Abstract
Purpose: :
To evaluate the visual sensitivity of areas with and without flecks in patients with Stargardt disease and compare the results obtained in these areas.
Methods: :
Twenty-three patients (9 from Columbia University in New York and 14 from the Eye Clinic in Florence) with Stargardt disease (ABCA4 related maculopathy) aged 41 +/- 15.72 (range 22-68 yrs.) with visual acuities >=20/200 were studied. Subjects with refractive errors (+/- 5D), cataract, other ocular diseases, pupil diameter after dilation <4 mm, age > 70 years, and previous photorefractive treatment were excluded from the study. The following tests were performed: fundus photography, fundus-controlled perimetry with the Nidek MP-1 (10-2 program, 4-2 procedure), and fundus autofluorescence imaging (Heidelberg Retinal Angiograph 2). The MP-1 results were superimposed on the fundus autofluorescence image. For each patient the eye that had the most flecks associated with MP-1 test locations was selected for analysis. Visual sensitivity in areas with or without flecks at the same distance from the fovea was evaluated. The sensitivity (in dB) for each flecked area was compared with the value for the nearest non-flecked area. Mean sensitivity values for flecked versus non-flecked areas were compared.
Results: :
For 23 eyes of 23 patients, the preferred retinal location was foveal in 4 eyes and extrafoveal in 19 (superior in 16 eyes; inferior in 1, temporal in 1 and nasal in 1). A total of 1564 locations (68 locations for the 10-2 program) were tested with the MP-1. The test light was associated with 82 flecked areas; the mean retinal sensitivity was 13.51 +/- 3.46 dB. In the 82 neighbouring non-flecked areas the mean sensitivity was 15.00 +/- 3.29 dB. The difference was statistically significant (p< 0.001).
Conclusions: :
In Stargadt disease flecks are associated with decreased visual sensitivity.
Keywords: retinal degenerations: hereditary • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical