CA2181921A1

CA2181921A1 - Endoscopic microsurgical instruments and methods

Info

Publication number: CA2181921A1
Application number: CA002181921A
Authority: CA
Inventors: Alex T. Roth; Scott H. Miller
Original assignee: Individual
Current assignee: Heartport Inc
Priority date: 1994-02-14
Filing date: 1995-02-09
Publication date: 1995-08-17
Also published as: JPH10500583A; JP3524101B2; WO1995021573A1; EP1348381A3; ATE264656T1; EP0744918A4; AU686746B2; EP1348381A2; AU1747795A; US5501698A; DE69532918T2; EP0744918B1; DE69532918D1; US5810877A; US5618306A; ES2217276T3; EP0744918A1

Abstract

The invention provides devices and method for performing extremely small-scale, minimally-invasive microsurgery. The instruments of the invention utilize a symmetrical, forceps-like actuator (28) which provides extremely precise actuation and control of the instrument and which mimics the feel of the instruments used in conventional open surgical procedures. The instruments general include a pair of coaxially arranged shafts (22, 46), an end effector (40) at the distal ends of the shafts (22, 46), and an actuator (28) at the proximal end of the shafts (22, 46). The actuator (28) includes a pair of arms (36) pivotally coupled to one of either the outer or inner shaft, and a pair of links (52) pivotally coupled at one end to the arms (36), and at a second end to the other of the shafts. The actuator (28) may be easily adapted for either pull-type or push-type actuation, and for either outer shaft (22) or inner shaft (46) translation. The end effectors (40) may have a variety of configurations, including needle drivers, forceps, scissors, and clip appliers.

Description

WO 95121573 21~ 1 9 21 r~ cil~O~
, ;l C MTcRosm1aTr~T~ MF!'I'UOI-C
FIELD OF TllE: ~h~n.11 5 This invention relates generally to in~LL Ls for performing m;n;r=l ly-invasive surgery, and more specifically, to in~,LL, ~s for performing exLL -ly 6mall-scale, min;r-l ly-invasive mi~;LuYUL~elies such as coronary artery bypass grafting.
P~ ~~ ~~ ~ OP T~E ~h ~r ~n _ M;n;r-11 y-invasive surgical tenhn; qllPR, such as thoracoscopy, laparoscopy, pelviscopy, Pn~lnscory, and aLUlLoscu~y, m;n;m;7P patient trauma by prûvsding access to interior body cavities through very small ;n~-;Rinn~ or through r~ n~JuR c~nmllA~ known as trocar sleeves. To perf~rm a surgical yLùc~duLe, elongated, low-pro$ile ir. ,LL, ts are introduced into a body cavity through these ; n~ ; n~ or trocar sleeves. ViF-~Al;-7ation is facilitated by percutaneous v;~ tion devices known as lapaLuscu~es, ~ s~u~P~, aL Ullu~..ul,es, and the like, which typically consist of a video camera configured for inLLuluuLion through a small ;n~ ;nn or trocar sleeve to allow observation of the body cavity on a video monitor. By obviating the need $or a large, open incision to expose the body cavity, m;n;r~ ly-invasive techniques can significantly reduce the pain, rcJuv~:Ly period, morbidity and mortality rates, and cost of open surgical P~OCL-1Ura6 without a sacrifice in efficacy.
In recent years, m;n;r~~lly-invasive techniques have been developed to facilitate the performance of a variety of surgical PIUC~dUL~5 on organs and ducts of the Ah~l ;n:~ll and pelvic cavities . Well-known examples of such p Luce luL ~8 include laparoscopic cholecystectomy, laparoscopic ArpPnrl~ctomy, lapaIùscupic hysterectomy, and laparoscopic hernia repair.
A particularly important milestone in m;n;r-l ly-inva8ive surgery has been attained with the development o$ thoracoscopic techniques for surgery of the SUBSTITUTE SH~ (RUI~E26) , .. ... ... . .. . .

W0 95~21573 ~ E~ oo~
~181921 2 heart and great vessels. Such t~chniques are described in co-pending, commonly-as6igned U. 5 . patent application Serial No. 08/023,778, filed February 22, 1993, the complete disclosure of which i8 hereby incorporated herein by reference. In that application, thoracoscopic techniques for performing coronary artery bypass grafting (CABG) are described which eliminate the need for the sternotomy or other form of gross thoracotomy required by conv~ntinn~l, open surgical techniques. In thoracoscopic CA~3G, an arterial blood source such as the internal mammary artery (INA) is dissected from its native location, tr;~ncert~cl, and },Lt~ ed for attachment to an anastomosis site on a target coronary artery, commonly the left anterior clDqr~n~l;n~ coronary artery (L~D). A portion of the target coronary artery containing the anastomosis site is then dissected away from the epicardium, and a small i nc; 5; nn is made in the arterial wall. The distal end of the arterial blood source (e.g. IMA) i8 then ana5~ cl over the incision in the target CULVI~ULY artery, usually by suturing. Each of the6e steps is performed by means of inDLL t.~ LLoduced through small inr;~innq or trocar sleeves positioned within intercostal spaces of the rib cage, under v; r ~l; 7-tion by means of an ~n~lnscnre or other percutaneous v; qll~l; 7~tion device.
Because the CABG ~Luc~duL~ requires complex mi~:Lunu~ye:Ly to be carried out on ~:~CLL~ 1Y small body ~LLuuLuL~a8, surgical ir.nLL, Ls designed for laparoscopic and other m;n;r-l ly-invagive applications are not generally suitable for performing thoracoscopic CA;3G. Most laparoscopic ~LUCedUL~a6;
for example, target body structures which are quite large in comparison to the coronary vessels, and do not require the high degree of precision required by mi~:Lu:~uLy~LieS such as CABG. Accordingly, lupaloscu~ic innLL, ~s generally have relatively large end-effectors with relatively large ranges of ~l , making such inn~L, Ls ill-suited for use on very small ~LLuuLuLc s like the coronary vessels. In addition, such innLL, -nts commonly have finger loops or pistol-type actuators gripped in the user ' 8 palm or between the user ' 8 thumb and forefinger, limiting the sensitivity and precision SUBSrlTUTE SHEEr (RU~E 26) Wo 95/21573 ~ 9 2 1 P~ c lOô5 with which such inoLLl L6 can be manipulated and actuated.
Such ~inger loops or pistol-type grips also are limited to a single orientation in the user ' s hand and cannot be repositioned in the hand to allow better access to a body structure or to change the orientation of the end-effector.
The advent of thoracoscopic CABG and other m;n;r-l ly-invasive microsurgical pLoceduLes therefore demands a new generation of microsurgical inOLL t,i specifically designed to meet the unique needs of such ~LO~ dUL~aS. Thege illoLL~ must have a small profile for introduction through small ;nr;cifnR or trocar sleeves, and a length sufficient to reach the heart and other thoracic organs and vessels from various percutaneous access points. The inaLL Ls must have end-effectors adapted to perform delicate, high-precision mi-;LO:~uL~r~ on very small vessels, ;nrll-A;n~ end-effectors having very small d; - - i onC and very short ranges of motion.
The inOLL Ls must have actuators that facilitate eLy~ i C, one-handed actuation with sensitivity and precision, preferably having a stroke which is large enough for comfortable actuation by the fingers and which is reduced to a very short range of motion at the end-effector. Desirably, the actuators will have a configuration which is analogous to surgical forceps or to other types of microsurgical irlqLL, ts commonly utilized in open surgical yLoce~
shortening the l~rn;n~ curve required for adoption of m;n;~ql ly-invasive microsurgical terhn;qlloc.
8~JIQIARY OP T~l~ lh~
This invention provides in,,LLI ts and methods to facilitate the performance of minir-11y-invasive micro~urgical c~-luLe:s, and particularly, the performance of thoracoscopic CABG and other ~ceduLI s on the heart and great vessels. The inOLL, Ls of the invention facilitate a variety of surgical activities, including application of clips or staples, suturing, incision, trAnoection, dissection, retraction, and r~n;rl~lAtion, and are specially adapted for use on exLLI eJy small body ~iLLUl.:~UL~S such as the coronary blood vessels. To allow precise mi~ L~oUL~I=Ly to be performed on a very small SUBS~ITUTE SHEET tRU~ E 26) WO 95121573 ~ r~ OO~
acale, the in,.~r L~ are adapted to be held in a single hand in a manner analogous to surgical forceps. The in~.LL ~nts are actuated by a pair of symmetrical, proximally-hinged, forcep-like arms which can be pivoted by the fingers for sensitive and precise actuation of an end-effector. The ,,y ~ of actuation allows each instrument to be rotated or otherwise repositioned within the user ' 5 hand to change the orientation of the end-effector without ~ ;ng the ease of actuation. Noreover, the actuator's proximal hinge, along with a proximally-disposed linkage ~- ` An;F-, allow the distance between the user ' s hand and the body surface to be ~;n;m;7g~1 for optimal control of the i~ Ll -nt.
In a preferred: '- ; L, a microsurgical inc.LL, L
according to the invention comprises an outer shaft having an axial lumen, and an inner shaft slidably fl;~:ros~d in the axial lumen. An end-effector is coupled to the distal end of the inner shaft and is movable relative to the outer shaft. An actuator is fl; ~ros~cl at the proximal end of the outer shaft for actuating the end-effector. The actuator ;nr~ fl~ first and second arms each coupled at its proximal end to one of either the outer shaft or the inner shaft, each arm extending distally and biased outwardly so as to form an acute angle with the outer shaft. A link is coupled to each arm and to the shaft to which the arms themselves are not coupled. In this way, the first and second arms are symmetrically pivotable so as to pivot the links, thereby translating the inner shaft relatiYe to the outer shaft to actuate the end-ef f ector .
The end-ef f ector of the in.. LL I L may have a variety o~
configurations for performing a variety of functions. The end-effector may compri6e a pair of jaws which may be adapted for various ~ LI.oses, including cutting, grasping, holding a suture needle, and applying a clip or staple. In an exemplary tt, the end-effector comprises a first jaw fixed to the outer shaft, and a second jaw coupled to the inner shaft, such that translating the inner shaft relative to the outer shaft moves the second jaw relative to the first jaw. The second jaw may be pivotable, axially slidable, rotatable, or SUBSrITUTE SHEEr (RU~ E 26~

