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Nd:YAG Laser Damage to Silicone Intraocular Lenses Confused With Pigment Deposits on Clinical Examination
526
October, 1994
AMERICAN JOURNAL OF OPHTHALMOLOGY
References
Fig. 2 (Miller). The remaining subincisional cortex is loosened after intraocular lens insertion by pulling the lens into the cortex with an iris manipulator and spinning the lens several times.
exclusively for several years. The procedure works best if a three-piece silicone intraocular lens is implanted, but it can be used with any type of posterior chamber intraocular lens, in cluding all-polymethylmethacrylate lenses and plate-haptic silicone lenses. Caution should be exercised in performing the procedure on eyes with pseudoexfoliation syndrome, weak zonules from any cause, or zonular dehiscence. After phacoemulsification has been complet ed and the bulk of the lens cortex has been removed, the remaining subincisional cortex is identified (Fig. 1). Viscoelastic material is in jected to reform the anterior chamber and the capsule, and the intraocular lens is implanted into the capsule. The surgeon engages the in traocular lens with a lens or iris manipulator and pulls it into the remaining subincisional cortex. The surgeon spins the lens in the direc tion that the haptics will permit (for example, clockwise for a right-handed lens), holding the lens in the eccentric position while the haptics sweep the cortex out of the capsule (Fig. 2). The procedure is repeated until all of the residual cortex is free. Additional irrigation-aspiration removes the viscoelastic material and the loose cortex from the eye. With silicone intraocular lenses, I advise en gaging the surface of the optic with the lens or iris manipulator, and not the edge of the optic or the optic-haptic junction, as the posterior capsule may tear. The procedure can be per formed even if the anterior capsule has been torn radially, but greater caution must be used.
1. Alpar, J. J.: Cortex at the 12 o'clock position and the role of peripheral iris opening. Ophthalmic Surg. 22:712, 1991. 2. Hagan, J. C. Ill: Irrigation/aspiration handpiece with changeable tips for cortex removal in small incision phacoemulsification. J. Cataract Re fract. Surg. 18:318, 1992. 3. Horiguchi, M.: Instrumentation for superior cortex removal. Arch. Ophthalmol. 109:1170, 1991. 4. Hagan, J. C. Ill: A new cannula for removal of 12 o'clock cortex through a sideport corneal incision. Ophthalmic Surg. 23:62, 1992. 5. Fine, J. H.: Cortical cleaving hydrodissection. J. Cataract Refract. Surg. 18:508, 1992.
Nd:YAG Laser Damage to Silicone Intraocular Lenses Confused With Pigment Deposits on Clinical Examination Gerd U. Auffarth, M.D., T h o m a s J. N e w l a n d , M.D., Thomas A. Wesendahl, M.D., and David J. A p p l e , M.D. Departments of Ophthalmology (G.U.A., T.J.N., T.A.W., DJ.A.) and Pathology (D.J.A.), Storm Eye Institute, Medical University of South Carolina. Sup ported in part by an unrestricted grant from Research to Prevent Blindness, Inc., New York, New York; a Max Kade Postdoctoral Research Grant, Max Kade Foundation, New York, New York (G.U.A.); and a grant from the Deutsche Forschungsgemeinschaft, Bonn, Bad Godesberg, Germany (T.A.W.). Inquiries to David J. Apple, M.D., Department of Oph thalmology, Storm Eye Institute, Medical University of South Carolina, 171 Ashley Ave., Charleston, SC 29425. Neodymium:YAG laser posterior capsulotomy has become the standard treatment for posteri or capsule opacification. 1 It is also used for the opening of membranes or dispersion of pig ment deposits on the anterior surface of an intraocular lens. A variety of iatrogenic complications can re sult from Nd:YAG laser treatment, including corneal endothelial cell loss, increased intraoc ular pressure, uveitis, and retinal detach ment.1"5 Accidental Nd:YAG laser-induced pitting of the surface of intraocular lens optics occurs in up to 30% of cases. 35 At the Center for Intraocular Lens Research, we have analyzed ten explanted silicone intra-
