Perimetric testing of tritan deficiency.

Three members of a family with dominantly inherited juvenile optic atrophy tested with a computerized perimeter employing violet and blue-green test lights and low-intensity white background, all showed larger reduction in the relative sensitivity to violet light in the more central parts of the visual field compared with the periphery within 30 degrees from the center. Two subjects had typical optic atrophy, centrocecal scotoma and lower than normal visual acuity. In 1 subject with good visual acuity of both eyes, no optic atrophy was observed but there was impairment in the luminosity function (tested with white test object on white background) of the peripheral visual field.