Bilateral Paralimbal Scleromalacia Perforans

Bilateral Paralimbal Scleromalacia Perforans

Vol. 109, No.2 Letters to the Joumal tients with acquired immunodeficiency syndrome. Gastrointest. Radiol. 13:358, 1988. 5. Winward, K. E., and Curt...

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Vol. 109, No.2

Letters to the Joumal

tients with acquired immunodeficiency syndrome. Gastrointest. Radiol. 13:358, 1988. 5. Winward, K. E., and Curtin, V. T.: Conjunctival squamous cell carcinoma in a patient with human immunodeficiency virus infection. Am. J. Ophthalmol. 107:554, 1989.

Bilateral Perforans

Paralimbal

Scleromalacia

Thomas H. Mader, M.D., R. Doyle Stulting, M.D., and Hal H. Crosswell, Jr., M.D. The Emory Eye Center, Emory University School of Medicine (T.H.M., R.D.S.), and Department of 0rhthalmology, University of South Carolina Schoo of Medicine (H.H.C.). Inquiries to Thomas H. Mader, M.D., Cornea Service, Emory Eye Center, 1327 Clifton Rd. N.E., Atlanta, GA 30322.

Paralimbal scleromalacia perforans is a rare condition characterized by a slowly progressive, noninflammatory, painless scleral thinning at the corneosclerallimbus, which leads to iris prolapse. 1 It occurs in young adults in the absence of systemic disease or previous ocular mflammation.P This condition is in sharp contrast to most cases of scleral thinning that are usually seen in association with local ocular inflammation or concurrent chronic systemic inflammatory disease. Paralimbal scleromalacia perforans is reported to have a good prognosis without treatment.! In October 1983 a 33-year-old woman had a one-year history of foreign body sensation and a ten-day history of decreased vision in the right eye. The patient had no history of ocular pain, inflammation, or previous ocular problems. Medical history and family history did not indicate rheumatoid disease or any other significant systemic disease. Visual acuity was R.E.: 20/40 and L.E.: 20/20. Both pupils reacted normally to light, but the right pupil was slightly displaced superonasally. Intraocular pressures by applanation tonometry were R.E.: 1 mm Hg and L.E.: 9 mm Hg. The patient had bilateral paralimbal scleral thinning from the 10 o'clock to the 3 o'clock meridian in the right eye and from the 8 o'clock to 2 o'clock meridian in the left eye with almost complete absence of the sclera on the right eye. The iris could be

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seen through the conjunctiva and sclera. There were no signs of inflammation. A diffuse subconjunctival bleb was superior to the thin sclera. The anterior chambers were clear and of normal depth. Using gonioscopy, a slit opening was visible in the right eye along the trabecular meshwork from the 12 o'clock to 2 o'clock meridian. The corneas and lenses were clear. Mild disk edema was present in the right eye. Results of laboratory studies including complete blood cell count, platelet count, VDRL test, erythrocyte sedimentation rate, urinalysis, electrolyte count, antinuclear antibody level, vitamin A level, rheumatoid factor, and serum protein electrophoresis were normal. No ocular therapy was instituted after initial examination. Spectacles were recommended during the day and a shield at night to protect against inadvertent trauma. An examination in January 1984 disclosed further thinning of the sclera superiorly in the right eye. Over the next three months, the sclera continued to thin at the corneosclerallimbus bilaterally, more progressive in the right eye. In March 1984, with intraocular pressure of 0 mm Hg in the right eye and decreasing visual acuity, visual fields confirmed enlargement of the blind spot. A lamellar sclerokeratoplasty was performed to reinforce the area of extreme scleral thinning. Two months after the operation, a subconjunctival filtering bleb was noted at the superior border of the lamellar graft. By six months postoperatively, the patient's visual acuity was correctable to 20/25 in the right eye. The vision remained stable for the next three years. In early 1988 the patient returned with a corrected

Fig. 1 (Mader, Stulting, and Crosswell). Scleromalacia with peaked pupil in the left eye.

