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A New Disposable Corneal Trephine*
NOTES, CASES, INSTRUMENTS
923
A N E W DISPOSABLE CORNEAL T R E P H I N E * M. MARTINEZ,
M.D.
AND
IL M. KATZIN,
M.D.
New York Undoubtedly perfection in surgical sections is a major factor in the proper healing of wounds. In corneal surgery this factor is even more important because of the extreme fineness of the structures and the unusual characteristics of the tissue itself. There is no doubt that a clean regular section, in perfect apposition, will have a better chance of healing without complications than a section which is irregular and poorly apposed. In corneal grafting, where the healing process is delayed by so many factors, the perfection of trephination is perhaps one of the most important reasons for the fate of the graft and the optical result. Round corneal grafts have been proved by the experience of many years to be the best type of surgical approach for replacing pathologic corneal tissue. The obvious reason is the technical ease of performing this type of shape versus square, triangular or parallelogram-shaped grafts, which have been attempted in the past and have now been relegated to unusual situations for very special cases. Our present technical problems with round grafting are minimal and our present instrumentation is efficient and practical in many respects, but the cost is still high and the replacement of a good trephine is sometimes difficult and time consuming. The cutting edge of our present trephines is sharp enough to accomplish their purpose without deforming the corneal dome too much, and the light pressure required to section the corneal tissue in itself avoids * From the Eye-Bank for Sight Restoration, Inc. This instrument is manufactured by Storz Surgical Instruments, 629 Park Avenue, New York, NewYork 10021.
Fig. 1 (Martinez and Katzin). The new disposable corneal trephine. major imperfections or complications during the trephination. We have to remember that the most important feature of any trephine is the sharpness and efficiency of the cutting edge; this in itself is perhaps the first feature of which the surgeon has to be aware. The other features, as depth gauges or moving parts, are only accessories which add a certain degree of versatility or comfort to the instrument but they are not in any way as important as the sharpness of the instrument itself. For several years, we have been contemplating the possibility of using a razor blade edge to manufacture the cutting edge of a trephine. Years ago, the fact that all the razor blades on the market were made of brittle, highly tempered steel did not permit tis to transform a straight blade into a circular cutting device without breaking the steel. With the introduction of stainless steel razor blades, the possibility of manufacturing a perfectly round cutting instrument has become a reality and we have been fully successful in shaping a flat band, 3 mm in width and of varying lengths, of this type of new razor blade into a perfectly round cutting device. The flexibility and softness of the stainless steel, used at present for commercial razor blades, permits the shaping of curves from 6 mm in diameter to any size above this without breaking the band or inflicting
NOTES, CASES, INSTRUMENTS
924
any stress on the cutting edge which will damage its cutting properties. In this manner we have produced, in our own laboratory, perfect and extremely sharp corneal trephines using commercial steel blades which have proven to have the following outstanding features: 1. Ideal simplicity of manufacturing. 2. Unusual sharpness, superior to any other trephine we know. 3. Even thickness of the blade above the cutting edge. 4. Ease in manufacturing in-between sizes. 5. A rust-proof instrument. 6. Low cost manufacturing which makes the instrument disposable. 210 East 64th Street (10021). AC KNOWLEDGM ENT
We wish to thank Dr. R. Townley Paton for his advice and help during the construction of this instrument.
primary optic vesicle to disappear. Aptez felt that the cysts were remnants of the pupillary membrane, while Fuchs noted that cysts might possibly arise from detached flocculi at the pupillary margin. Hadlund noted that most authors concluded that the cysts were congenital in origin, asymptomatic in most cases and that no treatment was necessary. Gross pathologic examination shows that these cysts vary in color, being yellowish to brownish and are ovoid to circular in shape. T h e y are known as flocculi, granula, villositates or grape-seed bodies. Microscopically, they are usually collapsed when examined but appear to be composed chiefly of pigment granules, with walls several layers thick. Boch, Lewis and Evans noted, verified and recorded that the cyst walls are several layers thick, with cells similiar to those in the posterior epithelial cells of the iris. CASE
SURGICAL MANAGEMENT O F A FREE-FLOATING IRIS CYST I N T H E ANTERIOR CHAMBER ALBERT C. ESPOSITO,
M.D.
