Abstract
Purpose: :
To determine whether visual function and nystagmus eye movements are improved with tinted CL correction compared with spectacle and un-tinted CL correction in patients with Albinism. Preliminary results on 3 subjects were reported last year. Complete results on 20 subjects are now being reported.
Methods: :
20 subjects were fitted with soft toric CL’s that were then custom tinted to create an artificial iris. Four dependent variables were measured with three forms of vision correction (spectacle correction, un-tinted CL and tinted CL) including visual acuity (VA), contrast sensitivity (CS) with and without glare, and nystagmus eye movement recordings. Patients’ subjective evaluation of their visual comfort and clarity, and their perception of change in glare and light sensitivity were also evaluated by means of a short questionnaire. The EDTRS chart was used to measure visual acuity. The CSV-1000HGT (halogen glare test) and 1000E (Contrast Sensitivity chart) were used to measure the contrast sensitivity function and effect of glare. Nystagmus eye movement characteristics of amplitude, frequency, intensity and foveation were recorded and analyzed with an ISCAN system (RK 826PCI) that uses a video based dark pupil-to-cornea reflection method.
Results: :
Mean VA was significantly improved with tinted CL correction (F = 28.148, p < 0.05). Mean CS under normal testing conditions was also significantly improved (F=16.944, p < 0.05) as was CS with glare (F = 6.667, P < 0.05). ISCAN recordings with 3 runs in each of 5 gaze positions showed reduced nystagmus intensity with tinted contact lenses (x2 = 30.7, p < 0.05). Patients subjectively reported reduced sensitivity to light and decreased glare with tinted contact lenses.
Conclusions: :
The results indicate that VA, Nystagmus intensity and CS with and without glare were significantly improved with tinted CL wear in patients with albinism.
Keywords: low vision • nystagmus • contact lens