2 1 819 21 ~ PCT/US9~/01885 deflect:~hl~ relative to the first jaw. The jaws may be configured to have opposing gripping surfaces for grasping tissue or holding a suture needle, or may have sharp cutting edges movable in a shearing relationship relative to each other for cutting tissue. The jaws may further be ~l;Cp~5~d at various angles and orientations relative to the inner and outer shafts to provide a range of end-effector configurations to meet a variety of surgical needs.
Alternatively, the end-effector may be adapted for applying a clip or staple to a body structure. In an eYemplary configuration, the end-effector ;nr31~ s a pair of jaws fixed to the distal end of the inner shaft and adapted to hold a clip or staple between them. The jaws are biased away from each other and are deflectable toward one another. Upon actuation, the outer shaft is configured to slide distally over a proximal portion of the jaws so A5 to urge the jaws toward one another, thereby closing the clip or staple.
Preferably, the in-,~L, c of the invention are adapted for e~LL~ -ly small scale microsurgical ~roce-luLes such as c.,Luna~2~ anastomosis. To facilitate such ~l~n,eduL~:s, the arms of the actuator are configured to provide a comfortable range of motion for forcep-like finger actuation, a range of motion which is reduced to a very small range of motion at the end-effector, thereby providing sensitive and precise actuation for very small end-effector - ~ Ls.
In actuating very small end-effectors through very small ranges of motion, the m;n;m;oation of friction is important in providing smooth and preci6e actuation. To reduce friction, the links are coupled to the shaft (either inner or outer) such that the transverse force exerted on the shaft by one link is opposed by a ~LC~ VeL:~e force eYerted on the shaft by the other link. Usually, this is accomplished by coupling the inner ends of the links to the shaft at points which are eguidistant from the proYimal end of the shaft. In this way, as the arms are pivoted inwardly, the links do not urge the inner shaft against the outer shaft (or viCê versa), which would produce friction as the shafts move relative to each other .
SUBSTITUT~ SHEET (Rlll E 26) .

W095121573 ~ 9?~1 r~l io~
The arms may be ben~lAhle or rigid, and the arms may be coupled to the inner or outer shaft in various ways, including by pins, by living hinges, by bar linkages, or by other means.
Preferably, however, the arms are hinged at their proximal ends to the inner or outer shaft. A means for biasing the arms outward is provided, which in one ~ comprises a flat spring coupled to each arm. With a hinge elLLCIII, L, the arms may be rigid, rather than being ben~hl e or resilient, permitting a wide variety of materials and geometries to be used. In this way, the arms may be designed for optimum performance and minimum cost.
The links may be conf igured 80 as to translate the inner shaft either distally or proximally relative to the outer shaft as the arms are pivoted inwardly. To provide translation of the inner shaft proximally, the inner ends of the links are rli ~:posed proximal to the outer ends of the links. To provide translation of the inner shaft distally, the inner ends of the links are ~ rnC~d distal to the outer ends of the links.
The in-.LL, Ls of the invention are further advantageous in that they allow the user to hold and actuate the ir..,LL L
from a position which is as close as possible to the surface of the patient's body, optimizing control of the in~LL, L.
The proximally-hinged arms permit the user to engage the arms near their distal ends, and to i--LLuduce the in-.LL, L into the patient's body cavity through an ;n-;R;on or trocar sleeve up to the distal ends of the arms. In this way, the user may engage and ~n;r1~lAte the in~L L in a position immediately adjacent the surface of the patient's body. The links are preferably coupled to the arms in a proximal portion thereof 80 as not to interfere with or limit ir~LLudu. Lion of the in:.LL~ L. Proximal disposition of the links also r~Y;m;7eq the r- ~n;cAl advantage obtained from the forces exerted on the distal ends of the arms, and allows the stroke of the arms to be amplified relative to the range of motion of the end-ef f ector .
The invention may further include means for locking the arms in a closed position. This may be useful to ensure the SUBSTITUTE SHEEr (RULE26) WO 95121573 2 i 8 i 9 ~ i Pcl/uS95/0188 jaws of the end-effector are closed for i11LL~,.Iu~ Lion or removal from the body cavity, or to reduce the risk of inadvertent injury to the patient caused by an open end-ef f ector .
Usually, the in_-L, ~s of the invention are adapted for cn(4~scoric uses, wherein the end-effector is introduced through a small incision or trocar sleeve into the body cavity. To facilitate such iJ.LL~,.Iu..~ion, the profile of the end-effector and outer shaft are preferably minimized. In one . ~ L, the outer shaft has a diameter of less than about 5 mm.
The inD~L, Ls of the invention may be utilized to perform a variety of surgical ~r~ce,luL_.,, both conVPnt;on;ll, open p~oce,luL eS and m; n; r- l l y-invasive ~L o~e-l,,L eS . In an ~ ; c method of LL ea L according to the invention, the distal end of the ir-,LL is i"L~o-l-ced through a ptL~.uLc-i.e~6 pel.eLLlltion into a body cavity, and, under vi ~ tion by means of a scope introduced through a peL~;uL~ Ous peneLL~ion, a distal portion of at least one arm is pressed inwardly to symmetrically pivot both arms toward the shaft, thereby closing the jaws of the end-effector on a body structure in the body cavity . In various ~mhor7 i s, the method may be used for cutting, dissecting, transecting, retracting, or otherwise r~n; r~ ting a body ~Lu ~uLe, as well as for suturing, or for applying clips or staples to a body ~LL~IeLure. In a particularly preferred `~ , the method is utilized in a thoracoscopic CABG ~Loced~LJ for dissecting a graft vessel such as the IMA from its native location, and performing an anastomosis of the graft vessel to 3 0 a coronary artery such as the I,AD .
A further understanding of the nature and advantages of the invention may be realized by reference to the ~ ;n;n~
portions of the specification and the drawings.
3 5 BRIE~ D~ OF T~E DRAWING8 Figure lA-lB are side and top elevational views, respectively, of a microsurgical in~L,, -rL constructed in accordance with the principles of the invention.
SUBSTITUTE SHEEr (RULE26) ... ...