Vol. 118, No. 4
Letters to The Journal
Fig. 1 (Auffarth and associates). A silicone intraoc ular lens with multiple laser burns in the center of the optic. Note the darkness of the deposits (x 25). ocular lenses (nine three-piece, one one-piece). In each patient the ophthalmologists diagnosed pigment and cell deposits on the anterior lens surface. Each patient also had a history of
527
multiple Nd:YAG laser treatments either for posterior capsulectomy or dispersion of pig ment on the anterior surface, or both. Examination with light microscopy and scan ning electron microscopy disclosed that on five of these intraocular lenses the only abnormali ties that could be detected were Nd:YAG laser burns (Figs. 1 and 2). We found 176 laser burns (17.6 ± 12.2 per lens) on the posterior as well as on the anterior optic surfaces of all ten intraocular lenses. The average depth of damage was 143 ± 113.4 μπι. Approximately 61.1 % of the laser burns were in the range of 51 to 175 μιη; 9.3% were deeper than 300 μπι (maximum, 660 μπι = 0.66 mm). The laser burns were a dark color (Fig. 1). These lesions were misinterpreted by some ophthalmologists as pigment deposits. The pa tients then underwent additional Nd:YAG laser treatment, which increased the severity of the laser damage. One patient was treated with the Nd:YAG laser seven times, resulting in 51 burns on the intraocular lens surface. Neodymium:YAG laser-induced damage has
Fig. 2 (Auffarth and associates). Scanning electron micrographs of burns on the surface (x 1,500).
528
AMERICAN JOURNAL OF OPHTHALMOLOGY
been a complication since its application for posterior capsulotomy. Bath, Boerner, and Dang4 reported a case in which an intraocular lens was explanted solely because of Nd:YAG laser damage. Ophthalmologists should be aware that Nd:YAG laser burns on silicone intraocular lenses can sometimes resemble pigment depos its as seen by slit-lamp examination. Careful observation is recommended when examining patients with intraocular lenses before further laser therapy is planned.
References 1. Apple, D. J., Solomon, K. D., Tetz, M. R., Assia, E. I., Holland, E. Y., Legier, U. F. C, Tsai, J. C , Castaneda, V. E., Hoggatt, J. P., and Kostick, A. M. P.: Posterior capsule opacification. Surv. Ophthalmol. 37:73, 1992. 2. Apple, D. J., Kincaid, M. C, Mamalis, N., and Olson, R. J.: Intraocular Lenses. Evolution, Designs, Complications and Pathology. Baltimore, Williams & Wilkins, 1989. 3. Steinert, R. F., Puliafito, C. A., Kumar, S. R., Dudak, S. D., and Patel, S.: Cystoid macular edema, retinal detachment, and glaucoma after Nd:YAG la ser posterior capsulotomy. Am. J. Ophthalmol. 112:373, 1991. 4. Bath, P. E., Boerner, C. F., and Dang, Y.: Pathol ogy and physics of YAG-laser intraocular lens dam age. J. Cataract Refract. Surg. 13:47, 1987. 5. Bath, P. E., Romberger, A. B., and Brown, P.: A comparison of Nd:YAG laser damage thresholds for PMMA and silicone intraocular lenses. Invest. Oph thalmol. Vis. Sei. 27:795, 1986.
Polymerase Chain Reaction Identification of Human Immunodeficiency Virus-1 in Preserved Human Sciera Stuart R. Seiff, M.D., John S. Chang, Jr., M.D., Mark H. Hurt, B.S., and Hassan Khayam-Bashi, P h . D . Departments of Ophthalmology (S.R.S., J.S.C.) and Laboratory Medicine (M.H.H., H.K.B.), University of California, San Francisco, and San Francisco General Hospital. Supported by a grant from the Northern California Society to Prevent Blindness, San Francis co, California. Polymerase chain reaction testing was supported in part by National Institute of Allergy and Infectious Diseases grant P30-AI27763.
