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A Self-Retaining Contact Lens for Slit-Lamp Examination of the Fundus and for Photocoagulation Treatment
VOL. 81, NO. 5
NOTES, CASES, INSTRUMENTS
irrigating forceps so as to allow controlled billowing out of the lens capsule for ac curate placement of the lens supports into the capsular fornices, cleaning off cataract and debris from the posterior lens cap sule, monitoring inflow of irrigation fluid when using a phacofragmenting and aspi rating device, and irrigation when using a vitreous cutting and aspirating device. SUMMARY
A solely mechanical foot-pedal operat ed valve for control of intraocular irriga tion provided independence from an as sistant and allowed accurate adjustment of flow. It was particularly useful during cataract aspiration, vitreous cutting, and intraocular lens implantation. A SELF-RETAINING CONTACT L E N S FOR SLIT-LAMP EXAMINATION O F T H E F U N D U S AND FOR PHOTOCOAGULATION TREATMENT J O H N G. S E B E S T Y E N , Boston,
M.D.
Massachusetts
A lens that neutralizes the refractive power of the cornea is needed during slit-lamp examination and laser photoco agulation treatment of the posterior pole. There are two categories of such lenses: the Hruby lens and the contact lens. The available contact lenses have to be held in place either by hand (Goldmann type lenses) or by suction. The suction-held lenses produce epithelial edema which, in case of prolonged examination or treat ment, makes visualization and photo graphing difficult. Both are physically
683
bulky, thus making their insertion awk ward and uncomfortable in eyes with narrow palpebral fissures and in deep-set eyes. One contact lens* obviates these prob lems and allows the examiner complete freedom of both hands for the operation of the slit lamp or the laser. The lens was fabricated from polymethylmethacrylate by turning on a radi us cutting lathe. It was an entirely corneal lens, with a diameter of 11 mm (Fig. 1). It had a highly polished piano front surface and an 8.5-mm radius posterior curve. The center thickness was 0.45 mm and the edge thickness was 2 mm. It weighed less than 150 mg. I applied the lens to the anesthetized cornea after moistening its concave surface with a small amount of methlycellulose (Fig. 2), affording a clear view of the posterior pole. When using 16 x magnification of the biomicroscope, I saw and treated an area of the fundus ranging from 6 to 10 disk diameters from the center of the macula in either direc tion by having the patient change his direction of gaze appropriately. Approximately 150 patients have been photocoagulated by using this contact lens. Corneal abrasion occurred in none of these patients and good quality fundus photographs were obtained almost imme diately after the conclusion of the treat ment.
This study was made possible by the Joslin Dia betes Foundation, Inc., Boston, Massachusetts. Reprint requests to John G. Sebestyen, M.D., 170 Pilgrim Rd., Boston, MA 02215. T h e lens is manufactured by E. Benson Hood, Surgical Laboratories, Inc., Duxbury, Massachusetts.
Fig. 1 (Sebestyen). Self-retaining contact lens for slit-lamp examination of the fundus and for laser treatment.
684
AMERICAN JOURNAL OF OPHTHALMOLOGY
MAY, 1976
lizing the instrument on the recipient eye, and the lower ridge containing the suc tion device that firmly holds the eye with pressure (10 to 15 mm Hg) and assures centration. The inner cone revolves and acts as the carrier for a slide mechanism with an attached disposable razor blade.* After each rotation, the blade is lowered a few thousandths of an inch by turning a screw (Fig. 1, A) and rotated again. Both sides of the incision could be viewed through the operating microscope. The diameter of the incision is precisely var ied from 8.5 to 2.0 mm by adjusting another screw (Fig. 1, B).
Fig. 2 (Sebestyen). Contact lens in position on patient's eye. SUMMARY
A self-retaining contact lens for slitlamp examination and photocoagulation treatment of the posterior fundus afford ed a wide-angle view of the retina and allowed freedom of both hands of the examiner. A NEW CORNEAL T R E P H I N E D A V I D M. L I E B E R M A N ,
M.D.
Brooklyn, New York
A new instrument* used in corneal transplantation comprises two cones, one revolving inside the other. The outer cone has two parts: the upper ridge held in the nondominant hand of the surgeon, stabiFrom the Methodist Hospital of Brooklyn, Brooklyn, New York. Reprint requests to David M. Lieberman, M.D., 9 Prospect Park West, Brooklyn, NY 11215. *AvaiIable from Storz Instrument Company, St. Louis, Missouri, and from the Keeler Instrument Company, London, England.
Figure (Lieberman). A new corneal trephine in cludes the outer ring (1), the inner ring (2), a screw adjusting the height of the razor blade fragment (A), and a screw that adjusts the diameter of the incision (8.5 to 2.0 mm) (B).
Two interchangeable cutters are in cluded: one inclines the razor blade at 20 degrees, suitable for lamellar grafts, and a second holds the razor blade vertically, suitable for keratoplasty in which the donor button has been "punched." This instrument can be effectively used only on whole eyes; it cannot be used to cut preserved corneas. The trephine cuts 360 degrees and full thickness of stroma. About 60 degrees of Descemet's membrane and endothelium are cut with the razor before adjusting upward; the remaining structures are more precisely cut with scissors.