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February, 1990

AMERICAN JOURNAL OF OPHTHALMOLOGY

References 1. Francois. J.: Scleromalacia perforans, arthritis deformans and pemphigus. Trans. Ophthalmol. Soc. U.K. 71:61, 1951.

Fig. 2 (Mader, Stulting, and Crosswell). Gonioscopy of the left eye showing iris incarceration into linear scleral perforation. visual acuity of 20/20 in both eyes. The intraocular pressure was R.E.: 6 mm Hg and L.E.: 8 mm Hg. The left pupil was peaked toward the 10 o'clock meridian. Gonioscopy showed iris incarceration into a linear scleral perforation along the trabecular meshwork from the 10 o'clock to 12 o'clock meridian (Figs. 1 and 2). Repeated physical examinations over a fiveyear period disclosed no systemic illness. This is a case of bilateral indolent loss of tissue at the corneoscleral junction in an otherwise healthy woman. This condition, known as paralimbal scleromalacia perforans or spontaneous scleral intercalary perforation, was first described as a clinical entity by Franceschetti and Bischler in 1950. 3 Using the strict criterion of painless, noninflammatory, spontaneous paralimbal thinning in the absence of systemic disease or ocular inflammation, two cases have been reported." This condition appears to be a degenerative process that occurs at the corneoscleral junction in the area of the trabecular meshwork. One report suggests that a small vessel may run through the defect to anastomose with the posterior ciliary circulation. This may be the site of spontaneous perforation." We saw no evidence of anastomosing vessels in our patient. We believe the disease involves a progressive scleral thinning at the trabecular meshwork. Thinning may progress to a linear perforation with incarceration of uveal tissue. This condition is described as entirely benign, nonprogressive, and requiring no treatment.' However, our case demonstrates that paralimbal scleromalacia perforans can cause visual loss from chronic hypotony.

2. Duke-Elder, S., and Leigh, A. G.: Diseases of the Outer Eye. Cornea and Sclera. In Duke-Elder, S. (ed.): System of Ophthalmology, vol. 8, pt. 2. St. Louis, C. V. Mosby, 1965, pp. 1054-1055. 3. Franceschetti, A., and Bischler, V.: La sclerite nodulaire nicrosante et ses rapports avec la scleromalacia. Ann. Ocul. 183:737, 1950. 4. Sorensen, T. B.: Paralimbal scleromalacia. Acta Ophthalmol. 53:901. 1975. 5. Watson, P.: Diseases of the sclera and episclera. In Duane, T. D. (ed.): Clinical Ophthalmology, vol. 4. Hagerstown, Harper & Row, 1979, p. 36.

Horizontal Homonymous Sectoral Field Defect After Ischemic Infarction of the Occipital Cortex Murray Grossman, M.D., Steven L. Galetta, M.D., Charles W. Nichols, M.D., and Robert I. Grossman, M.D. Department of Neurology (M.G., S.L.G.) and Radiology (R.LG.), Hospital of the University of Pennsylvania, and Department of Ophthalmology, Scheie Eye Institute (S.L.G., C.W.N.). Inquiries to Murray Grossman, M.D., Department of Neurology, Hospital of the University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104. In cases of horizontal sectoral visual field defects, lesions have been restricted to the lateral geniculate nucleus of the thalamus-! or the optic radiations.v' We treated a patient with a horizontal homonymous sectoral field defect after an ischemic infarct to the occipital cortex in the region of the calcarine fissure. A 77-year-old right-handed man was noted during routine examination to have a homonymous defect in the left visual field. The patient was observed in the clinic for borderline increased intraocular pressure that had been stable for 2* years. A slight optic cup asymmetry was present (right eye, 0.3; left eye, 0.2). Results of computerized perimetry were normal several months before this occurrence. Medical history was significant for systemic hyperten-