W0 95121573 2 ~ 8 ~ L J~ . S'~IOO~.
Figure 1C is an illustration of a patient ' 8 chest in partial section illustrating the use of the inDLL, L of Figures lA-lB through a trocar sleeve.
Figures 2A-2B are side and top cross-sectional views, respectively, of a first e-~Qtlir of an actuator in the microsurgical inDLL, L of Figure 1.
Figure 2C i5 a side cross-sectional view of the actuator of Figure 2A in a closed position.
Figures 3A-3B are side and top cross-sectional views, respectively, of a second I ` ';r L of an actuator in the microsurgical inD-L, L of Figure 1.
Figure 3C is a side ~:L~58 se~ 1 ion~l view of the actuator of Figure 3A in a closed position.
Figures 4A-4B are side partial ~;LOSS 5~ ~ ionAl views of an actuator in the microsurgical illD~LI L of Figure 1 showing two alternative ' ' i Ls of an actuator locking nir~n.
Figures 5-6 are side, partial cross-section~l views of two alternative ~ c of an end-effector in the microsurgical inDLL, L of Figure 1.
Figure 7A is a side partial ~;Loss-section of an alternative t~mhorli- L of an end-effector in the microsurgical irlD LL ~ L of Figure 1.
Figures 7B-10 are side elevational views of various : i Ls of an end-effector in the microsurgical inDLL L
of Figure 1.
Figure 11 is a side, partial ~LOcD-s~- ~lon~l view of a further ~ 'i L of a microsurgical inDLL, L constructed in acc~ L~ with the principles of the invention.
3 0 Figure 12 is a cide elevational view of a distal portion of the microsurgical inDLL, L of Figure 11 illustrating the application of a surgical clip to a vessel.
Figure 13 is a transverse l l~ss-section taken through a patient' 8 thorax inferior to the heart showing the positioning of trocar sleeves and microsurgical in~LL, c according to the method of the invention.
SUBSTITUTE SHEEr (RU~ E 26) wo ~5121S73 2 1 8 1 9 2 1 P 1/~) loo.~
Figure6 14-15 and 17 are anterior elevational view6 of a patient's heart, illustrating the performance of a coronary artery anastomo6is according to the method of the invention.
Figure6 16A-16E illustrate a method of 6uturing a graft ve66el to a ~_VLUII~Ly artery according to the method of the invention .
DR~I~l T Rn DE8CRIPTION OF SPECIFIC
The in--L, L6 and method6 of the invention facilitate the performance of microsurgical ~,ucedu,æ6 with high preci6ion and control. The invention i6 therefore u6eful in any procedure where very 6mall body Etructure6 are involved or where highly-preciEe, very 6mall-Ecale 6urgical maneuver6 are being p~LL~ ', whether conventional, open procedures or m;nir-l ly-inva6ive pLU'`~dULt:S. Because, the in--LL LL and method6 are well-adapted for the performance of 6urgery through 6mall, percutaneou6 ;n~ici~nc or trocar 61eeve6, the invention i6 particularly well-suited for the performance of m;nir-l ly-inva6ive ,u,uc~du,a6 6uch a6 thoracoscopy, laparo6copy, and pelvi6copy. In a particularly preferred L, for example, the in,,LL t6 and method6 of the invention are utilized for the performance of thoraco6copic CA}3G procedures, wherein sp~ri~ ed in~, t~ are introduced through percutaneou6 penetration6 and/ or trocar 61eeves to di66ect a graft ves6el 6uch a6 the IMA from it6 native location, inci6e a cu~ a,y artery 6uch a6 the LAD
-DLLe~ of an arterial le6ion, and ana6tomo6e the graft ve6Eel to the c uLu~laLy artery. No known thoraco6copic, l~parù:;cu~ic, or other min;r-lly-inva6ive 6urgical in-LL~ c are 6uitable for performing the ultra-preci6e mi~:LU~UL~Ly required in a thuL~_06c.,uic CABG ~ruce-lu,e.
A fir6t preferred: ~~-;r L of a micro6urgical in~L,, L according to the invention i6 illu6trated in Figures lA-lC. Micro6urgical in~LL, L 20 include6 an outer 6haft 22 having a proximal end 24 and a di6tal end 26.
Proximal end 24 of outer 6haft 22 i6 mounted to an actuator 28. Actuator 28 ;n~ c a body 30 having a di6tal end 32 to which outer 6haft 22 iE mounted, and a proximal end 34 to SUBSTITUTE SHEET (RU~ E 26) . , .

Wo 95/21573 ~! 1 8 1 9 2 1 ~ io6J
which a pair of arms 36 are pivotally coupled. Arms 36 each have a proximal end 35 coupled to body 30, and a distal end 37 which is biased outwardly from outer shaft 22 to form an acute angle therewith. A finger grip 38 i5 ~ pnP:-~A near the distal end 37 of each arm 36, the finger grips comprising a plurality of grooves or other textural features to facilitate gripping and actuating the inDLL, .
As shown in Figure lC, actuator 28 is configured to be held between the thumb T and index f inger F of the u6er ' 8 hand, similar to the manner in which conv~-ntinnAl forceps are held. Arms 36 may be engaged on finger grips 38 by the tips of finger F and thumb T, with the proximal ends 35 of arms 36 resting on the user's hand between and/or behind index finger F and thum~ T. Held in this way, inDLL 20 is positinn~hl~ with high precision and control, and may be actuated with great ease by exerting inward ~L eSDUL è on f inger grips 38. In an exemplary c.mho~i ~, arms 36 are 8 to 12 cm.
in length, and form an angle a between 3' and 30, preferably between 5- and 10-, with outer shaft 22 in the open position.
Returning to Figures lA -lB, an end-effector 40 is mounted to the distal end of outer shaft 22. End-effector 40 may have various configurations according to the function which inDLLI ~ 20 is adapted to perform. In the ~mho~ L
illustrated, end-effector 40 is adapted for holding a suture needle, and in~ c a fixed jaw 42 mounted to outer shaft 22, and a movable jaw 44 pivotally mounted to outer shaft 22 and coupled to actuator 28 by means of an inner shaft 46, described more fully below. By pivoting arms 36 inward toward outer shaft 22, movable jaw 44 may be pivoted toward fixed jaw 42 in order to clamp a suture needle N therebeL~ as in Figure lC.
Outer shaft 22 and end-effector 40 are preferably configured for ~n~lnscopic uses, and have a profile suitable for illLL~ ion through a small p~=L~ uLal.eous incision or trocar sleeve TS into a body cavity BC, as illustrated in Figure lC. Ideally, the profile (cross-s~ctinnAl area) of outer shaft 22 is minimi 79d to provide maximum clearance through an incision or trocar sleeve, thereby maximizing the SUBSTITUTE SHEET (RU~ E 26) WO 95121S73 ~ l 8 l 9 21 PCTIUS95/0188~

