Lense arrangement for vitreoretinal surgery

A lens arrangement for use in vitreoretinal surgery includes a contact lens element including a posterior surface having a shape adapted to fit an average cornea for placement on a patient's eye and an anterior surface. The contact lens element transmits light emanating from the patient's eye for viewing a structure of the patient's eye. A flange surrounds and holds a peripheral region of the contact lens element and extends radially onto the scleral region of the patient's eye. The flange has a posterior surface with a shape adapted to fit an average scleral curvature so that the flange rests on the sclera for stabilizing a position of the contact lens on the patient's cornea. The flange includes at least one opening allowing access to an incision through which a surgical tool or instrument may be inserted into the eye.

BACKGROUND OF THE INVENTION 
The invention relates to a lens arrangement for observation and surgical 
treatment of the vitreous or retina of the eye, and more particularly for 
use in vitreoretinal surgery. 
Direct ophthalmoscopy lenses which create a virtual image within the eye 
and indirect ophthalmoscopy lenses which create a real image outside of 
the eye are two lens types which have been used for fundus observation and 
as aids in the surgical treatment of the eye. Known lenses of this type 
that are used in vitreoretinal surgery are maintained on the eye through 
the use of a handle that is held by an assistant during the surgery. A 
problem exists with the use of such a handle in that the assistant may 
require considerable prior experience in vitreoretinal surgical 
procedures, and that the exact lens position required may be tiresome as 
well as difficult to maintain over the course of the surgery, especially 
if there is some movement of the eye or if some movement of the imaging 
lens is desired to aid the physician in his work. 
It is also known to hold such lenses in place with the use of a suture down 
ring. The suture down ring is comprised of metal or other bio-compatible 
material and has one or more extending fingers or leg portions around 
which sutures, which have been sewn into the sclera, are tied. The lens, 
which may be, for example, a plano-concave direct ophthalmoscopy lens or 
an indirect ophthalmoscopy lens system comprised of two or more elements, 
slips into the suture down ring and is thereby stabilized and centered 
over the cornea. Commonly, a sterile interface solution is used in 
conjunction with the lens to produce an optical interface of the lens with 
the eye. The suture down ring has been successfully used, but because its 
use involves a suturing procedure it could be desirably avoided were there 
to be a suitable non-invasive alternative. 
SUMMARY OF THE INVENTION 
It is an object of the invention to provide a lens arrangement to 
facilitate vitreoretinal surgery. 
It is a further object of the invention to provide a lens arrangement to 
facilitate vitreoretinal surgery which involves a non-invasive 
stabilization of an ophthalmoscopy lens on the eye without using a 
manually held handle. 
The above and other objects are accomplished according to the invention by 
the provision of a lens arrangement for use in vitreoretinal surgery, 
including a contact lens element having a posterior surface adapted to fit 
an average cornea for placement on a patient's eye, and an anterior 
surface, the contact lens element transmitting light emanating from the 
patient's eye for viewing a structure of the patient's eye; and a flange 
surrounding and holding a circumferential edge of the contact lens element 
and extending radially onto the scleral region of the patient's eye, the 
flange having a posterior surface with a shape allowing it to rest on the 
scleral portion of the eye for stabilizing a position of the contact lens 
element on the patient's cornea, the flange having one or more openings 
allowing access to an incision through which a surgical tool or 
instruments may be inserted. 
In a preferred embodiment the one or more openings comprise a plurality of 
spaced apart recesses each having an opening at the out peripheral edge of 
the flange and extending radially inwardly, the opening and inward radial 
extent of each recess allowing access to an incision through which a 
surgical tool or instruments may be inserted. 
In an alternative embodiment, the stabilizing portions of the flange 
existing between the one or more openings or recesses may include vacuum 
suction ports or channels designed to conduct a partial or high vacuum to 
further enhance the stable positioning of the lens on the eye. 
The contact lens element may comprise a direct ophthalmoscopy lens, for 
example, of the plano-concave, convex-concave or bi-concave type, or 
alternatively may be part of a multi-element indirect ophthalmoscopy lens. 
Further, the contact lens element and flange may comprise an integral, one 
piece unit made of the same material. Alternatively, the flange may 
comprise a separate component made of the same or different material from 
the contact lens element. In the latter case the contact lens element may 
slidably fit within a central opening of the flange or may be releaseably 
connected by other suitable mechanisms, such as a screw connection 
friction fit or a bayone connection. 
