structural elements oriented coincidentally in respective radial planes emanating from the longitudinal axis of the device. These proximally extending arm sections thus define edge regions which establish generatrices of a curved surface (which may be convexly and/or concavely curved) in surrounding relationship to the device&#39;s longitudinal axis. 
     These as well as other aspects and advantages of the present invention will become more clear after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof. 
    
    
     BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
     Reference will hereinafter be made to the accompanying drawings, wherein like reference numerals throughout the various FIGURES denote like structural elements, and wherein 
     FIG. 1 is a perspective view of a hand-held surgical instrument in accordance with a presently preferred embodiment of the invention; 
     FIG. 2 is an enlarged perspective view of the actuator assembly employed in the surgical instrument of FIG. 1; 
     FIGS. 3 and 4 each depict a cross-sectional elevational view of the actuator assembly of the present invention in rest and operative conditions thereof, respectively; and 
     FIGS. 5A and 5B depict an alternative embodiments of the actuating levers that may be employed in the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Accompanying FIG. 1 depicts an exemplary embodiment of a hand-held surgical instrument  10  according to the present invention. In this regard, the surgical instrument  10  includes an elongated handle  12  sized and configured to allow the instrument  10  to be handled manually by a surgeon during surgical procedures. The handle  12  includes a manually operated actuator assembly  10 - 1  which serves to actuate a tool  11  operatively attached to, and extending from, the distal end of the handle. The tool  11 , for example, may be a miniature forceps  11 - 1  positioned at the distal-most end thereof which open and close in response to actuation of the actuator assembly  10 - 1  in a manner that will be described in greater detail below. 
     As is perhaps more clearly shown in accompanying FIG. 2, the distal end  12 - 1  of the handle  12  includes an axially elongate cylindrical recess  12 - 2  which receives a proximal correspondingly configured stem portion  14 - 1  of the actuation pin holder  14 . The stem portion  14 - 1  of the actuation pin holder  14  is most preferably fixed immovably within the recess  12 - 2  by any convenient technique, for example, by press-fitting and/or adhesives, so that the actuation pin holder  14  is a rigid distal extension of the handle  12 . 
     The distal end of the actuation pin holder  14  is provided with a circumferentially enlarged male head portion  14 - 3  which is threadably coupled to a threaded female recess portion  16 - 1  of the lever housing  16 , the purpose and function of which will be described in greater detail below. 
     The actuation pin holder  14  also defines a distally open-ended, axially oriented, cylindrical hollow  14 - 2  which is sized so as to movably receive therewithin the proximal barrel portion  18 - 1  of the actuation pin  18 . The barrel portion  18 - 1  is therefore capable of coaxially longitudinal sliding movements within the hollow  14 - 2  of the pin holder  14  so as to move axially between advanced and retracted conditions. In this regard, the structures are shown in accompanying FIG. 2 as being in their respective rest, or “normal” conditions. Thus, the “normal” condition for the actuation pin  18  is in its retracted condition as shown therein. 
     The distal end of the actuation pin  18  includes a generally conically shaped bearing nib  18 - 2  which distally projects from an axially transverse flange  18 - 3 . An annular channel  18 - 4  is defined between the transverse flange  18 - 3  and the proximally disposed barrel portion  18 - 1  and receives the terminal end regions of each of the circumferentially spaced-apart actuation levers (a few of which are identified in FIG. 2 by reference numeral  20 ). 
     As shown, each of the actuation levers  20  is generally L-shaped and includes a proximally extending arm section  20 - 1  of substantially greater length as compared to the distal leg section  20 - 2 . The levers  20  are most preferably one-piece structures and define an arcuately shaped bearing surface  20 - 3  along an outer edge region generally at the juncture of the arm and leg sections  20 - 1 ,  20 - 2 . 