maneuverability of the ir.~LL - ~. However, for most ~JLO~e-lULè5, outer shaft 22 must have significant rigidity to resist bending or b~-kl in~. For ~n~nsr opic applications, outer shaft 22 must also have a length sufficient to reach a - 5 target site within a body cavity from a position outside of the body . In an exemplary ~ L suitable f or thoracoscopic surgery on the heart, outer shaft 22 is constructed of a metal such as aluminum, titanium or stainless steel, has a round cross-section with a diameter of 2 to 10 mm, preferably about 3 to 5 mm, and has a length of about 10 to 30 cm., preferably about 20 to 25 cm.
The inDLL, tD of the invention may be configured for either pull-type or push-type actuation of end-effector 40.
An exemplary: '-'ir ~ of a pull-type actuator 28 is illustrated in Figures 2A-2C. Outer shaft 22 is fixed to a sleeve 45 retained within an axial bore 47 in body 30. A
SeL~L~_.. 49 engages sleeve 45 and permits axial adju,.i L of outer 6haft 22 relative to body 30. Arms 36 are hinged to body 30 by pins 48. Means are provided for biasing arms 36 outwardly, which may comprise a flat spring 50 at the proximal end 34 of body 30 shaped so that each end of spring 50 is l;aposed between an arm 36 and body 30. Flat spring 50 may be a resilient, flexible metal such as stainless steel.
Various alternative means may be used f or coupling arms 36 to body 30, such as a living hinge or bar linkage.
Alternatively, arms 3 6 may be f ixed to body 3 0 and/ or to each other, and provided with sl~ffic-i~nt flexibility to allow distal ends 37 to be deflected toward outer shaft 22. The hinge pin arrangement illustrated provides a simple and ls~p~r~ble co7-rl in~ with the advantage that arms 36 need not be flexible, allowing a wide variety of rigid materials to be used for the arms, including metals and plastics.
A pair of links 52 each have an outer end 54 pinned to an arm 36 and an inner end 56 pinned to a cylindrical clevis 58.
Outer ends 54 are coupled to arm 36 by pins 55 and h~ h;n~a 57 . Body 30 has an Il~JeL LUL" 60 in which inner ends 56 of links 52 ~re attached to proximal end 62 of clevis 58.
Proximal end 62 of clevis 58 is bifurcated by a channel 64 in SUBSTITUTE SHEET (RUl~E26) .. . .

W /t PCrlUS95/01885 095 1573 2~L8192~ -, 12 which inner ends 56 of links 52 are coupled by a pin 65.
Clevis 58 is ~ 7i7hl~Q within axial bore 47 in body 30. A
threaded hole 68 extends axially through a distal portion of clevis 58. A screw 70 is fixed to a proximal end 72 of inner shaft 46 and is threaded into hole 68, such that inner shaft 46 moves in tandem with clevis 58.
In operation, when arms 36 are pivoted toward outer shaft 22, lin7c6 52 pull clevis 58 and inner shaft 46 proximally relative to outer shaft 22, to the position shown in Figure 2C. ~Ql e~:ing inward force on arms 36 allows them to return to their outward position under the force of spring 50. The outward travel of arms 36 ig limited by the Pn~ of screw 70 and/or clevis 58 against the proximal end of sleeve 45. The eYtent of outward travel of arms 36, and hence the axial translation of inner shaft 46, may be adjusted by loo~Qnin~ St:L8~:L.~J 49 and axially repositloning sleeve 45.
Outer ends 54 of links 52 may be coupled to arms 3 6 at various positions between their proximal ends 35 and distal ends 37. In a preferred . '; ~, however, outer ends 54 are coupled to arms 36 in a proximal portion thereof, preferably at a point more than half tle length of arm 36 from its distal eDd 37 or from finger grip 38. By r-Yim; 7in~ the distance between the point at which the user presses on arms 36 and the point of col7rl ;ng to lin7cs 52, - ` ~n;~- 71 advantage is r~Y;m; 7Qr7. At the same time, this proximal positioning of the links leaves open the majority of the area between the distal portion of arms 36 and outer shaft 22, eliminating any pr~cc:;hi1;ty 0~ interference ~7etween lin,cs 52 and the patient's body, trocar sleeves, the user, or ot7.1er objects. This is particularly useful when the i_lD~LI ~:i are introduced into the patient ' s body through small incisions or trocar sleeves in laparoscopic, thoracoscopic, or other m;n;--lly-invasive surgical pLoc~.lu.~s. As shown in Figure lC, the il- ~" ~ ~s of the invention may be i..~L~-lu~ ed through such small access ports into the body cavity to the maximum extent (up to distal ends 37 of arms 36), such that the distance between the user's hand U and the patient's body P is m;n;m;~Q-7. Such SUBSTI I Z iT~ SHEE~ (RlJLE 26) Wo 95/21573 21819 2 ~ PCTiUS95/0188~

positioning facilitates maxim~m control of the inDLL, -t for ultra-precise r- n i rll 1 s7 tion .
Figures 3A-3C illustrate a pu6h-type r7nho~;r~ of actuator 28 in which inner shaft 46 is configured to be - 5 translated distally rather than proximally relative to outer shaft 22 when arms 36 are pivoted inward. The embodiment of - Figures 3A-3C is in many I~_~e. Ls similar to that of Figures 2A-2C, except that inner ends 56 of links 52, coupled to proximal end 62 of clevis 58, are ~ ro2~ distal to outer ends 54, coupled to arms 36. In this way, when arms 36 are pivoted inward, links 52 push clevis 58 and inner shaft 46 distally. To limit the outward travel of arm6 36, as well as the proximal r ~ L of in er shaft 46, a limit screw 74 is o~ed in a t_readed hole 76 in a proximal end of body 30.
Links 52 each have an eYtension 78 on a proYimal side thereof configured to engage a distal end 80 of limit screw 74 when arms 36 are in an outward position. The degree of outward travel of arms 36, as well as the axial translation of inner shaft 46, may be adjusted by rh;7n~ing the depth of limit screw 74 within hole 76.
Referring now to Figures 4A-4B, actuator 28 may further include locking means 86 for maintaining arms 36 in an inward position when ~1~3_.~L~: is released therefrom. Locking means 86 may have various configurations, inrll7r'ing the single-position design of Figure 4A, and the ratcheted design of Figure 4B. In t~e ~ - L of Figure 4A, locking means 86 comprises a catch 88 attached to each of ar~s 36 near the distal end 37 thereof. At least a first catch 88A is attached to arm 36 by a resilient, deflectable beam 90, allowing catch 88A to deflect laterally upon ~ng~ with second catch 88B
when arms 36 are pressed toward one another. Catch 88A has a stepped portion 91 which is deflected upon contact with the tapered back side of end portion 92. After clearing end portion 92, stepped portion 91 partially recoils from the deflection and resides beneath end portion 92, preventing arms 36 from returning to their outward positions. To release arms 36, they are pressed further inward, whereby catch 88A
completely clears end portion 92 of catch 88B and returns to SUBSTITUTE SHEEr (RU~E 26) , .. . . . . . . . .