October, 1994
Inquiries to Stuart R. Seiff, M.D., Department of Oph thalmology K-301, University of California, San Fran cisco, San Francisco, CA 94143-0730. Preserved human sciera has been used for various surgical procedures on the ocular globe and eyelids. The sciera is typically preserved for transplantation with either 70% isopropyl alcohol or, occasionally, by irradiation. The possibility of transmitting the human immuno deficiency virus (HIV-1) is a major concern in human transplantation, as up to 7% of poten tial organ donors may be seropositive for HIV.1 Serologie HIV testing of donors does not guar antee against infection; it is well known that a potential donor may not test HIV-positive for as long as six months after infection. 2 Human immunodeficiency virus infection has been shown to occur after renal, bone marrow, heart, and skin transplants, and blood transfusions. The virus has been demonstrated in multiple ocular tissues, including the cornea, iris, con junctiva, and retina. 3 However, sciera has not been shown to contain HIV-1. This study was an attempt to show the presence of HIV-1 in sclerae and to determine if identifiable viral genome persists after common methods of pre servation are employed, specifically storage in 70% isopropyl alcohol, heating, freezing, for malin, and irradiation. Polymerase chain reac tion testing was used, realizing that a positive result would indicate the presence of HIV-1 DNA sequences, but not necessarily correlate with infectivity. Four eyes were used in the study. One eye was obtained from the local eye bank and the donor had tested HIV-negative. Three eyes were obtained, after informed consent, from patients who were HIV-positive and had suc cumbed to the complications of the acquired immunodeficiency syndrome (AIDS). Seven 1 x 2-cm pieces of sciera were carefully prepared to avoid contamination with blood. One speci men was from the HIV-negative eye and re ceived no treatment. This served as the nega tive control. Two pieces from different HIV-positive fresh eyes were also studied with out any pretreatment. A specimen from an HIVpositive sciera was heated to 60 C in unpreserved saline for 30 minutes and another was placed in 70% isopropyl alcohol for two weeks. The sixth and seventh specimens were from HIV-positive eyes and were gamma irradiated with 4 million centigray of cesium and pre served with formalin, respectively. All speci mens were frozen to —70 C. A crude lysate was prepared for each individ-
October, 1994
AMERICAN JOURNAL OF OPHTHALMOLOGY
References
Fig. 2 (Miller). The remaining subincisional cortex is loosened after intraocular lens insertion by pulling the lens into the cortex with an iris manipulator and spinning the lens several times.
exclusively for several years. The procedure works best if a three-piece silicone intraocular lens is implanted, but it can be used with any type of posterior chamber intraocular lens, in cluding all-polymethylmethacrylate lenses and plate-haptic silicone lenses. Caution should be exercised in performing the procedure on eyes with pseudoexfoliation syndrome, weak zonules from any cause, or zonular dehiscence. After phacoemulsification has been complet ed and the bulk of the lens cortex has been removed, the remaining subincisional cortex is identified (Fig. 1). Viscoelastic material is in jected to reform the anterior chamber and the capsule, and the intraocular lens is implanted into the capsule. The surgeon engages the in traocular lens with a lens or iris manipulator and pulls it into the remaining subincisional cortex. The surgeon spins the lens in the direc tion that the haptics will permit (for example, clockwise for a right-handed lens), holding the lens in the eccentric position while the haptics sweep the cortex out of the capsule (Fig. 2). The procedure is repeated until all of the residual cortex is free. Additional irrigation-aspiration removes the viscoelastic material and the loose cortex from the eye. With silicone intraocular lenses, I advise en gaging the surface of the optic with the lens or iris manipulator, and not the edge of the optic or the optic-haptic junction, as the posterior capsule may tear. The procedure can be per formed even if the anterior capsule has been torn radially, but greater caution must be used.
