were designed to be safety studies, some improvement of visual function was also reported. However, further studies are needed to establish long-term efficacy and safety.

X-LINKED JUVENILE RETINOSCHISIS

X-linked juvenile retinoschisis is one of the juvenile-onset macular dystrophies that is characterized by decreased central vision, cystic changes in the macula, peripheral retinal schisis in 50% of patients, and selective reduction of ERG b-wave amplitude. The foveal cystic changes are usually apparent very early after birth, due to splitting within inner retinal layers. However, visual acuity is not severely reduced until the fifth or sixth decade of life. Other clinical features include vitreous veils, vitreous hemorrhage, pigmentary retinopathy, and dendritiform lesions of the retina. The gene XLRS1 encodes for the protein retino­ schisin that is responsible for cell-to-cell adhesion; mutation in this gene causes splitting of the retina and development of cystic spaces in the inner nuclear and outer plexiform layers of the retina.

Treatment

Although there is no treatment available for the disease itself, a recent study reported improvement in visual acuity and retinal thickness on OCT in a substantial number of patients (n = 8) treated with topical dorzolamide.39 Similar to patients with RP and CME, the recommendation is that these patients on topical dorzolamide should be monitored with an OCT at regular intervals.

SUMMARY AND KEY POINTS

In summary, this is an era when clinicians, basic scientists, molecular biologists, pharmaceutical companies, and funding agencies have all teamed up to identify more genes, provide phenotype–genotype correlations, and prepare animal models of various diseases in an attempt to understand better the pathogenesis of some of these yet untreatable conditions. There are several ongoing treatment trials in various phases which provide a reason for optimism in the future.

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Pharmacotherapy to Amenable Diseases Retinal • 3 section