A form of congenital stationary night blindness with apparent defect of rod phototransduction.

摘要: We report findings obtained from an individual with unusual form of congenital stationary night blindness (CSNB). Although the rhodopsin density difference this subject was normal, there no evidence rod-mediated visual function. Dark-adapted thresholds were cone-mediated, and darkadapted electroretinograms (ERGs) represented activity cone system exclusively. ERG a- b-waves under light-adapted conditions normal. The absence a rod a-wavc but presence normal density, in combination function, indicates that CSNB likely involves defect phototransduction is limited to rods. In addition, b-wavc responses high luminance flashes larger than dark-adapted responses, whereas amplitudes reduced by light adaptation. These results address proposed mechanisms which adaptation might enhance responses. Invest Ophthalmol Vis Sci 31:237-246, 1990 Patients (CSNB) most frequently have primary characterized functionally reduction b-wave electroretinogram (ERG) elevation absolute threshold. 1 " 10 However, as measured fundus reflectometry, amplitude a-wave often are 410