1. Alpar, J. J.: Cortex at the 12 o'clock position and the role of peripheral iris opening. Ophthalmic Surg. 22:712, 1991. 2. Hagan, J. C. Ill: Irrigation/aspiration handpiece with changeable tips for cortex removal in small incision phacoemulsification. J. Cataract Re fract. Surg. 18:318, 1992. 3. Horiguchi, M.: Instrumentation for superior cortex removal. Arch. Ophthalmol. 109:1170, 1991. 4. Hagan, J. C. Ill: A new cannula for removal of 12 o'clock cortex through a sideport corneal incision. Ophthalmic Surg. 23:62, 1992. 5. Fine, J. H.: Cortical cleaving hydrodissection. J. Cataract Refract. Surg. 18:508, 1992.
Nd:YAG Laser Damage to Silicone Intraocular Lenses Confused With Pigment Deposits on Clinical Examination Gerd U. Auffarth, M.D., T h o m a s J. N e w l a n d , M.D., Thomas A. Wesendahl, M.D., and David J. A p p l e , M.D. Departments of Ophthalmology (G.U.A., T.J.N., T.A.W., DJ.A.) and Pathology (D.J.A.), Storm Eye Institute, Medical University of South Carolina. Sup ported in part by an unrestricted grant from Research to Prevent Blindness, Inc., New York, New York; a Max Kade Postdoctoral Research Grant, Max Kade Foundation, New York, New York (G.U.A.); and a grant from the Deutsche Forschungsgemeinschaft, Bonn, Bad Godesberg, Germany (T.A.W.). Inquiries to David J. Apple, M.D., Department of Oph thalmology, Storm Eye Institute, Medical University of South Carolina, 171 Ashley Ave., Charleston, SC 29425. Neodymium:YAG laser posterior capsulotomy has become the standard treatment for posteri or capsule opacification. 1 It is also used for the opening of membranes or dispersion of pig ment deposits on the anterior surface of an intraocular lens. A variety of iatrogenic complications can re sult from Nd:YAG laser treatment, including corneal endothelial cell loss, increased intraoc ular pressure, uveitis, and retinal detach ment.1"5 Accidental Nd:YAG laser-induced pitting of the surface of intraocular lens optics occurs in up to 30% of cases. 35 At the Center for Intraocular Lens Research, we have analyzed ten explanted silicone intra-
Vol. 118, No. 4
Letters to The Journal
Fig. 1 (Auffarth and associates). A silicone intraoc ular lens with multiple laser burns in the center of the optic. Note the darkness of the deposits (x 25). ocular lenses (nine three-piece, one one-piece). In each patient the ophthalmologists diagnosed pigment and cell deposits on the anterior lens surface. Each patient also had a history of
527
multiple Nd:YAG laser treatments either for posterior capsulectomy or dispersion of pig ment on the anterior surface, or both. Examination with light microscopy and scan ning electron microscopy disclosed that on five of these intraocular lenses the only abnormali ties that could be detected were Nd:YAG laser burns (Figs. 1 and 2). We found 176 laser burns (17.6 ± 12.2 per lens) on the posterior as well as on the anterior optic surfaces of all ten intraocular lenses. The average depth of damage was 143 ± 113.4 μπι. Approximately 61.1 % of the laser burns were in the range of 51 to 175 μιη; 9.3% were deeper than 300 μπι (maximum, 660 μπι = 0.66 mm). The laser burns were a dark color (Fig. 1). These lesions were misinterpreted by some ophthalmologists as pigment deposits. The pa tients then underwent additional Nd:YAG laser treatment, which increased the severity of the laser damage. One patient was treated with the Nd:YAG laser seven times, resulting in 51 burns on the intraocular lens surface. Neodymium:YAG laser-induced damage has
Fig. 2 (Auffarth and associates). Scanning electron micrographs of burns on the surface (x 1,500).
528
AMERICAN JOURNAL OF OPHTHALMOLOGY
been a complication since its application for posterior capsulotomy. Bath, Boerner, and Dang4 reported a case in which an intraocular lens was explanted solely because of Nd:YAG laser damage. Ophthalmologists should be aware that Nd:YAG laser burns on silicone intraocular lenses can sometimes resemble pigment depos its as seen by slit-lamp examination. Careful observation is recommended when examining patients with intraocular lenses before further laser therapy is planned.
