Multifocal electroretinography in segmental retinitis pigmentosa

Purpose. Generalized retinal degenerations such as retinitis pigmentosa may manifest with focal retinal dysfunctions. These may be detected objectivel y by new electrophysiological techniques, such as multifocal electroretinog raphy (ERG). Case report. A mother and daughter,aged 81 and 46 years, showed bilateral c audal bone spiculae formations with corresponding cranial visual field defe cts in the static perimetry of the central visual field (Octopus) and in th e kinetic perimetry (Goldmann). Results. Pattern VEP, pattern ERG, EOG,and cone ERG were within the normal range. The scotopic ERG was in the lower normal range. The multifocal cone ERG of the central 50 degrees showed reduced amplitudes and prolonged laten cies in the first-order response component. These findings corresponded to the area of the bone spiculae and the scotomata. Conclusion. Multifocal ERG enables the detection of focal retinal cone dysf unction in segmental retinitis pigmentasa. It is an additional tool that ma y aid in the diagnosis and classification of this disease.