Correlation of clinicopathologic findings in a patient. Congenital night blindness, branch retinal vein occlusion, cilioretinal artery, drusen of the optic nerve head, and intraretinal pigmented lesion

The ocular clinicopathologic features of this unique patient were congenital stationary night blindness, drusen of the optic nerve head, cilioretinal artery, intraretinal pigmented lesion, and branch retinal vein occlusion. Photocoagulation therapy led to total disappearance of the neovascular tissue, clinically and histopathologically. Histopathologic examination showed an occluded branch vein associated with a sclerotic retinal arteriole. Peripheral to the site of venous occlusion, inner ischemic retinal atrophy was present. The normal complement of rod and cone photoreceptors supports the view that the night blindness in this case was an abnormality in the neural transmission and not on a morphological basis. The pigmented intraretinal lesion proved to be a localized area of retinal and choroidal neovascularization with anastomosis and secondary retinal pigment epithelial hyperplasia. This lesion was identical to Fuchs' dot of myopia but out patient was hyperopic.

Congenital stationary night blindness: an animal model

Electroretinographic studies of myctalopic Appaloosa horses demonstrated photopic and scotopic abnormalities similar to those in humans with congenital stationary night blindness (CSNB) of the Schubert-Bornschein type. The phototopic abnormalities consisted of reduced b-wave amplitudes and slower than normal b-wave implict time. The dark-adapted ERG's consisted of a simple negative potential; the scotopic b-wave was nonrecordable. However, a normal c-wave was present in the dark-adapted response. Histologic studies demonstrated no structural abnormalities that could explain the functional defect.

Paradoxical pupillary responses in congenital stationary night blindness

Three unrelated boys, ages 2, 6, and 10 years, who have congenital stationary night blindness with myopia and a Schubert-Bornschein-type electroretinogram finding, were found to show a "paradoxical" pupillary constriction in darkness. When examining room lights are turned out, the patient's pupils briskly constrict and slowly dilate. Older night blind male relatives of these boys did not show this abnormal constriction to darkness.

Fluorescein angiography and vitamin A and oxalate levels in fundus albipunctatus

Two patients had fundus albipunctatus, one of the variants of congenital stationary night blindness. Neither the white dots in the retinas of these patients nor the retarded course of dark adaptation characteristically associated with the disease could be attributed to vitamin A deficiency or raised oxalate levels since both substances were present in normal amounts. Fluorescin angiography showed multiple discrete lesions in the pigment epithelium not coincident with the ophthalmoscopically visible changes. Since the pigment epithelium is the storage site for bleached visual pigment, these findings suggest abnormalities that underlie the major functional deficit in this disease, that is, the slow recovery of retinal sensitivity.

Congenital stationary nightblindness

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