References 1. Apple, D. J., Solomon, K. D., Tetz, M. R., Assia, E. I., Holland, E. Y., Legier, U. F. C, Tsai, J. C , Castaneda, V. E., Hoggatt, J. P., and Kostick, A. M. P.: Posterior capsule opacification. Surv. Ophthalmol. 37:73, 1992. 2. Apple, D. J., Kincaid, M. C, Mamalis, N., and Olson, R. J.: Intraocular Lenses. Evolution, Designs, Complications and Pathology. Baltimore, Williams & Wilkins, 1989. 3. Steinert, R. F., Puliafito, C. A., Kumar, S. R., Dudak, S. D., and Patel, S.: Cystoid macular edema, retinal detachment, and glaucoma after Nd:YAG la ser posterior capsulotomy. Am. J. Ophthalmol. 112:373, 1991. 4. Bath, P. E., Boerner, C. F., and Dang, Y.: Pathol ogy and physics of YAG-laser intraocular lens dam age. J. Cataract Refract. Surg. 13:47, 1987. 5. Bath, P. E., Romberger, A. B., and Brown, P.: A comparison of Nd:YAG laser damage thresholds for PMMA and silicone intraocular lenses. Invest. Oph thalmol. Vis. Sei. 27:795, 1986.
Polymerase Chain Reaction Identification of Human Immunodeficiency Virus-1 in Preserved Human Sciera Stuart R. Seiff, M.D., John S. Chang, Jr., M.D., Mark H. Hurt, B.S., and Hassan Khayam-Bashi, P h . D . Departments of Ophthalmology (S.R.S., J.S.C.) and Laboratory Medicine (M.H.H., H.K.B.), University of California, San Francisco, and San Francisco General Hospital. Supported by a grant from the Northern California Society to Prevent Blindness, San Francis co, California. Polymerase chain reaction testing was supported in part by National Institute of Allergy and Infectious Diseases grant P30-AI27763.
October, 1994
Inquiries to Stuart R. Seiff, M.D., Department of Oph thalmology K-301, University of California, San Fran cisco, San Francisco, CA 94143-0730. Preserved human sciera has been used for various surgical procedures on the ocular globe and eyelids. The sciera is typically preserved for transplantation with either 70% isopropyl alcohol or, occasionally, by irradiation. The possibility of transmitting the human immuno deficiency virus (HIV-1) is a major concern in human transplantation, as up to 7% of poten tial organ donors may be seropositive for HIV.1 Serologie HIV testing of donors does not guar antee against infection; it is well known that a potential donor may not test HIV-positive for as long as six months after infection. 2 Human immunodeficiency virus infection has been shown to occur after renal, bone marrow, heart, and skin transplants, and blood transfusions. The virus has been demonstrated in multiple ocular tissues, including the cornea, iris, con junctiva, and retina. 3 However, sciera has not been shown to contain HIV-1. This study was an attempt to show the presence of HIV-1 in sclerae and to determine if identifiable viral genome persists after common methods of pre servation are employed, specifically storage in 70% isopropyl alcohol, heating, freezing, for malin, and irradiation. Polymerase chain reac tion testing was used, realizing that a positive result would indicate the presence of HIV-1 DNA sequences, but not necessarily correlate with infectivity. Four eyes were used in the study. One eye was obtained from the local eye bank and the donor had tested HIV-negative. Three eyes were obtained, after informed consent, from patients who were HIV-positive and had suc cumbed to the complications of the acquired immunodeficiency syndrome (AIDS). Seven 1 x 2-cm pieces of sciera were carefully prepared to avoid contamination with blood. One speci men was from the HIV-negative eye and re ceived no treatment. This served as the nega tive control. Two pieces from different HIV-positive fresh eyes were also studied with out any pretreatment. A specimen from an HIVpositive sciera was heated to 60 C in unpreserved saline for 30 minutes and another was placed in 70% isopropyl alcohol for two weeks. The sixth and seventh specimens were from HIV-positive eyes and were gamma irradiated with 4 million centigray of cesium and pre served with formalin, respectively. All speci mens were frozen to —70 C. A crude lysate was prepared for each individ-