Interocular difference and duration for doubling of the minimal angle of visual resolution in patients with Stargardt disease.

PURPOSE: To determine the extent of interocular difference in visual acuity (VA) and the time to at least double the minimal angle of resolution (MAR) in a cohort of patients with Stargardt disease. METHODS: One hundred fifty patients with Stargardt disease who were examined at least four times over a minimum period of 3 years were identified and their VA and age at each visit recorded. The maximum interocular difference of VA was determined by whether the MAR between the two eyes differed by less than a factor of 2 or by a factor of 2 or greater. Differences in maximum VA between the two eyes were also examined according to a Bland-Altman-type approach. One hundred thirty-one eyes from 76 patients were subjected to survival analysis to determine whether the time to at least double the MAR was dependent on age at baseline or starting VA. RESULTS: Of the 150 patients, 48% had interocular MAR that differed maximally by a factor of less than 2. Thirty-five percent showed a maximum interocular difference in their Snellen VA of less than one line. The Bland-Altman- type analysis showed that maximum interocular acuity difference was dependent on the mean acuity of the two eyes. The hazard for at least doubling the MAR was related to baseline vision and patient age. CONCLUSIONS: This information has clinical significance for patient counseling and for monitoring possible benefits and patient selection in future treatment trials.

Diagnosis in a patient with fundus albipunctatus and atypical fundus changes.

We report a case of an 11-year old Caucasian female with nyctalopia since early childhood with an atypical clinical presentation of fundus albipunctatus (FA), and a novel mutation in the RDH5 gene. In addition to white spots in the fundus, patchy areas of hypopigmentation were noted, which were reminiscent for an early stage of retinitis punctata albescens (RPA). Electroretinographic testing (ERG) showed a non-detectable, dark adapted, isolated rod response and a markedly decreased combined rod and cone response to an achromatic stimulus. After patching one eye overnight, both the isolated rod response and combined rod and cone scotopic white flash response were normal. A Goldmann-Weekers dark adapted final threshold response was also within the normal range. The patient showed a previously reported heterozygous mutation for Gly238Trp, and a novel Arg157Gln mutation. Genetic testing and extended ERG and psychophysical testing may be necessary to diagnose FA from early stages of progressive RPA.

Dorzolamide use in the management of macular cysts in a patient with enhanced s-cone syndrome.

PURPOSE: To determine the efficacy of dorzolamide ophthalmic solution, a carbonic anhydrase inhibitor, for treating macular schisis in enhanced S-cone syndrome. METHODS: A 12-year-old white boy was diagnosed with enhanced S-cone syndrome based on the patient's history of night blindness, fundus examination, and electroretinogram testing that showed nondetectible rod function and atypical cone function consistent with an overabundance of blue cones. Time domain optical coherence tomography (OCT) baseline scans confirmed the presence of macular cysts, and the patient was started on dorzolamide ophthalmic drops twice a day. A Fourier domain-OCT unit was used to monitor any changes in the macular cysts. RESULTS: After 8 weeks of starting the eye drops, the Fourier domain OCT showed an improvement in the macular cysts of the right eye with notable but more moderate changes in the left. Visual acuity improved one line in the right eye compared with baseline. Ten weeks later, the patient showed a further improvement in macular cysts by OCT testing in both eyes, with visual acuity improvement of one line in the left eye, and sustained one line improvement in the right. CONCLUSION: The treatment of macular cysts using a topical carbonic anhydrase inhibitor twice a day can potentially reduce foveal cystic changes and possibly improve visual acuity in at least some patients with enhanced S-cone syndrome.