W095121573 21 81 921 14 .~
it6 undef lected position . As arms 3 6 return to their outward positions, the back side of catch 88A slides along the tapered front side of end portion 92.
In the Pmho~ L of Figure 4B, locking means 86 comprises a ratcheting n; ~ to allow arms 36 to be r~;ntA;nPc~ in any of a number of positions between fully open and fully closed. In this: ho~;r L, a rocker arm 94 is pivotally coupled to arm 36A near a distal end 37 thereof. A
first end 96 of rocker arm 94 extends through a slot 98 in arm 36, and has a finger pad 100 with grooves or other textural features to reduce ~1 irrA7e when engaged by the user. A
plurality of teeth 102 are ~li cposed on a lateral side of rocker arm 94, and are configured to engage a pawl 104 on second arm 36B. A ~econd end 105 of rocker arm 94 extends through a slot 106 in second arm 36B. A biasing means such as a leaf spring 108 is coupled to rocker arm 94 and ~o arm 36A
to urge teeth 102 against pawl 104. In this way, as arms 36 are pressed inward, rocker arm 94 extends through slot 106 and teeth 102 ride sequentially along pawl 104 . When arms 3 6 are in a desired position, ~Leb~ e may be released and the ~:lly~ly. ~ of pawl 104 against teeth 102 prevents arms 36 from returning outwardly . When arms 3 6 are to be released, f inger pad 100 is pushed distally, pivoting rocker arm 94 in a clockwise direction, and rlicpnqA7ing teeth 102 from pawl 104.
The microsurgical ill~.LL, -ntc of the invention may have a number of different end-effectors suitable for performing a variety of surgical activities. Several ~ 1PC of such end-effectors are illustrated in Figures 5-10. It will be understood to those of ordinary skill in the art that the principles of the invention may be applied to various end-effector configurations in addition to those illustrated and described spP~ i f i c:~ 1 1 y here .
~he end-effectors in the microsurgical in21LL~ Ls of the invention may be configured for either pull-type or push-type actuation, ~PrPn~in7 upon whether the pull-type actuator of Figures 2A-2C or the push-type actuator of Figures 3A-3C is used. An exemplary ~mhorli--- of a pull-type end-effector is illustrated in Figure 5. End-effector 40 comprises a fixed SUBSTITUTE SHEET (RULE 263 Wo 95121573 218 ~ 9 21 PCTIUS95/0~885 jaw 112 attached to distal end 26 of outer shaft 22, ~nd a movable jaw 114 pivotally coupled to outer shaft 22 or to fixed jaw 112 at a pivot point 115. Inner shaft 46 has a distal end 116 pivotally coupled to a rearward portion 118 of - 5 movable jaw 114 proximal to pivot point 115. It is evident that, as inner shaft 46 is translated proximally relative to - outer shaft 22, movable jaw 114 pivots toward fixed jaw 112.
An; l Ary ~ of a push-type end-effector is illustrated in Figure 6. In this ~ 1, pivot point llS
is located near a proximal end of movable jaw 114, and inner shaft 46 is coupled to movable jaw 114 distal to pivot point 115. It may be seen that translation of inner shaft 46 distally relative to outer shaft 22 will pivot movable jaw 114 toward fiYed jaw 112.
The choice to use either a pull-type end-effector or a push-type end-effector is guided by a variety of c~n~ rations, including the g~l y of the end-effector, the function which the end-effector is ~ si~n~cl to perform, and the preference of the user for either push-type or pull-type actuation. For example, where high forces are needed in the end-effector to perform functions such as gripping or cutting, pull-type actuation is often ~LC:r~ d to eliminate the pn~;hil;ty of b~l~kl;n~ in inner shaft 46. In some end-effectors designed for pl~n~h;ng or shearing, push-type actuation is often preferred to provide tight, sliding contact between the jaws. In addition, the user may prefer the jaws of the end-effector to be normally closed when arms 36 of actuator 28 are in an outward position, such that the jaws are opened by pressing arms 36 inwardly. In such cases, the in~l~L Ls of the invention may be easily adapted for either pull-type or push-type actuation by proYiding the pull to close end-effector of Figure 5 with the push to close actuator of Figure 3, or by providing the push to close end-effector of Figure 6 with the pull to close actuator of 3 5 Figure 2 .
Figures 7-10 illustrate exemplary end-effector configurations suitable for performing various surgical functions. Figures 7A-7B illustrate two ~ ' ';- Ls of SUBSTITUTE SH~ET (RUl E26) wo 95/21573 PCT/US95/01885 2~ 16 grasping forceps. soth ~mho~ s are useful for z~ variety of ~uL~oses, however, the: 'o';- ~ of Figure 7A is particularly useful in mobilizing the internal mammary artery (IMA) for grafting to a coronary artery, as described below.
Both: `~ include a fixed jaw 112 and movable jaw 114 have gripping surfaces 120, 122 (liposP~ in opposition to each other so as to come into contact upon closing the jaws.
Gripping surfaces 120, 122 have textural features such as transverse grooves or teeth 124 to improve grip on tissue or other objects. Various well-known jaw designs may be used, such as DeBakey, Cooley, Mayo, or Babcock. Jaws 112, 114 may be of various sizes and shapes ~ r~n~;n~ upon the particular ~c,C~-luL~s for which they are adapted. In a particularly preferred ~ , jaws 112, 114 are adapted for very precise work on ~.. L.~ -ly small body structures in mi~ uL~ies such as CA~3G, having a length usually between 3 and 15 mm, preferably between 5 and 10 mm. In the of Figure 7A, jaws 112, 114 are tlicpnced at an angle, preferably between about 45 and 90-, relative to the distal direction defined by outer shaft 22, to facilitate grasping the INA when - 'il;7:ing it from the chest wall. In the ~mho~ of Figure 7B, jaws 112 are generally orthr~gonill with outer shaft 22 and are tapered in the distal direction to provide a distal portion of reduced size for ~nh~nrPcl access into small spaces and for use on 6.~L~ ly small -~Lu~LuL s.
Figure 8 illustrates a f~Lw~lLd ~.u~Ling scissors . ' d;- ~ of end-effector 40. In this: ` '; L, fixed jaw 112 and movable jaw 114 each have a sharpened cutting edge 126 along an inner side thereof. Novable jaw 114 is configured to pivot alongside fixed jaw 112 such that cutting edges 126 slide along one another in a shearing action. Usually, jaws 112, 114 are tapered to a sharp distal point 128. Preferably, in the scissor - ` -';- L, jaws 112, 114 are again adapted for use in CABG and other mi~:L~UL~Lies, having a length in the r~nge of 3 to 10 mm, and preferably 3 to 5 mm. Jaws 112, 114 may be ~liFp-,c-~-l at a variety of different angles relative to the distal direction defined by outer shaft 22, from +90 to SU3ST11~1TE SH~ET (Rul E26) --æ~
WO 95121573 P~ Ci66 -go, d~r~n~;n~ upon the particular cutting task to be perf ormed .
Figure 9 illustrates a rearward-cutting scissors L of end-effector 40. In this ~ odi- ~, jaws 112, 114 are much like those in the forward-cutting scissors ~ - ~; r ~ of Figure 8, having a sharpened cutting edge 12 6 and tapering to a distal point 128. ~lowever, to facilitate cutting in a proximal direction (toward the user), jaws 112 , 114 are ~ ro6~od at an angle between 90 and 270- relative to the di6tal direction as defined by outer shaft 22, such that distal points 128 point generally ~eaLw~-l.
Figure 10 illustrates a suture needle holder ~ t of end-effector 40. In this - t~odi- -~, jaws 112, 114 have contact faces 130, 132 di~spo~A in opposition to each other and which engage each other upon closure. Contact faces 130, 132 are adapted for gripping a suture needle tightly between jaw6 112, 114 and r-nir~ ting the needle for ~uL~OSes of applying a 6uture to a body ~j-ru~ e. Because such suture needles are typically steel or other hard metal, it is usually desirable to provide an insert 134 of hardened steel, carbide, or other metal on each j aw to enhance grip on the needle and to reduce wear on the gripping surfaces. Contact faces 130, 13 2 are pref erably provided with grooves, diamond knurl patterns, or other textural features to improve grip. In a preferred: ~ ir ~ jaws 112, 114 are adapted for holding a BV-l type suture needle suitable for coronary anastomosis and other microsurgical applications, the jaws usually having a length between 3 and 10 mm, and preferably between 3 and 5 rlm.
Jaws 112, 114 may also be curved about a transverse axis to facilitate holding a suture needle at various angles relative to shaft 22.
In the: ~ s described above, outer shaft 22 remains stationary relative to actuator 28 and inner shaft 46 i6 translated either distally or proximally relative to outer shaft 22. It should be understood that the in6~L -nt6 of the invention may al60 be configured 60 that inner shaft 46 remains stationary relative to actuator 28, and outer shaft 22 is translated relative to inner shaft 46. An example of the SUBSTITUTE SH~ET (RUl ~ 26) , . . . .