     The housing  16  defines a plurality of radially oriented slots corresponding in number to the number of actuation levers  20 . The slots  16 - 2  are circumferentially spaced-apart from one another by an equal angular distance so that each receives therein a respective one of the actuation levers  20  generally at the juncture between the arm and leg sections  20 - 1  and  20 - 2 . The levers  20  are thus also circumferentially spaced apart from one another about the central longitudinal axis A l  (see FIG. 2) of the device  10  and thus the actuation pin  18  also. In such a manner, the arm sections  20 - 1  of each lever  20  extend proximally outwardly from the housing  16  and thus bridge the space between the housing  16  and the distal tapered end  12 - 3  of the handle  12  in coaxially circumferentially surrounding relationship to the actuation pin holder  14 . These numerous exposed arm sections  20 - 1  of each actuation lever  20  thereby present the attending surgeon with a tactile sensation of a seemingly “solid” surface surrounding the central longitudinal axis of the device  10 . Thus, the exposed proximally extending outer edge regions of the arm sections  20 - 1  will establish the generatrices of a curved surface which coaxially surrounds the longitudinal axis A l  of the device  10  and essentially bridges the distance between the distal lever housing  16  and the proximal handle  12 . 
     The actuation levers  20  are physically retained in each of their respective slots by an annular retaining ring  22  which bounds the housing  16  and the individual actuation levers  20  disposed in the slots  16 - 2 . The retaining ring  22  defines an interior cross-sectionally arcuate stationary guide surface  22 - 1  which conformably mates with the bearing surface  20 - 3  of each of the actuation levers  20 . Thus, the radii of curvature of each of the surfaces  22 - 1  and  20 - 3  are coincident with one another. 
     As will be observed particularly in FIGS. 1 and 2, the individual actuation levers  20  are most preferably relatively thin, planar structures which are oriented in the radial slots  16 - 2  of the housing  16  so as to be disposed coincident with radial planes from the central axis A l . The exposed outer proximal edge regions of each of the levers  20  may thus be provided with serrations  20 - 4  so as to promote a more rough feel to the attending surgeon. Other means may also be employed in order to improve the tactile sensation and/or feel of the levers  20 , such as, for example coating at least the external exposed edges of the levers with a friction material (e.g., an elastomeric material) or the like. 
     The operation of the actuator assembly  10 - 1  employed in the hand-held surgical device  10  in accordance with the present invention is depicted generally in accompanying FIGS. 3 and 4. In this regard, the proximal end  11 - 2  of the tool  11  (see FIG. 1) may be threadably and removeably connected to the threaded nipple  16 - 3  coaxially extending distally from the housing  16 . Although not shown, the tool  11  will conventionally have an actuator rod which extends through the nipple  16 - 3  proximally into operative engagement with the bearing nib  18 - 2 . Moreover, the tool  11  is conventionally provided with a spring element which urges the actuation rod thereof into contact with the activation nib  18 - 2 . Thus, the force of the tool&#39;s spring element will cause the actuation pin  18  to be displaced proximally within the holder  14  so that it assumes its “normal” or rest condition as shown in FIG.  3 . 
     Upon application of a radially inwardly directed force (as noted by the arrows A f  in FIG.  3 ), the lever arms  20 - 1  are caused to move collectively toward the holder  14  (that is, to be moved to a position closer to the central axis A l  of the device  10 ). More specifically, the bearing surfaces  20 - 3  of the levers  20  are caused to slide along the cross-sectionally arcuate guide surface  22 - 1  of the retainer ring  22  so that as to cause the radially inwardly directed lever leg  20 - 2  to be moved generally pivotally from its rest condition as shown in FIG. 3 to its active condition as shown in FIG.  4 . As will be observed, since the terminal ends of each of the legs  20 - 2  are received within the annular channel  18 - 4  of the actuation pin  18 , such movement (or “throw”) of the lever legs  20 - 2  will translate in coaxial linear movement of the actuator pin  18  (and hence its distally extending actuation nib  18 - 2 ) from its rest position as shown in FIG. 3 to its actuation condition in the direction of arrow A m  as shown in FIG.  4 . Thus, the nib  18 - 2  will push the tool&#39;s actuation rod (not shown) distally against the bias force of the tool&#39;s spring element (also not shown) to cause actuation of the working elements of the tool  11 , such as the miniature forceps  11 - 1  as depicted in FIG.  1 . 
