Abstract
Abstract: :
Purpose:X-linked cone rod dystrophy is a rare hereditary disorder, with less than five affected families being described. One problem with counseling families with this disorder has been that many carriers are asymptomatic and have normal or minimal non-descriptive changes on examination, including a normal full-field electroretinogram (ERG). We describe the evaluation of an affected family by multifocal ERG, which aided in a more detailed evaluation of carrier status. Methods:We examined members of a family with X-linked cone rod dystrophy whose pedigree of affected members span five traceable generations. We were able to examine affected and unaffected males as well as unaffected and carrier females from three generations. All probands had careful evaluation of their symptoms, undergoing full clinical examination, color testing, photography and full-field as well as multifocal ERG testing. Results:Five symptomatic males had decreased visual acuity, various degrees of myopia, and significant abnormalities on both full-field and multifocal ERG. Funduscopic examination of older affected males revealed a golden tapetoretinal sheen and a 10-15 year history of reduced visual acuity (20/200-20/400). Color testing was abnormal on all affected males. The presumed carrier females had completely normal to mildly subnormal clinical exams with normal acuities, color vision, and normal to mildly deviant non-pathognomonic full-field ERG changes. Multifocal ERG examination carriers were atypical with a pattern of patchy parafoveal depression. Conclusion:X-linked cone rod dystrophy is a rare disease. We demonstrate with this newly described family, the ability to characterize identify female carriers with the use of multifocal ERG.
Keywords: 395 electroretinography: clinical • 562 retinal degenerations: hereditary • 554 retina