INTRAOCULAR LENS IMPLANTATION

Abstract: A surgical forceps (21) and method of implanting an intraocular lens using same. The forceps (21) comprise arms (22e and 23e) which cross-over at a point (24), said point maintained in the incision (14) so as to minimize incision size.

Description: INTRAOCULAR LENS IMPLANTATION Background of the Invention and Prior Art This invention relates generally to intraocular l implantation, and more particularly concerns apparatus method for achieving such implantation via a very small surgi incision in the corneo-scleral limbus of the eye. In the past, forceps have been used with blades t clamp the plastic lens for introducing it into the eye vi relatively wide wound or incision in the corneoscleral limbus. typical wound was required to have a width of about 7 millimeters in order to pass the forcεp blades and to al spreading of the blades to release the plastic lens in the eye. Problems encountered included laceration of the elas silicon lens, and undesirable sudden release and rapid unfold of the lens (as opposed to gentle release) causing injury intraocular tissue, due to inability to separate the bla widely and gently. The usual wide incision is undesirable due the amount of suturing required to close the wound, and t required for such suturing, increased or undesirably lo convalescence time, increase in astigmatic complica ion difficulty in preventing collapse of the intraocular chamb during the operation, and increased risk of post-operati complications. Further, plastic lenses could and did at ti become captured by the blades of prior forceps, requirin dangerous instrumentation to release the lens from the grasp o such forceps. Summary of the Invention It is a major object of the invention to provide metho and apparatus, overcoming the above problems and difficultie Basically the invention permits wide separation of the blades a gentle release of the folded lens within the eye, while motio is transmitted to the blades via a very narrow incision. The method involves implanting a plastic lens into t eye lens zone from which a natural but cataractous lens has ju been removed (or removed in the past) as via a narrow surgic incision in the corneo-scleral limbus, and while using a force having blades projecting from or beyond cross arm portio defining a cross-over locus. The method includes the steps: a) manipulating the forceps to introduce the blad and clamped plastic lens through the incision and in said zone, and to place the cross arm portions in sa incision; b) further manipulating the forceps to spread t blades thereby releasing the plastic lens t accommodate to said zone, and thereafter relative closing together the blades while maintaining t cross-fixation arm portions at or proximate sai incision; c) and withdrawing the relatively closed togeth blades from said zone and via said incision. Typically, the b) step is carried out to separate blades to an extent much wider than the incision; and the bla are, for example, separated within the eye to an extent excess of 4 mm, and typically between 6-8 mm, the narrow surgi incision having a width less than about 3 mm. Further, the plastic lens is typically folded and h in elastically folded state, by the blades, while bei introduced through the narrow incision; and the blades are slo and gently spread apart, by pressure on the forceps hand producing motion transmission through the narrow incision, allow controlled elastic unfolding of the lens for precis interfitting with the eye tissue. Such full excursion bl separation is achieved by force transmission through the cr fixation arm portions which in the wound do not require more t 1 to 2 mm space or size. Finally, the improved forceps is not only useful as intraocular lens holder, but also as a utility forceps, capab of passing through a small puncture wound to insert a le implant, or grasp an intraocular foreign body for its removal better positioning—all through the small puncture wound. These and other objects and advantages of t invention, as well as the details of an illustrative embodimen will be more fully understood from the following specificati and drawings, in which: Brief Description of the Drawing Figure 1 is a side view of a cataractous opaque lens; Figure 2 is a side view of the cataractous opaque le within the lens capsule in the eye; Figure 3 is a side view of the anterior lens capsul after removal of the opaque cataract lens and the central portio of the anterior capsule; Figure 4 is a front view of the cataractous lens seen in Figure 1, showing zonula fibers holding the capsule; Figure 5 is a front view showing the location of surgical 1 to 2 mm incision in the corsoscleral tissue, outwardl from the limbus; Figure 6 is a front view showing prior straight forcep with arms and blades whose narrow separation is limited by a 3 incision in the corsoscleral. limbal tissue; Figure 7 is a front view showing the forceps of t invention with cross action arm portions passing through t corsoscleral limbal tissue, the forceps blades having been widel separated, i.e. not limited as in Figure 6; Figure 8-12 are sequential views showing steps in the intraocular implantation of a plastic lens, using the forceps the present invention; Figure 13 is an enlarged frontal view of a plastic le of the type to be implanted; Figure 14 is a perspective view of the Figure 13 le partially folded; Figure 15 is a frontal view of the forceps of t invention with blades holding the plastic lens in fold condition and positioned within the eye, as related to the le capsule; Figure 16 is a view like Figure 15, after the bla have been separated, showing elastic expansion of the plas lens between the separated blades, with