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Spectacles for Microsurgery
AMERICAN JOURNAL OF OPHTHALMOLOGY
336
AUGUST, 1974
TABLE 1
TABLE 2
REFRACTIVE ERROR ESTIMATE, VERTEX DISTANCE 0 MM
REFRACTIVE ERROR ESTIMATE, VERTEX DISTANCE 10 MM
Lenses Used
VD, mm
+ 16.00D
+20.00 D
Measured VD, mm
0 4 6 8 10 12 14 16 18 20 22 24 26
+ 14.00D +14.83 + 15.28 +15.77 +16.28 +16.83 +17.41 +18.04 +18.72 + 19.44 +20.23 +21.08 +22.01
+ 18.00D + 19.40 +20.18 +21.03 +21.95 +22.96 +24.06 +25.28 +26.63 +28.13 +29.80 +31.69 +33.83
0 4 6 8 10 12 14 16 18 20 22 24 26
Measured
the operatin g room. Listed in Table 1 are values of refractive error estimate using + 16 D and + 20 D trial case lenses for different vertex distances above the eye. These two lenses, with overlapping refrac tive ranges, cover a large range of correc tions. A 2.0 D working distance correction has been subtracted from all values. The values given in Table 1 are corrected to the corneal plane—as one might do when con sidering a contact lens correction. Comparable values may be computed for other trial case lenses. Vertex distance should be measured to the nearest millimeter (or half millimeter if possible). If spectacle corrections are used instead of contact lenses, i.e., vertex distance is greater than 0 mm, a different vertex distance correction is applied to the retinoscopic determination. For example, in Table 2 a vertex distance of 10 mm has been substituted. There are alternative approaches useful in minimizing error in these cases, for instance, using a known-power contact lens (say, + 20 D) and retinoscoping over this cor rection. However, the approach suggested, using a single high-plus lens and measuring vertex distance at retinoscopic neutrality, is relatively simple, requires no special equip ment, and does not alter corneal astigmatism.
Lenses Used + 16.00D
+20.00 D
+12.28D + 12.92 + 13.26 +13.62 + 14.00 +14.40 + 14.83 + 15.28 +15.77 +16.28 +16.83 +17.41 +18.04
+ 15.25D +16.24 +16.79 +17.37 +18.00 +18.67 +19.40 +20.18 +21.03 +21.95 +22.96 +24.06 +25.28
SUMMARY
Retinoscopy can be performed rapidly in the anesthetized infant by merely adjusting a single high-power convex lens up and down above the eye of the child and having an assistant measure the vertex distance when the lens is held at the point of motion re versal or neutralization in each of the two major meridians. A working distance of 0.5 meter is used, and a + 16 D and a + 20 D lens cover a large range of correction. REFERENCE
1. Enoch, J. M.: The fitting of hydrophilic (soft) contact lenses to infants and young children. 1. Mensuration data on aphakic eyes of children born with congenital cataracts. Contact Lens Med. Bull. 5 :No. 3-4, 36,1972.
SPECTACLES FOR MICROSURGERY OTTO H.
JUNGSCHAFFER,
M.D.
North Hollywood, California
Better and more comfortable viewing through a microscope is obtained without glasses, yet the presbyopic surgeon still needs his correction. Reprint requests to Otto H. Jungschaffer, M.D., 12840 Riverside Dr., North Hollywood, CA 91607.
NOTES, CASES, INSTRUMENTS
VOL. 78, NO. 2
Figure (Jungschaffer). Spectacles in position. A modification of half glasses has become indispensable to me for microsurgery.* These glasses rest at the end of the nose and leave the eyes unobstructed for the microscope (Figure). This is achieved by extending the nose pieces 35 to 45 mm and bending them upward so that they rest on the bridge of the nose. The temple pieces are lengthened for a secure fit. SUMMARY
Half glasses for microsurgery are posi tioned at the end of the nose by extend ing the nose pieces 35 to 45 mm and bend ing them upward so they rest on the bridge of the nose. The temples are lengthened to obtain a secure fit. * The glasses were made by Leonard Optical Company, Panorama City, California. P R E V E N T I O N O F SCLERAL COLLAPSE DURING VITRECTOMY THOMAS O.
WOOD,
M.D.
Memphis, Tennessee Vitrectomy after vitreous loss during in traocular surgery has been accepted as a From the University of Tennessee College of Medicine, Department of Ophthalmology, Memphis, Tennessee. Reprint requests to Thomas O. Wood, M.D., Department of Ophthalmology, 858 Madison Ave., Memphis, TN 38103.