As desired, the various embodiments described may be used without the aid 
of an assistant's handle, or alternatively may be used in conjunction with 
such a handle to provide increased control or maneuverability of the lens 
on the eye. 
Other features and advantages of the invention will become apparent from 
the following detailed description of the invention in conjunction with 
the accompanying drawings

DETAILED DESCRIPTION OF THE INVENTION 
Referring to FIG. 1, there is shown a sectional view of a lens arrangement 
10 mounted on a cornea 12 of an eye 14. Lens arrangement 10 includes a 
frusto-conically shaped frame 16 which coaxially fixes a contact lens 
element 18 relative to an imaging lens 20, which together comprise an 
indirect ophthalmoscopy contact lens arrangement for creating a real 
aerial image of a structure in the eye anterior to the cornea of the 
examined eye. Contact lens element 18 has a concave posterior surface 22 
and a convex anterior surface 24. Concave posterior surface 22 has a shape 
substantially corresponding to the shape of an average cornea and 
therefore may have an apical radius of approximately 7.0 to 8.5 mm, and 
preferably may be approximately 7.7 to 7.8 mm. Posterior surface 22 may be 
spherical or aspherical and may be fitted on the cornea with the use of an 
interface solution 26 as is commonly known in the art. Referring 
additionally to FIG. 2 , posterior surface 22 preferably has a cord 
diameter d of approximately 9-13 mm and is most preferably about 11.7 mm. 
Anterior surface 24 may have an apical radius ranging from infinity for a 
planar surface to either a convex or concave radius of approximately 6.0 
mm., and may be either spherical or aspherical. Contact lens element 18 
has a peripheral region 28 which is connected with a flange 30 around its 
circumference. Flange 30 extends radically onto the sclera 32 of eye 14. 
Flange 30 has a posterior surface 34 which has a different curvature from 
that of posterior surface 22 of contact lens element 18, and more 
specifically, posterior surface 34 of flange 30 has a curvature 
substantially corresponding to the curvature of an average sclera of an 
eye, for example, a 12 mm. radius. Consequently, the curvature of the 
posterior surface 34 of flange 30 is substantially flatter than the 
curvature of the posterior surface 22 of contact lens element 18, and as 
such the lens device tends to be stabilized and centered over the cornea 
of the eye. Flange 30 has an anterior surface 35 that may have a slope or 
curvature that provides an adequate thickness of approximately 1.5 mm. to 
flange 30, thereby providing substantiality and strength to this 
component. Posterior surface 34 of flange 30 has a outside cord diameter D 
which may range from approximately 15 mm to approximately 20 mm, and is 
preferably 16 to 17 mm in diameter. Contact lens element 18 is fixed, for 
example, by a screw connection (not shown) to the smaller diameter end of 
frusto-conical frame 16. Imaging lens 20 is fixed at the larger opening 
end of frusto-conical frame 16 between a shoulder 36 and an o-ring 38, or 
by other conventional fastening means. Imaging lens 20 is coaxially fixed 
relative to contact lens element 18 and is preferably biconvex with a 
power which may be as high as 150 to 170 diopters. Imaging lens 20 is 
spaced from and cooperates in a known manner with contact lens element 18 
for capturing light rays exiting the eye through the cornea and passing 
through contact lens element 18. Imaging lens 20 focuses such light rays 
to create a real image of the retina and vitreous anterior to the cornea, 
and preferably anterior of imaging lens 20. An indirect ophthalmoscopy 
lens system of this type which includes a contact lens element and one or 
more imaging lenses is known in the art and is described in detail, for 
example, in my prior U.S. Pat. No. 5,046,836, which is incorporated herein 
by reference. 
FIG. 2 is a plan view of contact lens element 18 and flange 30. In this 
embodiment, contact lens element 18 and flange 30 are made of the same 
optically transparent material and are integrally connected with one 
another in peripheral region 28 as a single unit. As can be seen in FIG. 
2, flange 30 has four evenly spaced recesses 40 each of which has an 
opening at the outer periphery 42 of flange 30 and extend radially 
inwardly toward contact lens element 18. The circumferential extent C of 
the opening of each recess 40 at the outer periphery 42 may be from about 
4 to about 8 mm, and is preferably about 6.75 mm, and each recess 40 
extends radially inwardly from an imaginary extension of the outer 
periphery 42, shown by a dotted line in FIG. 2 in the lower right-hand 
recess, by a distance "r" of about 1 to about 5.5 mm, and is preferably 
about 2.15 mm. In general, the recess or recesses are sized to accommodate 
known dimensions of current surgical tools which penetrate the sclera 
during vitreoretinal surgery. 