WO 95/21573 2 1 ~ 1 9 2 ~ oo~
latter configuration is illustrated in Figure 11. Arm8 36 are coupled to a body 140, which has an axial bore 141 in which proximal end 142 of inner shaft 46 is fixed. A proximal end 144 of outer shaft 22 i6 fixed to a sleeve 146 having flats 148 on the lateral sides of a proximal end thereof. A pair of links 150 are coupled at their outer ends 152 to arms 36, and at their inner ends 154 to flats 148 on sleeve 146. As described above, links 150 may be configured to translate outer shaft 22 either distally, as illustrated, or proximally relative to inner shaft 46 by positioning inner ends 154 either distal or proximal relative to outer ends 152.
Figure 11 further illustrates an exemplary ~mho~;- L of an end-effector with which an actuator configured to translate outer shaft 22 is particularly useful. In this I ' -~i- L, end-effector 156 comprises a clip applier for applying a surgical clip 158. End-effector 156 may be adapted to apply surgical clips or staples of various types and sizes, in7~ ~or example, a T' 1 ir~ or Atrauclip'Y brand ~urgical clip available from Pilling/Weck of Fort Washington, Pennsylvania. Such clips are a titanium or tantalum alloy or pure metal material and have a pair of distally-pointing legs 160 joined together at an apex 162 to form a modified U" or V" shape. End-effector 156 includes a pair of jaws 164 adapted to receive clip 158 between them. Jaws 164 extend distally from a bifurcated shank 166 attached to distal end 168 of inner shaft 46. Shank 166 has a straight proximal portion 170 and a flared distal portion 172. As outer shaft 22 translates distally, its distal end 174 enqages flared portion 172 of shank 166 and urges jaws 164 toward each other, thereby closing clip 158 held therebetween.
As illustrated in Figure 12, clip 158 may be positioned about a body structure such as a severed blood vessel BV.
Actuator 28 may then be actuated to close clip 158 on blood vessel BV to stop blood flow th~l- Lh~uuyll. A plurality of clips 158 may be applied to blood vessel BV to isolate a portion of the vessel or to ensure adequate ligation. This technique may be utilized during various surgical ~, vce~uLes inrlll~in~ CABG, as described more fully below.
SUBSTITUTE SHEET (RU~E 26) Wo s5nl573 21819 21 PCTIUS95/0188s End-effector 156 and clip 158 may have various sizes and shapes, but in a preferred: ' ~;r t, are adapted for use in performing CABG and other mi~:Lu,,uLy~ries. In such surgeries, legs 160 of clip 158 may have a length of 2 to 5 mm, preferably 3 to 4 mm, with the di6tance between legs 160 being 2 to 4 mm. Larger sizes of clips may be employed for larger - vessels. End-effector 156 is d;r -;on~7 accordingly.
It will be understood to those of ordinary skill in the art that an actuator config~7red to translate inner shaft 46 relative to a stationary outer shaft 22 may also be adapted to ~ctuate a clip applier like that of Figure 11. However, it is usually desirable to ~-; nt:~; n a constant distance between the user's hand and the body ~LLU~;LULd to which a clip is to be applied. Therefore, the actuator configuration illustrated in Figure 11 is generally preferred, since end-effector 156 remains stationary relative to actuator 28 as outer shaft 22 translates distally to close jaws 164.
The method of the invention will now be described with reference to Figures 13-17. While a preferred method of performing coronary artery anastomosis in a thoracoscopic CA~7G
ocelluLe will be described in detail here, it should be understood that the principles of the invention may be applied to a wide variety of surgical procedures , both conv~nt ; onA 7, open ~.o~-luLæs as well as m;n;r-lly-invasive procedures.
With the patient under general anesthesia, the patient's left lung L is deflated using well-known te~hn;q~ . Several small incisions are made in the left anterior chest through which trocar sleeves may be positioned to provide access into the thoracic cavity. As illustrated in Figures 13, trocar 61eeves 180 are positionable within the intercostal spaces I
between adjacent ribs R of the rib cage, typically having an outer ~7; ~r of less than 12 mm and an inner diameter of 5 to lo mm. Trocar sleeves 180 thus provide acce~ ports through which the illc,LLl Ls of the invention may be introduced into the thoracic cavity to perform the CABG
~)L UCe~l4L ~ .
An c-n~l~ scope 182 is then introduced into the body cavity through a trocar sleeve 180 to facilitate v;~llAl;7i~tion of the SUBSTITUTE SHEET (RU~ E 26) , WO95/21573 2181921 r~", c Idd~
thoracic cavity. 7~"Ansru~e 182 may include an eyepiece 184 for direct vi~llAli7~tion of the body cavity, and/or a video camera (not shown) mounted to body 185 for video-based viewing. Distal end 188 of ~-nA~nSCOre 182 may be steerable or 7.;RposP~' at an angle to facilitate vi~Ali7ation of the heart H. ~nAnscope 182 may further include a ~nnn~ctor 186 for connecting to a light source (not shown) for transmitting light to distal end 188 for ill~lminating the thoracic cavity.
FnA~7Scope 182 may be a commercially-available ~ ',oscope such as the 45- ~Ar~scope, available from Olympus, Medical Ir._L~, Ls Division, of Lake Success, New York.
The first surgical step to be performed in the CAEG
pLUCedUL.2 iS the mobilization of a graft vessel to create a new arterial blood source. Ordinarily, such a graft will be harvested before the patient has been placed on cardiopl~l y bypass and the patient ' heart has been stopped. One common type of graft vessel is a vein graft harvested from another part of the patient's body, usually the leg. A second common type of graft vessel is the internal mammary artery (IMA), typically the left IMA (LI.~A), in the anterior wall of the patient ' s chest. Prosthetic grafts may also be used. The IMA is often the preferred form of graft vessel, as it generally r~-;n7 A;nC patency for a longer period after the CAEG p~U~ dUL'a, requires less pLe:~alclLiOn for anastomosis, and is accessible within the thoracic cavity, obviating the need for inn;R;nn~ elsewhere in the body. For these reasons, the use of an IMA graft will be described here, although the l~ -hn;q7~ec described are equally applicable to vein grafts, prosthetic grafts, and other types of grafts.
The I.~A must be r'.iRRect~A from its native location in the anterior wall of the thoracic cavity. To accomplish this, a cutting inDL~ such as an electrocautery tool (not shown), a surgical knife (not shown) or scissors 190, along with grasping forceps 192, are illLL~duced t~rough trocar sleeves 180. The grasping forceps shown in Figure 7A are usually preferred for this purpose. These inDLL, --~ts may be introduced at various locations, but are usually inserted through trocar sleeves in the right lateral side of the chest SUB~I~UTE SHEET (RU~2!6) Wo 951~1573 2 1 8 ~ 9 2 ~ .,5/~l to allow the ill,L,, I,L to reach the anterior wall of the thoracic cavity. Using these ins L,, ~8, a section of the IMA, usually about 10 to 20 cm in length, is cut away from the ,,u,,uullding tissue with the vessel still intact. 8ranches of the INA which are too large to cauterize may be double clipped with small clips and divided between the clips. A clip - applier like that illustrated in Figures 11-12 may be used for this purpose. A section of the IMA is chosen which, when cut distally, will reach the desired anastomosis site on the LAD.
This mobilized section of the I~SA must then be isolated to stop blood flow through it. Such isolation may be accomplished by introducing a removable clamp (not shown) into the thoracic cavity and applying the clamp to the I~A near the distal end of the mobilized section but proximal to the point at which the vessel is to be LLA~ F~ I ed. A convQnti~ns~l clamp such as a Fogarty clamp available from Baxter ~lealthcare Corp.of l~cGaw Park, Illinois may be used for this purpose. A
clip applier, such as that illustrated in Figures 11-12, is then introduced into the thoracic cavity and one or more surgical clips are applied to the INA distal to the point at which it i6 to be transected. A scissors 190 or other cutting irl.. L, L is then used to transect the IMA near the distal end of the r ~ i 1 i 7r~-l section between the removable clamp and the surgical clips.
The distal end of the --~i l i 7Q~ IMA is then prepared for anastomosis. Usually, forceps 192 are used to withdraw the mobilized section from the thoracic cavity through one of trocar sleeves 180. The distal end is then plc:pa,~d for anastomosis by cutting away a distal portion of the pedicle ~.uLLuUll~ing the vessel so that a distal segment of the vessel is exposed. The distal end of the vessel is transected at a nu., pe~- Ai~lllar angle suitable for a~t~ t to the LAD in a fishmouth configuration. The vessel may then be returned to the thoracic cavity.
The patient must then be placed on cardioplllr -ry bypass, and the heart must be stopped. If the operation is to be performed using min;r~l ly-invasive techniques, these must be accomplished without making a sternotomy or other gross SUBSTITUTE SHEET ~RUL~26) .. .. . . .

