Functional and clinical findings in 3 female siblings with crystalline retinopathy

Purpose To present functional and clinical findings in three female siblings with crystalline retinopathy. Methods Functional and clinical examinations, including full-field and multi-focal electroretinograms (ERG), visual field, dark adaptation and fundus fluorescein angiography (FFA) were performed in three female siblings of a nonconsanguineous Chinese family, who exhibited characteristic retinal crystalline flecks of Bietti crystalline retinopathy. Results Ophthalmological examination revealed similar findings in the first and second daughter of the family. Best-corrected visual acuity was hand movement and finger counting respectively and funduscopic examination showed RPE clumping and relatively fewer yellow-white deposits in the posterior pole and mid-peripheral retina. FFA revealed massive RPE and choriocapillaris destruction. Ganzfeld ERG was undetectable or reduced markedly and multifocal ERG showed all responses were markedly depressed. Ophthalmological examination showed relative preservation of retinal function in the third daughter of the family (the proband). Best-corrected visual acuity was 0.5 in the right eye and 0.4 in the left eye. Funduscopic examination showed numerous crystal deposits scattered throughout the posterior pole. Dark adaptation revealed rod thresholds elevated dramatically and visual field examination demonstrated paracentral scotomas in both eyes. Full-field ERG was decreased slightly and multifocal ERG showed the central responses were markedly depressed. Conclusion The present study describes typical crystalline retinopathy affecting three female siblings in a family.