no remaining danger elastic compression, and as dimensionally related to the nar Figure 17 is a schematic view of the eye; and Figure 18-20 are views showing modifications. Description of the Preferred Embodiment Referring first to Figures 1 and 2, they show, in si view, and schematically, a cataractous opaque lens 10, bound peripherally by zonula fiber 11, and located between anterior a posterior portions 12a and 12b_ of the lens capsula. They e outline appears schematically at 13, and Figure 17 is a secti accurately showing corresponding parts, as well as other part of the eye. Figure 3 shows the capsule void 12_c after removal the cataractous lens tissue. Figure 4 is a front view of t lens 10 seen in side view in Figure 1. Figure 5 is a schematic frontal view of the ey showing a narrow (for example about 3 mm wide) incision puncture 14 in the corneoscleral tissue 15, at a short distan (as for example about 2 mm) from the limbus 16, the latt designating the merging of light (sclera) and dark (ir periphery) zones of the eye. The present invention mak possible the use of -such a narrow, i.e. short, puncture wound, opposed to the prior very wide incision, indicated by brok lines 14 ^ which was necessary in order to implant a plastic silicon lens into the capsula 12. Such a wide (typically 15- mm) incision requires much more suturing than is required for t short incision or puncture wound 14, and requires a long convalescence period, with increased risk of post-operati complications. The cataractous lens is more recently removed phacoemulsification with ultrasonic vibration fragmentation a aspiration via the puncture 14, leaving jagged anterior "leave or serrations 17 in the anterior capsula portion 12a; t posterior capsula portion 12b remains c-lear. Anteri capsulatomy removes the central anterior capsula, leaving spa indicated at 12c in Figure 3. Figure 6 shows a straight forceps 18 having an arm 1 continuing forwar-dly to merge with a blade 19b, and an arm continuing forwardly to merge with a blade 20b. The blades h been inserted through a narrow (3 mm for example) incision indicated at 14' , and that incision characteristically sever limits the separation of the blades to release a plastic silicon lens clamped between them; for that reason, it previously considered necessary to form a wide incision, previously referred to at 14a, in order to release the plas replacement lens. Such a large wound tends to allow fluid esc from the eye, with impending ocular collapse and damage in intraocular tissue. The forceps of the present invention is sh schematically at 21 in Figure 7. That forceps is characteri by an arm 22a extending generally forwardly to merge w diagonally rightwardly and forwardly extending cross-over port 22b, the latter terminating at blade 22c_. Similarly, a sec arm 23a extends generally forwardly to merge with diagona leftwardly and forwardly extending cross-over portion 23b, latter terminating at forwardly extending blade 23c_ parallel blade 22£. The blades also extend forwardly relative to diagonals. Note that the cross-action portions 22b and 22£ laterally displaced and slide adjacent one another by sequence release manipulation of the forceps arms so that the cross-o point 24 remains in, or very closely proximate to, the punct locus 14, as during expansion of the blades from their initia inserted broken line positions 22c_' and 23c_' to their expan solid line positions 22£ and 23£. This then allows a wide deg of such expansion to free the plastic lens within the capsula without restriction imposed by the narrow puncture 14. Arms and 23 defining handles 22e -and 23e are typically joined toget at their outer ends 22d and 23d. Figures 8-12 show the implanta ion sequence for elastic, molded plastic or silicon lens implant 25 as represent in Figure 13. That lens has an intermediate and bead-li optical portion 25a, and two oppositely extending haptics tangs 25b_ and 25£. It is foldable about a lengthwise axis 26, seen in Figurel4, so as to be clamped or held between the blad 22£ and 23£, as during implantation viewed in Figure 8 and 9, and via the narrow (about 3 mm or less) puncture 1 Typical dimensions appear in Figs. 13 and 14. In Figures 8 and 9 the arm cross-over (cross-fixatio point or locus 24 is very close to the blades, whereby t blade3s are held near one another, with the folded le therebetween, for insertion through the narrow puncture. On insertion is completed, characterized by location and retenti of the forward tang 25b into the tissue bounding the lens cavi or void, as seen in Figure 15, the blades are allowed to slow separate as by slow release of manual pressure on the bow spring arms 22a and 23a of the forceps, and the forceps is al manipulated slightly lengthwise (forward or backward) to mainta the slightly lengthwise (forward or backward) to -maintain t cross-over point 24 in, or proximate, the puncture 14. Th allows ultimate wide separation of the blades, to between 4 to mm, as seen in Figs. 10 and 16, without restriction imposition the small narrow puncture. The width of the puncture is le than about 3 mm. Note that the cross-over point 24 has mov away from the blades in Figs. 10 and 11. Anglec defined by th portions 22b and 23b is between 75° and 105 ® The blades remain approximately parallel during their excursions. In Figure 11, the elastically expanded (unfolded artificial lens has dropped away from between the blades, leavi them free for relative closure, as seen in Figure 12. In t latter, the cross-over point 24 has moved relatively back towa the blades; the blades are closed together and they a positioned for retraction through the puncture. As referred to above, the forceps of the pres invention, has