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The misdiagnosis of retinoschisis

clinical entity, which was first described by Bartels (1933). In the majority of cases, it is asymptomatic, infero-temporal, nonprogressive and does not require treatment unless complicated by an outer layer detachment (Byer 1968, 1986). Confusion of the retinoschisis elevation with rhegmatogenous retinal detachment does occur and results in unnecessary laser or surgical intervention. We present four cases in which the diagnosis was in dispute and define characteristics that made for the diagnosis of retinoschisis. Case #1: A 26-year-old male was referred to the retina service after three retina specialists had diagnosed bilateral retinal detachment and recommended urgent surgery. He was asymptomatic. On examination, his visual acuity was 20 ⁄ 20 with spherical equivalent corrections of )12.00 in both eyes. Funduscopic examination revealed bilateral 360 peripheral retinal elevations anterior to the equator and extending to the ora serrata. In the right eye, there were horseshoe retinal tears at 1:30, 5:30 and 7:00 o’clock near the posterior edge of the retinal elevation (Fig. 1, left). In the left eye, seven horseshoe tears were found near the posterior edge of the elevations at 12:30, 3:30, 4:00, 5:30, 7:00 and 11:00 o’clock (Fig. 1, right). The patient was diagnosed as having retinoschisis with multiple inner layer breaks in both eyes. He was taught how to monitor his peripheral visual field and asked to report any change without delay. Examination 11 and 22 months later revealed no change in the extent of the retinal elevations, and no pigment lines had developed at the posterior border of the retinal elevations. His visual acuity remained 20 ⁄20 in both eyes. A 360 of retinoschisis in the periphery is not exceptional. The presence of retinal breaks provoked some concern, but considering that the shape of the retinal elevations did not relate to the breaks, did not progress and did not cause a pigmentation line to form over 22 months, reassured us that the breaks were in the inner layers of peripheral schisis. Case #2: A 35-year-old female was referred to the retina service in October 1989 for treatment of a retinal detachment in her left eye. Her corrected visual acuity with )9.00 in both eyes was 20 ⁄ 20. The fundus examination revealed bilateral peripheral inferotemporal retinal elevations anterior to the equator. There were multiple holes in the elevation in the left eye (Fig. 2, left). Bilateral retinoschisis was diagnosed, and the patient was advised upon how to monitor her visual field and asked to report any changes without delay. Five years later in June 1994, the patient presented complaining of a shadow developing supero-nasally in the visual field of the left eye. Fundus examination revealed an infero-temporal retinal detachment extending posterior to the schisis elevation and to within a disc diameter of the macula. The detachment emanated from an outer layer break that had developed at the inferior edge of the temporal retinoschisis (Fig. 2, right). A local buckle procedure with a silicone sponge applied to the outer layer break reattached the retina without drainage of the subretinal fluid. The schisis elevation remained unchanged. Case #3: A 46-year-old female first came to the retina clinic in February 1999 looking for a second opinion. She had undergone surgery for ‘retinal detachment’ in the left eye 4 months before and was told that it was not successful. She did not have any visual symptoms and her corrected visual acuity with )7.50 spheres in both eyes was 20 ⁄ 20. Examination of the right eye revealed an inferior bullous retinal elevation extending posteriorly to within two disc diameters of the macula. There was a round hole at 6 o’clock anterior to the equator. A laser test through the hole was positive for retinoschisis (Fig. 3, left). Examination of the left eye revealed an infero-temporal buckle covered with coagulation scars and with retinoschisis on the internal surface that extended beyond the posterior edge of the buckle (Fig. 3, right). No additional surgery was recommended, and the patient was instructed upon how to monitor her visual field. Eight years after the initial presentation, the retinoschisis posterior to the buckle in the left eye was unchanged. The right eye developed Diagnosis ⁄Therapy in Ophthalmology