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NOTES, CASES, INSTRUMENTS SIMPLIFIED DOUBLE-EDGE KNIFE* A.
BENEDICT RIZZUTI,
M.D.
Brooklyn, New York Within the past several years both scleral resection for retinal detachment and keratoplasties, penetrating and lamellar, have be come more readily accepted by a greater number of surgeons. T o simplify further the surgical tech niques, and for expediency, a special simpli fied double-edge knife was devised.* T h e body of the knife measures 3.75 inches in length, is easily held by the fingers, and rests comfortably in the palm of the hand. A screw mechanism on the body regulates the desired amount of mm. separation of the cutting edges. Measurement is made directly on a caliper. T h e cutting edges consist of two small, sharp, rounded, removable blades that can be easily inserted and fastened in a set position by two individual thumb screws. The blade edge is shaped similar to a Gill knife which prevents any undue perforation of the cornea or sclera. It becomes quite simple to cut either along a straight line (keratoplasty) or on a deep curve (scleral resection). T h e removable knife blades can either be sharp ened or simply replaced by new ones at a minimal cost. T h e knife was found to be particularly useful in mapping out and cutting a three or four-mm. scleral strip in lamellar scleral resection. It has also been used for square or rectangular penetrating or lamellar corneal grafting. I n circular lamellar keratoplasties one knife edge can be inserted for the corneal dissection when removing the diseased re cipient corneal tissue. Its use has also been found practical for marking the proper site on the sclera, in muscle surgery, for the in sertion of sutures. I n conclusion, this simple double-bladed * Used in the Corneal Clinic, Brooklyn Eye and Ear Hospital. t This instrument may be obtained from the Storz Instrument Company, 4570 Audubon Avenue, St. Louis 10, Missouri.
Fig. 1 (Rizzuti). Simplified double-edge knife for use in scleral resection or keratoplasties
Fig. 2 (Rizzuti). Knife, showing removable round-edge blades. knife possesses the distinct advantages of be ing light, easy to handle, able in making a quick change of obtainable sharp blades and versatile in its use in ophthalmic surgery. 160 Henry Street (1). MODIFICATION OF TUDOR-THOMAS METAL STAND* P . K. BASU,* D . O . M . S . , AND H.
L. O R M S B Y ,
M.D.
Toronto, Ontario T h e Tudor-Thomas metal stand has been modified to facilitate the introduction of the suture attached to the optic nerve of the donor eye. A vertical slit has been sawed through the body of the stand to meet the hollow central core. T h e suture can be drawn through this * From the Department of Ophthalmology, Fac ulty of Medicine, University of Toronto. t Department of Ophthalmology, Ramakrishna Mission Sevashrama, Vrindaban, U. P., India.