     It should be noted here that, although the tool  11  is in and or itself conventional and of the type that may be employed generally in combination with Sutherland-type instruments—that is, will have its own self-contained spring element—the surgical devices  10  in accordance with this invention could alternatively (or additionally) be provided with a spring element. For example, a spring element could be positioned within the hollow  14 - 2  of the holder  14  and exert an appropriate bias force on the actuation pin  18  as may be required or desired. 
     Accompanying FIGS. 5A and 5B depict alternative embodiments of the actuator assembly  10 - 1  that may be employed in the devices of the present invention. In this regard, each of the actuator assemblies  10 - 1 ′ and  10 - 1 ″ shown in FIGS. 5A and 5B, respectively, is generally identical to the actuator assembly  10 - 1 , with the principal exceptions being the configurations of the levers  20  and the retaining ring  22 . Thus, identical structural elements among the various embodiments are noted by the same reference numerals. 
     By way of example, the embodiment depicted in FIG. 5A includes actuation levers  20 ′ which define a generally semi-circular bearing surface  20 - 3 ′ provided generally at the juncture between the proximally extending lever arm sections  20 - 1 ′ and the downwardly radially projecting leg sections  20 - 2 ′. This bearing surface  20 - 3 ′ therefore bears against, and cooperates with, a semi-circularly shaped guide surface  22 - 1 ′ defined in cross-section by the retaining ring  22 ′. A retaining lip  20 - 5  is also provided as an extension of sorts of the bearing surface  20 - 3 ′ and therefore projects somewhat distally around the guide surface  22 - 1 ′ so as to assist in the sliding movement of the bearing surface  20 - 3 ′ against the stationary guide surface  22 - 1 ′. 
     The terminal ends of the lever leg sections  20 - 2 ′ terminate in a slightly arcuate terminal edge  20 - 4 ′ which is received within the recessed channel  18 - 4  of the actuation pin  18 . The center of the arcuate terminal edge  20 - 4 ′ is coincident with centers of the semi-circular bearing surface  20 - 3 ′ and guide surface  22 - 1 ′, capturing the levers  20 ′ between them. The arcuate edges  20 - 4 ′ of the leg sections  20 - 2 ′ thereby help to ensure relatively smooth pivoting of the levers  20 - 1 ′ around the coincident centers of the arcs defined by the surfaces  20 - 3 ′,  22 - 1 ′ and  20 - 4 ′ and thus relatively smooth movements of the actuation pin  18 . The coincident centers of the arcs defined by surfaces  20 - 3 ′,  22 - 1 ′ and  20 - 4 ′ may lie outside the major diameter of the handle. 
     It will also be observed that the leg sections  20 - 2 ′ project downwardly and somewhat proximally as compared to the leg sections  20 - 2  discussed previously. Thus, instead of the arm and leg sections  20 - 1  and  20 - 2 , respectively forming a substantially right (or minimally obtuse) angle therebetween, the arm and leg sections  20 - 1 ′ and  20 ′- 2 ′ form a somewhat acute angle therebetween. 
     The levers  20 ″ shown in FIG. 5B are substantially identical to the levers  20 ′ shown in FIG. 5A except for the curvature of the arm sections  20 - 1 ″ thereof. In this regard, it will be observed that, whereas the proximally extending arm sections  20 - 1 ′ of the levers  20 ′ shown in FIG. 5A have a slight convex curvature, the arm sections  20 - 1 ″ have a slight concave curvature. Of course, the levers that may be employed in the practice of this invention may have virtually any geometric configuration and/or curvature combination (including levers having respective sections of convex and concave curvatures) as may be desired by an individual physician&#39;s personal preference. Thus, for example, instead of having any curvature (concave and/or convex), the levers may define a linear edge which is substantially parallel or even somewhat angularly disposed relative to the longitudinal axis A l . 
     While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.