Transsynaptic degeneration of the retinogeniculate pathways is well documented to occur in nonhuman primates when the cerebral lesion occurs even during adulthood. In case of humans, retrograde transsynaptic degeneration of the retinogeniculate pathways has been shown to occur following prenatal or perinatal lesions, but its occurrence after cerebral lesions in adults is considerable rare. It is, however, well established that retrograde transsynaptic degeneration affects other neural systems in humans even when the injury occurs during adulthood. Some histopathological evidence points to the possibility of transsynaptic degeneration of the retinogeniculate pathway in humans even when the lesion occurs in adults, but the clinical significance is unknown.'