Huntington, West Virginia That a free-floating iris cyst in the anterior chamber is not an usual occurrence is noted by Duke-Elder, Lewis, Evans and others. Of special note is a lack of specific details as to a possible technique of management of this entity. A review of the literature reveals that Businelli, in 1868, recorded the first case with this finding. Since that time sporadic cases have been reported. Various theories as to the causative mechanism for the cyst's formation have been advanced. Mann felt that their origin was from the marginal sinus prior to the completion of the neural ectoderm around the optic cup, as this was the last cavity of the
REPORT
Mrs. C. K. W., a 27-year-old white woman, was seen on August 18, 1961, because of periodic periods of sudden blindness of the left eye. There was a history of trauma to the left eye 18 years previously. She noted that four years ago a dark spot appeared at the 6-o'clock position of her left eye and, shortly thereafter, she began to notice that this spot floated about. Examination revealed a normal external eye, conjunctiva and cornea. The pupils were round and equal, reacting readily to light and accommodation. A small, bluish, ovoid object 2 by 4 mm in size was seen in the anterior chamber (fig. 1 ). With changes in the position of the patient's head, the object slowly moved and floated up along the iris to the pupillary area. By oblique and slitlamp examination, it was translucent and transparent, and appeared to be an iris cyst floating in the anterior chamber. This cyst was observed at different intervals during the day and its movement was readily visible. The iris was searched with the slitlamp but no additional cysts were noted, nor was the location of origin of the one free in the anterior chamber noted. Use of a Goldmann goniolens did not reveal a stalk or area of origin. The chamber angles were normal in appearance. In view of the size of the cyst and the presenting symptoms, surgical removal was suggested. In order to keep the pupils constricted prior to surgery, 2% pilocarpine drops (tid) were ordered. Surgery was performed under local anesthesia on August 21, 1961.
923
A N E W DISPOSABLE CORNEAL T R E P H I N E * M. MARTINEZ,
M.D.
AND
IL M. KATZIN,
M.D.
New York Undoubtedly perfection in surgical sections is a major factor in the proper healing of wounds. In corneal surgery this factor is even more important because of the extreme fineness of the structures and the unusual characteristics of the tissue itself. There is no doubt that a clean regular section, in perfect apposition, will have a better chance of healing without complications than a section which is irregular and poorly apposed. In corneal grafting, where the healing process is delayed by so many factors, the perfection of trephination is perhaps one of the most important reasons for the fate of the graft and the optical result. Round corneal grafts have been proved by the experience of many years to be the best type of surgical approach for replacing pathologic corneal tissue. The obvious reason is the technical ease of performing this type of shape versus square, triangular or parallelogram-shaped grafts, which have been attempted in the past and have now been relegated to unusual situations for very special cases. Our present technical problems with round grafting are minimal and our present instrumentation is efficient and practical in many respects, but the cost is still high and the replacement of a good trephine is sometimes difficult and time consuming. The cutting edge of our present trephines is sharp enough to accomplish their purpose without deforming the corneal dome too much, and the light pressure required to section the corneal tissue in itself avoids * From the Eye-Bank for Sight Restoration, Inc. This instrument is manufactured by Storz Surgical Instruments, 629 Park Avenue, New York, NewYork 10021.