337
Figure (Wood). Four Dacron sutures sewn through the superficial sclera and drawn over den tal rolls to create an upward and outward pull on the globe. Each suture is exerting an equal amount of force. A lateral canthotomy has been cut. useful procedure in lessening the early and late complications of vitreous loss. Many methods have been described for accomplish ing the same goal, which is removal of solid vitreous humor from the anterior chamber and wound, without disturbing the retina.1"5 The Flieringa ring has been used for many years to prevent collapse of the sclera during vitrectomy. However, after the globe has been opened, it is frequently difficult to suture the ring in place without causing further trauma. An alternative is scleral sutures.2 Prevention of scleral collapse during vit rectomy can be accomplished by placing scleral sutures 3 to 4 mm posterior to the corneoscleral limbus in each quadrant of the globe, and carefully attaching the suture to the drape (Figure). Each suture should create an equal upward and outward pull on the globe. For this procedure 5-0 Dacron with a spatula needle is used. In prominent eyes the sutures should be draped over a dry dental roll. The surgeon should make sure that none of the sutures are exerting too great a pull, thereby avoiding distortion of the globe. Once these sutures are in place, the surgeon may proceed with a vitrectomy without collapse of the sclera. This tech nique is useful in keratoplasty, corneal per-
336
AUGUST, 1974
TABLE 1
TABLE 2
REFRACTIVE ERROR ESTIMATE, VERTEX DISTANCE 0 MM
REFRACTIVE ERROR ESTIMATE, VERTEX DISTANCE 10 MM
Lenses Used
VD, mm
+ 16.00D
+20.00 D
Measured VD, mm
0 4 6 8 10 12 14 16 18 20 22 24 26
+ 14.00D +14.83 + 15.28 +15.77 +16.28 +16.83 +17.41 +18.04 +18.72 + 19.44 +20.23 +21.08 +22.01
+ 18.00D + 19.40 +20.18 +21.03 +21.95 +22.96 +24.06 +25.28 +26.63 +28.13 +29.80 +31.69 +33.83
0 4 6 8 10 12 14 16 18 20 22 24 26
Measured
the operatin g room. Listed in Table 1 are values of refractive error estimate using + 16 D and + 20 D trial case lenses for different vertex distances above the eye. These two lenses, with overlapping refrac tive ranges, cover a large range of correc tions. A 2.0 D working distance correction has been subtracted from all values. The values given in Table 1 are corrected to the corneal plane—as one might do when con sidering a contact lens correction. Comparable values may be computed for other trial case lenses. Vertex distance should be measured to the nearest millimeter (or half millimeter if possible). If spectacle corrections are used instead of contact lenses, i.e., vertex distance is greater than 0 mm, a different vertex distance correction is applied to the retinoscopic determination. For example, in Table 2 a vertex distance of 10 mm has been substituted. There are alternative approaches useful in minimizing error in these cases, for instance, using a known-power contact lens (say, + 20 D) and retinoscoping over this cor rection. However, the approach suggested, using a single high-plus lens and measuring vertex distance at retinoscopic neutrality, is relatively simple, requires no special equip ment, and does not alter corneal astigmatism.
Lenses Used + 16.00D
+20.00 D
+12.28D + 12.92 + 13.26 +13.62 + 14.00 +14.40 + 14.83 + 15.28 +15.77 +16.28 +16.83 +17.41 +18.04
+ 15.25D +16.24 +16.79 +17.37 +18.00 +18.67 +19.40 +20.18 +21.03 +21.95 +22.96 +24.06 +25.28
SUMMARY
Retinoscopy can be performed rapidly in the anesthetized infant by merely adjusting a single high-power convex lens up and down above the eye of the child and having an assistant measure the vertex distance when the lens is held at the point of motion re versal or neutralization in each of the two major meridians. A working distance of 0.5 meter is used, and a + 16 D and a + 20 D lens cover a large range of correction. REFERENCE
1. Enoch, J. M.: The fitting of hydrophilic (soft) contact lenses to infants and young children. 1. Mensuration data on aphakic eyes of children born with congenital cataracts. Contact Lens Med. Bull. 5 :No. 3-4, 36,1972.
SPECTACLES FOR MICROSURGERY OTTO H.
JUNGSCHAFFER,
M.D.
North Hollywood, California
Better and more comfortable viewing through a microscope is obtained without glasses, yet the presbyopic surgeon still needs his correction. Reprint requests to Otto H. Jungschaffer, M.D., 12840 Riverside Dr., North Hollywood, CA 91607.
NOTES, CASES, INSTRUMENTS
VOL. 78, NO. 2
Figure (Jungschaffer). Spectacles in position. A modification of half glasses has become indispensable to me for microsurgery.* These glasses rest at the end of the nose and leave the eyes unobstructed for the microscope (Figure). This is achieved by extending the nose pieces 35 to 45 mm and bending them upward so that they rest on the bridge of the nose. The temple pieces are lengthened for a secure fit. SUMMARY
Half glasses for microsurgery are posi tioned at the end of the nose by extend ing the nose pieces 35 to 45 mm and bend ing them upward so they rest on the bridge of the nose. The temples are lengthened to obtain a secure fit. * The glasses were made by Leonard Optical Company, Panorama City, California. P R E V E N T I O N O F SCLERAL COLLAPSE DURING VITRECTOMY THOMAS O.
WOOD,
M.D.
Memphis, Tennessee Vitrectomy after vitreous loss during in traocular surgery has been accepted as a From the University of Tennessee College of Medicine, Department of Ophthalmology, Memphis, Tennessee. Reprint requests to Thomas O. Wood, M.D., Department of Ophthalmology, 858 Madison Ave., Memphis, TN 38103.
337
Figure (Wood). Four Dacron sutures sewn through the superficial sclera and drawn over den tal rolls to create an upward and outward pull on the globe. Each suture is exerting an equal amount of force. A lateral canthotomy has been cut. useful procedure in lessening the early and late complications of vitreous loss. Many methods have been described for accomplish ing the same goal, which is removal of solid vitreous humor from the anterior chamber and wound, without disturbing the retina.1"5 The Flieringa ring has been used for many years to prevent collapse of the sclera during vitrectomy. However, after the globe has been opened, it is frequently difficult to suture the ring in place without causing further trauma. An alternative is scleral sutures.2 Prevention of scleral collapse during vit rectomy can be accomplished by placing scleral sutures 3 to 4 mm posterior to the corneoscleral limbus in each quadrant of the globe, and carefully attaching the suture to the drape (Figure). Each suture should create an equal upward and outward pull on the globe. For this procedure 5-0 Dacron with a spatula needle is used. In prominent eyes the sutures should be draped over a dry dental roll. The surgeon should make sure that none of the sutures are exerting too great a pull, thereby avoiding distortion of the globe. Once these sutures are in place, the surgeon may proceed with a vitrectomy without collapse of the sclera. This tech nique is useful in keratoplasty, corneal per-