J ~
WO 9!i/21573 P~,llu_,_, lOo_ 21 8f 921 22 thoracotomy in the patient's chest. Min;r~lly-invasive techniques for est~hlichin~ cardiop~ ry bypass and arresting the heart without opening the patient ' s chest are described in cop~n~lin~ application Serial No. 08/023,778, which has been irl`UL~JULC~ted herein by reference, as well as in copQn~;n~ applications Serial No. 07/991, 188, filed r~ ~
15, 1992, and Serial No. 08/123,411, filed September 17, 1993, which are both hereby incuL ~JUl clted herein by ref erence in their entirety.
Once the heart has been stopped and the patient is supported on cardiop~l y bypass, the anastomosis of the IMA to the LAD may be perfor~ed. As illustrated in Figure 14, an opening O is formed in the LAD at the desired location of the anastomosis, distal to the lesion which is to be bypassed.
A scissors 190 or other cutting ina~LI is il-~Lvduced through a trocar sleeve 180 and a small ;nr;ci~-n is formed in the LAD, usually about 2 to 5 mm in length. The rearward cutting scissors ill~la~L~ted in Figure 9 may also be useful f or this purpose, ~r--n~; ng upon the orientation of the heart and/or LaD relative to the user and relative to the trocar sleeve through which the in_LL, is i.-LLu,luced.
It may be n~ ~s~,y, either before or After an opening is formed in the LAD, to dissect a small section of the I~D on either side of the ana~7l lii;R site away from the epicardium to obtain better access for performing an anastomosis.
Scissors 190 or other cutting inc.LL, ~ may be used for this purpose. The rl; ccect~ section of the LAD may be retracted away from the surface of the heart using conventional means such as Retract-O-Tape Vascular Loops available from Quest Medical of Dallas, Texas.
To perform the anastomosis, the IMA is sutured to the I~D
over opening O. As illustrated in Figure 15, a grasping in~L, ~ such as forceps 192 is ir,~Luduved through a trocar sleeve for holding the IIIA in position during the anastomosis.
One or more needle drivers 194 are also introduced into the thoracic cavity, as well as a suture 196, usually having needles 198 on both ends. Needle drivers 194 are used to r~n;rlll:~te needles 198 so as to suture the distal end of the SUBSTITUTE SHEET (RU~ F26) WO 95121573 ~ 18 ~ 9 21 PCTNSsS/01885 IMA to the LAD, under vic~ ;z~tion by means of c~ os~u~p 182 (Figure 13 ) or other visualization device.
Various technigues may be used f or suturing the IMA to the LAD. An exemplary tprhnique is illustrated in Figures - 5 16A-16E and is described comprehen6ively in Kirklin and Barratt-Boyes, Cardiac Surqe~, pp. 207-277 (1986), the disclosure of which is in,,uL~uLaLed herein by reference. At least one pair of needle drivers 194 are required, along with a grasping in~-LI, L such as forceps 192. It may be seen from the illustrations that the suture is passed sequt~ntiAlly through the wall of the LAD around the edges of opening 0 and through the wall of the INA around its distal end 200. This is repeated until suture loops have been made about the entire circumf erence of the IMA spaced approximately 0 . 3 mm apart .
The loops are drawn tight and the cuture is tied off in a conventional manner to provide a secure and fluidly sealed att~ of the IMA to the LAD, as illustrated in Figure 17.
The removable clip (described above) is then removed from the IMA, allowing blood to f low through the IMA and into the LAD
after the heart has been restarted.
When the anastomosis has been completed, the patients heart is restarted and car~; or~ ry bypass is discontinued.
All trocar sleeve6 and ~Annl~l AC are removed from the patient, and the thoracic ~ n~ i onC and arterial and venous punctures are closed. The patient is then ~ecuve:Led from anesthesia.
The microsurgical ir ,LL, ts of the invention are ~rP~iA~lY adapted to facilitate the ultra-precise microsurgical steps of thorAcoscopio CABG. The IMA, LAD, and other body structures r-nir-lAted during the CABG ~Lùced4L.
are ~ LL~ ly small, with ~ t~:L~ in the range of 1 to 4 mm, and are relatively fragile ~L~U~;L4reS which must be handled gently and precisely. The microsurgical forceps, scissors, needle drivers, and clip appliers of the invention are well-suited to grasping these structures, making the nPCPcsAry LL~.se~ Lions, incisions, and ligations, and applying tU~LLI ~Y
small sutures, allowing anastomoses to be perf ormed accurately, efficiently, repeatably, and with minimal trauma.
The in~iLL, Ls of the invention not only have the very small SUBSTITUTE SHEET (RU~ ~26) , . . . .

WO 95/21573 ~181~ ~ 2 ~ PCT/US95/01885 ~9i -i~nC nec~ssary for such mi.l~,Du ~ly, but the means of holding and actuating these inD~L Ls allow ex~L ly precise actuation and control of the end-effectors. Moreover, the elongated, low-profile configuration, high stiffness, and optimal end-effector geometries of these il-~,LLI c facilitate the performance of CABG and other operations through small i nri cion8 or trocar sleeves rather than through the gross, open thoracotomies used in conventional open-heart surgery.
While the above is a complete description of the preferred ~mhorli.- Ls of the invention, various alternatives, modifications and equivalents may be used. Therefore, the above description should not be taken as limiting the scope of the invention, which i5 defined by the Aly~ G~ claims.
1~ .

SUBSTITUTE SHEET (RULE26)

Claims

What Is Claimed Is:

1. A microsurgical instrument comprising:
an outer shaft having a proximal end, a distal end, and an axial lumen therebetween;
an inner shaft slidably disposed in the axial lumen and having a proximal end and a distal end;
an end-effector coupled to the distal end of the inner shaft and movable relative to the outer shaft; and an actuator at the proximal end of the outer shaft, the actuator comprising:
a first arm having a proximal end and a distal end, the proximal end being pivotally coupled to a first shaft selected from the outer shaft and the inner shaft, and the distal end being disposed on a first lateral side of the outer shaft and biased outwardly to form an acute angle therewith;
a second arm having a proximal end and a distal end, the proximal end being pivotally coupled to the first shaft, and the distal end being disposed on a second lateral side of the outer shaft opposite the first lateral side and biased outwardly to form an acute angle therewith;
a first link having an outer end and an inner end, the outer end being coupled to the first arm at a first pivot point, and the inner end being coupled to a second shaft selected from the outer shaft and the inner shaft; and a second link having an outer end and an inner end, the outer end being coupled to the second arm at a second pivot point, and the inner end being coupled to the second shaft;

wherein the first and second arms are symmetrically pivotable to translate the inner shaft relative to the outer shaft, thereby actuating the end-effector.

2. The instrument of claim 1 wherein the end-effector is pivotally coupled to the outer shaft at a first point and pivotally coupled to the inner shaft at a second point, wherein translation of the inner shaft relative to the outer shaft moves the end-effector.

3. The instrument of claim 2 wherein the first and second points are separated by a distance which is less than about 5 mm.

4. The instrument of claim 1 wherein the outer shaft has a diameter of less than about 5 mm.

5. The instrument of claim 1 further comprising a fixed jaw at the distal end of the outer shaft, wherein the end-effector comprises a movable jaw movable between an open position separated from the fixed jaw and a closed position in engagement with the fixed jaw.

6. The instrument of claim 5 wherein the movable jaw has a gripping surface disposed in opposition to a gripping surface on the fixed jaw.

7. The instrument of claim 5 wherein the movable jaw has a cutting edge movable in a shearing relationship with the fixed jaw.

8. The instrument of claim 1 wherein the first and second links are arranged such that a transverse force exerted through the first link on the second shaft is opposed by a transverse force exerted through the second link on the second shaft.

9. The instrument of claim 8 wherein the inner ends of the first and second links are equidistant from the proximal end of the second shaft.