FIGS. 3 and 4 illustrate an embodiment modified from that of FIGS. 1 and 2 
wherein a flange 30' constitutes a separate component from that of contact 
lens element 18' which is fixed in frame 16' coaxially with imaging lens 
20. Flange 30', which is shown in plan view in FIG. 4, may be made of 
metal or any other suitable material which is biocompatible with the eye. 
In this embodiment, contact lens element 18' presents a circumferential 
edge 19 which has a diameter the same or just slightly less than the inner 
diameter of flange 30' so that contact lens element 18' can be slidably 
received within flange 30' for stabilizing the indirect ophthalmoscopy 
lens system 10' relative to eye 14. Recesses 40 in flange 30' are sized 
the same as described in connection with FIG. 2. Flange 30' thus operates 
in the same manner as flange 30 in FIG. 2 to stabilize the lens system 10' 
relative to the eye. Flange 30' may be designed to accommodate lens types 
presently used in vitreoretinal surgery, thus providing a means by which 
such existing lenses may be used advantageously without the need for a 
handle or suture down ring. 
FIG. 5 shows an embodiment of the invention wherein a flange 30" is 
integrally connected with a direct ophthalmoscopy lens 43. Direct 
ophthalmoscopy lens 43 has a concave posterior surface 44 which has a 
shape adapted to fit an average cornea and a plano anterior surface 46. 
Direct ophthalmoscopy lens 43 operates in a known manner for creating a 
virtual image of the patient's retina which can be viewed through a 
microscope by an observer. In accordance with the invention, flange 30", 
which is connected to direct ophthalmoscopy lens 43 in a peripheral region 
48, has 4 recesses like those illustrated in FIG. 2, spaced apart evenly 
around the circumference of the flange for accommodating surgical tools or 
instruments inserted into the eye during surgery. Although FIG. 5 
illustrates direct ophthalmoscopy lens 43 and flange 30" as constituting a 
single component made of the same optically transparent material, it is 
possible for flange 30" and direct ophthalmoscopy lens 43 to be separate 
components. In such a case, the flange would releaseably receive the 
direct ophthalmoscopy lens for stabilizing the lens relative to the eye 
during a surgical or diagnostic procedure much the same as described above 
in connection with the embodiment of FIGS. 3 and 4. 
FIGS. 6 and 7 show a contact lens arrangement relating to an embodiment of 
the invention wherein a flange 30'" incorporates vacuum ports 52 
communicating with the posterior surface 34' of the flange to further 
enhance the stable positioning of a slidably received direct 
ophthalmoscopy contact lens element 43' through vacuum suction to the 
sclera of a patient's eye 14. A vacuum port may be located on one or more 
of the structural portions of the flange between the recesses 40, and may 
be designed as a channel at the posterior surface or hole passing through 
the body of the flange from posterior surface 34' to anterior surface 35'. 
At anterior surface 35' a small diameter flexible hose 56, such as 
surgical silicone hose, may be adapted to the vacuum ports 52 and 
connected to a vacuum source 58 such as a metered vacuum pump squeeze bulb 
or syringe operated by the physician's assistant. 
Various modifications may be made to the lens arrangements described above 
without departing from the spirit and scope of the invention. For example, 
the flange surrounding the contact lens element may incorporate a bridge 
49 to form fully enclosed openings 50 as shown in FIG. 8. In a further 
modification, bridge 49 may incorporate a vacuum channel extending partly 
or fully around the circumference of the lens for the same purpose as 
described in the embodiment of FIGS. 6 and 7. In a further modification 
the flange may have less than four recesses or openings. Specifically, it 
is possible for the flange to have one recess, or alternatively three 
recesses or openings spaced apart at the 11 o'clock, 2 o'clock and 4 or 8 
o'clock positions, which are incision positions that a surgeon may 
typically utilize for inserting surgical tools or instrumentation into the 
eye during a surgical procedure. Further, the size of the recesses or 
openings may vary from the dimensions mentioned above, particularly in the 
circumferential extent of the recess or opening. 
It should be apparent that other changes and modifications may be made 
without departing from the invention in its broader aspects, and the 
invention, therefore, as defined in the appendant claims is intended to 
cover all such changes and modifications that fall within the true spirit 
of the invention.