Fig. 1 (Martinez and Katzin). The new disposable corneal trephine. major imperfections or complications during the trephination. We have to remember that the most important feature of any trephine is the sharpness and efficiency of the cutting edge; this in itself is perhaps the first feature of which the surgeon has to be aware. The other features, as depth gauges or moving parts, are only accessories which add a certain degree of versatility or comfort to the instrument but they are not in any way as important as the sharpness of the instrument itself. For several years, we have been contemplating the possibility of using a razor blade edge to manufacture the cutting edge of a trephine. Years ago, the fact that all the razor blades on the market were made of brittle, highly tempered steel did not permit tis to transform a straight blade into a circular cutting device without breaking the steel. With the introduction of stainless steel razor blades, the possibility of manufacturing a perfectly round cutting instrument has become a reality and we have been fully successful in shaping a flat band, 3 mm in width and of varying lengths, of this type of new razor blade into a perfectly round cutting device. The flexibility and softness of the stainless steel, used at present for commercial razor blades, permits the shaping of curves from 6 mm in diameter to any size above this without breaking the band or inflicting
NOTES, CASES, INSTRUMENTS
924
any stress on the cutting edge which will damage its cutting properties. In this manner we have produced, in our own laboratory, perfect and extremely sharp corneal trephines using commercial steel blades which have proven to have the following outstanding features: 1. Ideal simplicity of manufacturing. 2. Unusual sharpness, superior to any other trephine we know. 3. Even thickness of the blade above the cutting edge. 4. Ease in manufacturing in-between sizes. 5. A rust-proof instrument. 6. Low cost manufacturing which makes the instrument disposable. 210 East 64th Street (10021). AC KNOWLEDGM ENT
We wish to thank Dr. R. Townley Paton for his advice and help during the construction of this instrument.
primary optic vesicle to disappear. Aptez felt that the cysts were remnants of the pupillary membrane, while Fuchs noted that cysts might possibly arise from detached flocculi at the pupillary margin. Hadlund noted that most authors concluded that the cysts were congenital in origin, asymptomatic in most cases and that no treatment was necessary. Gross pathologic examination shows that these cysts vary in color, being yellowish to brownish and are ovoid to circular in shape. T h e y are known as flocculi, granula, villositates or grape-seed bodies. Microscopically, they are usually collapsed when examined but appear to be composed chiefly of pigment granules, with walls several layers thick. Boch, Lewis and Evans noted, verified and recorded that the cyst walls are several layers thick, with cells similiar to those in the posterior epithelial cells of the iris. CASE
SURGICAL MANAGEMENT O F A FREE-FLOATING IRIS CYST I N T H E ANTERIOR CHAMBER ALBERT C. ESPOSITO,
M.D.
Huntington, West Virginia That a free-floating iris cyst in the anterior chamber is not an usual occurrence is noted by Duke-Elder, Lewis, Evans and others. Of special note is a lack of specific details as to a possible technique of management of this entity. A review of the literature reveals that Businelli, in 1868, recorded the first case with this finding. Since that time sporadic cases have been reported. Various theories as to the causative mechanism for the cyst's formation have been advanced. Mann felt that their origin was from the marginal sinus prior to the completion of the neural ectoderm around the optic cup, as this was the last cavity of the
REPORT
Mrs. C. K. W., a 27-year-old white woman, was seen on August 18, 1961, because of periodic periods of sudden blindness of the left eye. There was a history of trauma to the left eye 18 years previously. She noted that four years ago a dark spot appeared at the 6-o'clock position of her left eye and, shortly thereafter, she began to notice that this spot floated about. Examination revealed a normal external eye, conjunctiva and cornea. The pupils were round and equal, reacting readily to light and accommodation. A small, bluish, ovoid object 2 by 4 mm in size was seen in the anterior chamber (fig. 1 ). With changes in the position of the patient's head, the object slowly moved and floated up along the iris to the pupillary area. By oblique and slitlamp examination, it was translucent and transparent, and appeared to be an iris cyst floating in the anterior chamber. This cyst was observed at different intervals during the day and its movement was readily visible. The iris was searched with the slitlamp but no additional cysts were noted, nor was the location of origin of the one free in the anterior chamber noted. Use of a Goldmann goniolens did not reveal a stalk or area of origin. The chamber angles were normal in appearance. In view of the size of the cyst and the presenting symptoms, surgical removal was suggested. In order to keep the pupils constricted prior to surgery, 2% pilocarpine drops (tid) were ordered. Surgery was performed under local anesthesia on August 21, 1961.