10. The instrument of claim 1 wherein the first and second arms are hingedly coupled to the first shaft.

11. The instrument of claim 10 wherein the first and second arms are rigid.

12. The instrument of claim 10 further comprising spring means for outwardly biasing the first and second arms such that the distal ends thereof are spaced apart from the outer shaft.

13. The instrument of claim 1 wherein the inner ends of the first and second links are distal to the outer ends of the first and second links.

14. The instrument of claim 1 wherein the inner ends of the first and second links are proximal to the outer ends of the first and second links.

15. The instrument of claim 1 wherein the first pivot point is closer to the proximal end of the first arm than to the distal end of the first arm, and the second pivot point is closer to the proximal end of the second arm than to the distal end of the second arm.

16. The instrument of claim 1 further comprising means for locking the first and second arms in a closed position.

17. A microsurgical instrument comprising:
an outer shaft having a proximal end, a distal end, and an axial lumen therebetween;
an inner shaft slidably disposed in the axial lumen and having a proximal end and a distal end;
a fixed jaw at the distal end of the outer shaft;
a movable jaw coupled to the distal end of the inner shaft and movable relative to the fixed jaw; and an actuator at the proximal end of the outer shaft, the actuator comprising:

a first arm having a proximal end and a distal end, the proximal end being pivotally coupled to a first shaft selected from the outer shaft and the inner shaft, and the distal end being disposed on a first lateral side of the outer shaft and biased outwardly to form an acute angle therewith;
a second arm having a proximal end and a distal end, the proximal end being pivotally coupled to the first shaft, and the distal end being disposed on a second lateral side of the outer shaft opposite the first lateral side and biased outwardly to form an acute angle therewith;
a first link having an outer end and an inner end, the outer end being coupled to the first arm at a first pivot point, and the inner end being coupled to a second shaft selected from the outer shaft and the inner shaft; and a second link having an outer end and an inner end, the outer end being coupled to the second arm at a second pivot point, and the inner end being coupled to the second shaft, the first pivot point being closer to the proximal end of the first arm than to the distal end of the first arm, and the second pivot point being closer to the proximal end of the second arm than to the distal end of the second arm;
wherein the first and second arms are symmetrically pivotable such that the first and the second links exert symmetrical forces on the inner shaft to move the movable jaw relative to the fixed jaw.

18. A method of endoscopic manipulation of a body structure within a body cavity, the method comprising:
providing an instrument having a shaft with a distal end and a proximal end, a pair of jaws at the distal end movable relative to each other, and a pair of arms coupled to the proximal end, each arm having a proximal end coupled to the proximal end of the shaft and a distal end biased outwardly from the shaft forming an acute angle therewith;
introducing the distal end of the shaft through a percutaneous penetration into the body cavity;
viewing the body cavity by means of a scope introduced through a percutaneous penetration; and pressing inwardly on a distal portion of at least one arm to symmetrically pivot both arms toward the shaft, thereby closing the jaws on the body structure.

19. The method of claim 18 wherein the arms are each coupled to a proximal end of a rod arranged coaxially with the shaft and movable axially relative thereto, at least a first of the jaws being coupled to a distal end of the rod, wherein the first jaw is moved by translation of the rod.

20. The method of claim 19 wherein pressing inwardly on the arms exerts axial and transverse forces on the rod, wherein a first transverse force exerted on the rod by a first arm is opposed by a second transverse force exerted on the rod by a second arm.

21. The method of claim 19 wherein each arm is coupled to the rod by a link, each link being coupled at a first end to the proximal end of the rod and at a second end to a pivot point in a proximal portion of an arm, wherein each arm may be pressed at a point which is separated from the pivot point by at least half of the length of the arm.

22. The method of claim 19 wherein at least a first jaw is pivotally coupled to the shaft at a first point and pivotally coupled to the rod at a second point, wherein translation of the rod relative to the outer shaft pivots the first jaw.

23. The method of claim 18 further comprising positioning an access cannula in the percutaneous penetration, the access cannula having an inner passage through which the shaft is introduced into the body cavity.

24. The method of claim 23 wherein the inner passage has a diameter in the range of 3mm to 10 mm.

25. The method of claim 18 wherein the body structure comprises a vessel selected from the group consisting of coronary arteries, internal mammary arteries, aortas, and saphenous veins.

26. The method of claim 18 wherein closing the jaws on the body structure engages the body structure between opposing gripping surfaces on the jaws to grip the body structure therein.

27. The method of claim 26 wherein the body structure comprises an internal mammary artery, the method further comprising dissecting a portion of the internal mammary artery from surrounding tissue while gripping the internal mammary artery between the jaws.

28. The method of claim 18 wherein at least one of the jaws comprises a cutting edge movable in a shearing relationship with the other jaw, wherein closing the jaws on the body structure cuts the body structure.

29. The method of claim 28 wherein the body structure comprises a coronary artery, wherein the jaws are closed on a wall of the coronary artery to cut an opening therein.

30. The method of claim 29 further comprising attaching a graft vessel to the coronary artery under visualization by means of the scope such that a lumen in the graft vessel is in communication with the opening in the coronary artery.

31. The method of claim 30 wherein the step of attaching comprises suturing the graft vessel to the coronary artery by means of a suture manipulating instrument.

32. The method of claim 31 wherein the suture manipulation instrument comprises a shaft with a distal end and a proximal end, a pair of jaws at the distal end movable relative to each other, and a pair of arms coupled to the proximal end, each arm having a proximal end coupled to the proximal end of the shaft and a distal end biased outwardly from the shaft forming an acute angle therewith, whereby the arms may be pivoted toward the shaft to close the jaws on the suture.

33. The method of claim 31 wherein the step of suturing further comprises holding a portion of the graft vessel with a grasping instrument.

34. The method of claim 33 wherein the grasping instrument comprises a shaft with a distal end and a proximal end, a pair of jaws at the distal end movable relative to each other, and a pair of arms coupled to the proximal end, each arm having a proximal end coupled to the proximal end of the shaft and a distal end biased outwardly from the shaft forming an acute angle therewith, whereby the arms may be pivoted toward the shaft to close the jaws on the graft vessel.

35. The method of claim 31 wherein the suture manipulation instrument is introduced through a percutaneous intercostal penetration in the patient's chest.

36. A microsurgical clip applier comprising:
an outer shaft having a proximal end, a distal end, and an axial lumen therebetween;
an inner shaft slidably disposed in the axial lumen and having a proximal end and a distal end;
a pair of jaws fixed to the distal end of a first shaft selected from the outer shaft and the inner shaft, the jaws being configured to hold a surgical clip therebetween; and an actuator at the proximal end of the outer shaft for closing the jaws, the actuator comprising:
at least a first arm having a proximal end and a distal end, the proximal end being pivotally coupled to the first shaft, and the distal end being disposed on a first lateral side of the outer shaft and biased outwardly to form an acute angle therewith; and a first link having an outer end and an inner end, the outer end being coupled to the first arm at a first pivot point, and the inner end being coupled to a second shaft selected from the outer shaft or the inner shaft, whereby the second shaft is translated relative to the first shaft when the first arm is pivoted toward the outer shaft; and means coupled to the second shaft for closing the jaws in response to translation of the second shaft relative to the first shaft.

37. The clip applier of claim 36 wherein the means for closing the jaws comprises a bifurcated shank connecting the jaws to the first shaft, the shank having an outwardly flared portion for engaging the distal end of the second shaft.

38. The clip applier of claim 36 wherein the actuator further comprises:
a second arm having a proximal end and a distal end, the proximal end being pivotally coupled to the first shaft, and the distal end being disposed on a second lateral side of the outer shaft opposite the first lateral side and biased outwardly to form an acute angle therewith; and a second link having an outer end and an inner end, the outer end being coupled to the second arm at a second pivot point, and the inner end being coupled to the second shaft;
wherein the first and second arms pivot symmetrically to translate the second shaft relative to the first shaft.

39. The clip applier of claim 36 wherein the first shaft comprises the inner shaft and the second shaft comprises the outer shaft.