Snowflake degeneration: an independent entity or a variant of retinitis pigmentosa?

We examined eight members of three generations of a family with a history of hereditary retinal degenerative disease. Four affected members have multiple whitish retinal dots resembling snowflakes. Other positive ocular findings in the four members with retinal flakes include myopia, cataract, fibrillary vitreous degeneration with occasional strands, attenuated retinal arterioles, sheathed retinal vessels, occlusion of small retinal vessels, white with and without pressure, annular macular pigment defects, and occasional spicules of pigment. Goldmann perimetry showed irregular annular scotomas in three patients. Electroretinographic response was extinguished in one and subnormal in three. Electro-oculography showed the light rise-to-dark trough ratio to be decreased in the affected patients. Based on results of vitreoretinal biomicroscopy, Goldmann perimetry, and visual electrodiagnostic testing, we suspect that snowflake degeneration may be just a variant of retinitis pigmentosa.