utility, not only as an intraocular lens hol but also as a utility forceps, capable of passing through a sm puncture wound to insert a lens implant, or grasp an intraocu foreign body for its removal or better positioning, all thro the small puncture wound. The specific angulations of the cross fixation portions, their lengths, and the sizes of the two blades, related to the narrow puncture wound, may vary somewhat depend upon the specific use and functioning of the forceps. In Figure 18, the blades 22£ and 23£ and the cross o portions 22b and 23b of the arms define a first plane P- j _ and remainders of the arms 22a and 23a define a second plane P 2 . angle β between P- 1, and P 2 is between 100* and 130*. Arms 22a and 23a join the diagonals at elbows at 22J: and 23:f. The cross-o locus appears at 24. The dimension d, 22_f to 24 is about 4 m the dimension d- from 24 to the blade inner end, 37 is abou mm; and the dimension d 3 , which is the blade length, is abou mm. In Figure 19, each blade 22£ and 23£ has a shal concave inner surface 38 to match (or approximately match) surface convex curvature 39 of the plastic molded lens 25 h folded in half at 40. Each blade also has a second inner surf 41 which is approximately flat to match the flat outer surface of the folded haptic 25£. In Figure 20, at least one of the diagonal portio such as arm portion 23b, has an interior, lengthwise extendi irrigation channel or annula 43, for passing eye irrigat liquid to outlet 44, in the eye, when the blades are located the eye. Passage 45 in arm 23a feeds liquid to channel 43, a under pressure sufficient to keep the anterior and posteri chambers in the eye from collapsing. Persons skilled in the art will readily appreciate th various modifications can be made from the preferred embodime thus the scope of protection is intended to be defined only the limitations of the appended claims.

Claims: Claims 1. A surgical forceps useful for eye surgery wher an incision is made in the eye corsoscleral tissue, the incis being less than about 3 mm in width, said forceps comprising: a) a first arm extending generally forwardly merge with a first diagonal portion defined said arm, said diagonal portion extend forwardly and rightwardly, and a first bl carried by said first diagonal portion, b) a second arm extending generally forwardly merge with a second diagonal portion defined the second arm, said second diagonal port extending forwardly and leftwardly, and a sec blade carried by said second diagonal portion, • c) said first and second diagonal porti together defining a cross-over point adapted to shifted away from the blades as the blades expanded relatively away from one another in _ eye; d) whereby motion may be- transmitted from arms to the blades facilitating expanding of blades while the cross-over point is maintained or proximate to said incision. 2. The forceps as defined in Claim 1 wherein overall cross-dimensions of the diagonal portions of the arms the cross-over point at all times during blade expansion is l than about 3 millimeters. 3. The forceps, as defined in Claim 1 wherein sa blades and said diagonal portions of the arms define a fir plane, and the remainders of said arms define a second plan there being an angle β between said planes where β is between 100 β and 130°. 4. The forceps as defined in Claim 1 wherein ea blade has a concave surface portion to match or approximate match the surface convex curvature of a plastic molded lens, a a second surface portion to match or approximately match t outer surface of a plastic molded lens haptic. 5. The forceps as defined in Claim 1 wherein at lea one of said diagonal portipns defines an irrigation channel pass irrigation liquid to the eye interior when the blades a located in the eye interior. 6. The forceps as defined in Claim 1 wherein sa blades extend forwardly relative to said diagonal portions. 7. The method of intraocular implantation of a plast lens in the eye lens zone from which a natural lens has be removed via a surgical incision in the corneo scleral limbus, t method employing a surgical forceps having blades projecti beyond cross-over arm portions defining a cross-over locus, t blades clamping the plastic lens to be implanted, said meth including the steps: a) manipulating the forceps to introduce t blades and clamped plastic lens through sa incision and into said zone, and to locate sa locus at or closely proximate to said incision, b) further manipulating the forceps to spre apart the blades thereby releasing the plas lens to accommodate to said zone, and thereaf relatively closing together the blades wh maintaining the cross-over locus at or proxim said incision, c) and withdrawing the relatively closed toget blades from said zone and via said incision. 8. The method of Claim 7 wherein said b) step carried out to separate the blades over their entire lengths an extend wider than the incision. 9. The method of Claim 8 wherein the blades a separated to an extent in excess of 7 mm, and said incision ha width of 3 mm or less. 10. The method of Claim 7 including forcibly foldi the plastic lens and effecting clamping of the folded lens by t blades prior to said a) step, the folded lens then bei introduced through said incision. 11. The method of Claim 10 wherein said b) st release of the plastic lens allows elastic unfolding of the le within said zone. 12. The method of Claim 7 wherein said b) st includes displacing the forceps generally lengthwise to mainta the cross-over locus in the incision as the blades are spre apart.

Inventors: MCDONALD HENRY H, MCDONALD, HENRY, H.
Applicants: MCDONALD HENRY H, MCDONALD, HENRY, H.
Application year: 1988
Main classification: A61F2
IPC codes: A61F2