[Visual rehabilitation in patients with hereditary retinal dystrophy: current data from a Low Vision Department]

Especially during adolescence, hereditary retinal dystrophies can cause visual impairment. Because of their high mobility and working activities, these patients represent a great challenge for a Low-Vision Department. This study illustrates the spectrum of appropriate magnifying devices for them, as prescribed in our Low-Vision Department.

Between January 2003 and October 2004, we took care of 2,500 patients in our Low-Vision Department. 141 (5.6 %) of them suffered from a hereditary retinal dystrophy. After ascertaining the best corrected distance and near visual acuity as well as the magnification demand we prescribed the appropriate optic or electronic magnifying aids.

The preferential age for the first visit was between 15 and 40 years. Within the retinal dystrophies we saw cone-rod dystrophy in 46 (33 %) patients, Stargardt's disease in 38 (27 %), retinitis pigmentosa in 37 (26 %), albinism in 15 (11 %) and achromatopsia in 5 (3 %) patients. The average of the best corrected distance visual acuities of the better eye was 0.142 (SD +/- 3.3 lines), the best corrected visual acuity for reading was 0.124 (SD +/- 6.1 lines). The average magnification demand was 5 x (SD +/- 6.7). The most prescribed optic magnifying aids were distance spectacles and magnifying glasses (each 20 %), monocular telescopes, contrast enhancing filters (each 13 %) and reading glasses (8 %). Electronic magnifying aids were prescribed in only 8 %.

Fluent reading ability in hereditary retinal dystrophies could be achieved mostly by optic magnifying aids. The high proportion of prescribed distance glasses and magnifying glasses shows that often simple magnifying aids are suitable for these patients. Because of the high photophobia, contrast-enhancing filters should always be considered.