NOTES, CASES, INSTRUMENTS
irrigating forceps so as to allow controlled billowing out of the lens capsule for ac curate placement of the lens supports into the capsular fornices, cleaning off cataract and debris from the posterior lens cap sule, monitoring inflow of irrigation fluid when using a phacofragmenting and aspi rating device, and irrigation when using a vitreous cutting and aspirating device. SUMMARY
A solely mechanical foot-pedal operat ed valve for control of intraocular irriga tion provided independence from an as sistant and allowed accurate adjustment of flow. It was particularly useful during cataract aspiration, vitreous cutting, and intraocular lens implantation. A SELF-RETAINING CONTACT L E N S FOR SLIT-LAMP EXAMINATION O F T H E F U N D U S AND FOR PHOTOCOAGULATION TREATMENT J O H N G. S E B E S T Y E N , Boston,
M.D.
Massachusetts
A lens that neutralizes the refractive power of the cornea is needed during slit-lamp examination and laser photoco agulation treatment of the posterior pole. There are two categories of such lenses: the Hruby lens and the contact lens. The available contact lenses have to be held in place either by hand (Goldmann type lenses) or by suction. The suction-held lenses produce epithelial edema which, in case of prolonged examination or treat ment, makes visualization and photo graphing difficult. Both are physically
683
bulky, thus making their insertion awk ward and uncomfortable in eyes with narrow palpebral fissures and in deep-set eyes. One contact lens* obviates these prob lems and allows the examiner complete freedom of both hands for the operation of the slit lamp or the laser. The lens was fabricated from polymethylmethacrylate by turning on a radi us cutting lathe. It was an entirely corneal lens, with a diameter of 11 mm (Fig. 1). It had a highly polished piano front surface and an 8.5-mm radius posterior curve. The center thickness was 0.45 mm and the edge thickness was 2 mm. It weighed less than 150 mg. I applied the lens to the anesthetized cornea after moistening its concave surface with a small amount of methlycellulose (Fig. 2), affording a clear view of the posterior pole. When using 16 x magnification of the biomicroscope, I saw and treated an area of the fundus ranging from 6 to 10 disk diameters from the center of the macula in either direc tion by having the patient change his direction of gaze appropriately. Approximately 150 patients have been photocoagulated by using this contact lens. Corneal abrasion occurred in none of these patients and good quality fundus photographs were obtained almost imme diately after the conclusion of the treat ment.
This study was made possible by the Joslin Dia betes Foundation, Inc., Boston, Massachusetts. Reprint requests to John G. Sebestyen, M.D., 170 Pilgrim Rd., Boston, MA 02215. T h e lens is manufactured by E. Benson Hood, Surgical Laboratories, Inc., Duxbury, Massachusetts.
Fig. 1 (Sebestyen). Self-retaining contact lens for slit-lamp examination of the fundus and for laser treatment.
684
AMERICAN JOURNAL OF OPHTHALMOLOGY
MAY, 1976
lizing the instrument on the recipient eye, and the lower ridge containing the suc tion device that firmly holds the eye with pressure (10 to 15 mm Hg) and assures centration. The inner cone revolves and acts as the carrier for a slide mechanism with an attached disposable razor blade.* After each rotation, the blade is lowered a few thousandths of an inch by turning a screw (Fig. 1, A) and rotated again. Both sides of the incision could be viewed through the operating microscope. The diameter of the incision is precisely var ied from 8.5 to 2.0 mm by adjusting another screw (Fig. 1, B).
Fig. 2 (Sebestyen). Contact lens in position on patient's eye. SUMMARY
A self-retaining contact lens for slitlamp examination and photocoagulation treatment of the posterior fundus afford ed a wide-angle view of the retina and allowed freedom of both hands of the examiner. A NEW CORNEAL T R E P H I N E D A V I D M. L I E B E R M A N ,
M.D.
Brooklyn, New York
A new instrument* used in corneal transplantation comprises two cones, one revolving inside the other. The outer cone has two parts: the upper ridge held in the nondominant hand of the surgeon, stabiFrom the Methodist Hospital of Brooklyn, Brooklyn, New York. Reprint requests to David M. Lieberman, M.D., 9 Prospect Park West, Brooklyn, NY 11215. *AvaiIable from Storz Instrument Company, St. Louis, Missouri, and from the Keeler Instrument Company, London, England.
Figure (Lieberman). A new corneal trephine in cludes the outer ring (1), the inner ring (2), a screw adjusting the height of the razor blade fragment (A), and a screw that adjusts the diameter of the incision (8.5 to 2.0 mm) (B).
Two interchangeable cutters are in cluded: one inclines the razor blade at 20 degrees, suitable for lamellar grafts, and a second holds the razor blade vertically, suitable for keratoplasty in which the donor button has been "punched." This instrument can be effectively used only on whole eyes; it cannot be used to cut preserved corneas. The trephine cuts 360 degrees and full thickness of stroma. About 60 degrees of Descemet's membrane and endothelium are cut with the razor before adjusting upward; the remaining structures are more precisely cut with scissors.