PURPOSE: To investigate severe unilateral vision loss in a choroideremia carrier. DESIGN: Case report. METHODS: Ocular examination, genetic testing, Humphrey visual fields, full-field and multifocal (mf) electroretinogram (ERG) tests were used to study a family with choroideremia. RESULTS: In a carrier with unilateral central vision loss, mfERG showed severely reduced amplitudes which correlated with a band of retinal pigment epithelial and choroidal atrophy in the macula, a dense central scotoma on Humphrey visual fields testing, and decreased ERG amplitudes. CONCLUSIONS: Multifocal ERG may be a sensitive tool to measure functional abnormalities in choroideremia carriers. Mosaic inactivation of the normal gene may cause expression of the mutation with severe vision loss in choroideremia carriers.
PURPOSE: To investigate severe unilateral vision loss in a choroideremia carrier. DESIGN: Case report. METHODS: Ocular examination, genetic testing, Humphrey visual fields, full-field and multifocal (mf) electroretinogram (ERG) tests were used to study a family with choroideremia. RESULTS: In a carrier with unilateral central vision loss, mfERG showed severely reduced amplitudes which correlated with a band of retinal pigment epithelial and choroidal atrophy in the macula, a dense central scotoma on Humphrey visual fields testing, and decreased ERG amplitudes. CONCLUSIONS: Multifocal ERG may be a sensitive tool to measure functional abnormalities in choroideremia carriers. Mosaic inactivation of the normal gene may cause expression of the mutation with severe vision loss in choroideremia carriers.
Authors: Vera L Bonilha; Karmen M Trzupek; Yong Li; Peter J Francis; Joe G Hollyfield; Mary E Rayborn; Nizar Smaoui; Richard G Weleber Journal: Ophthalmic Genet Date: 2008-09 Impact factor: 1.803