US2881500A - Corneal clamp - Google Patents

Description

Aprll 14, 1959 c. w. FURNESS CORNEAL CLAMP Filed July 3, 1958 IN VEN TOR. 4. Pam 55 AWE/767.5

United rates Patent 2,ss1,s00

CORNEAL CLAMP Charles W. Furness, Silver Spring, Md., assignor to the United States of America as represented by the Secretary of the Army Application July 3, 1958, Serial No. 746,573

1 Claim. (Cl. 24-243) (Granted under Title 35, U. S. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.

The present invention relates to a clamp for holding corneas which are preserved by dehydration for future use.

The new system used to preserve corneas by dehydration has brought about one of the greatest advances in ophthalmology since the fresh corneal transplant first took place. Now it is possible to store corneas indefinitely and stockpile them for future use. However, when some of the corneas that have been preserved are removed from their storage containers there is a wrinkling on the corneal surface. During the dehydration process, the corneas sometimes roll up or fold with two or more creases, such as a piece of paper would have after having been folded. When the corneas that do not roll up or fold are rehydrated, they have a smooth epithelium surface; whereas, the ones that fold have a ridge where the fold occurred. This ridge makes it very difficult to remove a lamellar graft from the cornea and keep the graft the same thickness throughout.

An object of the present invention is to hold the cornea in its original shape and curve, thereby preventing the cornea from rolling up or folding during the dehydration process.

Another object is to provide for the draining of the moisture from the endothelium side of the cornea during the dehydration process while the cornea is being held in the clamp.

A further object is to provide a clamp of simple and inexpensive construction easily and conveniently operated.

Further objects and a more complete understanding of the invention may be obtained by referring to the following description and claim taken in conjunction with the accompanying drawings which show an illustrative embodiment of the construction forming the basis of the invention and in which- Fig. 1 shows a top view of the clamp in an open position;

Fig. 2 shows a top view of the clamp folded so that the left end is immediately above and centered over the right end;

Fig. 3 is an elevational view of Fig. 2 partly in section; and

Fig. 4 is an elevational view partly in section of the device in its clamped position. I

Referring to Figs. 1, 2, and 3, the clamp is formed from a single strip of materialvl having a supporting end 2 and securing end 3. Supporting end 2 has perforated portion 4 curved upwardly and formed in curvature to give natural support to the cornea to be preserved. Securing end 3 has a circular aperture 5 and beveled surface 6. The diameter of aperture 5 is slightly less than that of the cornea to be preserved, and the angle of the "ice 2 beveled surface 6 conforms to that of the surface of perforated portion 4 with which it cooperates in holding the cornea when in the clamped position (Fig. 4). Holes 7 are of slightly smaller diameter than screw 8. Screw 8 (Fig. 4) cuts its own threads in the sides of holes 7 and is used in holding the device in the clamped position.

The device operates and is used as follows: Strip 1 is folded over so that securing end 3 is centered above supporting end 2. After the cornea which is to be preserved is removed from the eye, it is placed on perforated portion 4, securing end 2 is lowered so that the cornea projects through aperture 5, and beveled surface 6 fits around the cornea on perforated portion 4. Screw 8 is inserted and adjusted to hold the cornea firmly but not too tightly. Perforated portion 4 permits the moisture from the endothelium side of the cornea to escape during the dehydration process. The clamp with the cornea in position is placed in a container with glycerin, dehydrated, and retained in the container for future use. When the cornea is needed for a transplant, the container which houses the dehydrated cornea and clamp is opened, and the clamp with the cornea in position is removed from the container. The clamp with the cornea is placed in an antibiotic solution and the cornea is rehydrated. The lamellar graft is removed from the cornea by the surgeon while an assistant holds the clamp with the cornea in position.

In one embodiment of the invention, a model was made of sheet plastic material 1.5 mm. thick with pettinent dimensions as follows: Length, mm.; diameter of supporting end 2, 18 mm.; perforated portion 4, 10 perforations, each 2 mm. in diameter equally spaced; perforated portion 4 of spherical curvature with a 6.7 mm. radius; aperture 5 of circular configuration with a diameter of 10 mm.; screw 8, stainless steel, 4-40 X Although this model is suitable for an adult human cornea, the dimensions may be varied for use with corneas of children and animals; and if the clamp is used for holding fragile material other than corneas, both the configuration of the perforated portion and the securing end and the dimensions may be varied to accommodate the object desired to be held or supported.

I claim:

A clamp for holding a cornea comprising a strip of material having adjacent one end a raised portion of uniform curvature projecting in a direction normal to the plane of the strip and of circular configuration in hori zontal section and adjacent the other end a circular aperture, said strip of material folded over at a point between the ends thereof so that said aperture is immediately above and centered over said raised portion, said raised portion having a plurality of perforations and said aperture having a beveled edge around its perimeter to conform to the curvature of said raised portion, and means for adjusting the degree of protrusion of said raised portion through said aperture, whereby a cornea is given support by said raised portion when placed thereon and is held in position thereon by the beveled edge around the perimeter of said aperture, said perforations in said raised portion permitting flow of liquid from the cornea.

References Cited in the file of this patent UNITED STATES PATENTS 468,341 Harris Feb. 9, 1892 963,085 Smith July 5, 1910 2,420,142 Levin May 6, 1947 FOREIGN PATENTS 85,410 Germany Feb. 13, 1896

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