Prospective Open Label Randomized Controlled Clinical Study Evaluating the Efficacy of Perceptual Learning in Improving Vision among Patients with Congenital Nystagmus

Idan Hecht MD^1,2, Sigal Zmujack-Yehiam MD^1,2, Ora Abaev¹, Adi Einan-Lifshitz MD^1,2, Eran Pras MD^1,2

1. Department of Ophthalmology, Shamir Medical Center, Zerifin, Israel.
2. Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.

Idan Hecht MD^1,2, Sigal Zmujack-Yehiam MD^1,2, Ora Abaev¹, Adi Einan-Lifshitz MD^1,2, Eran Pras MD^1,2

1. Department of Ophthalmology, Shamir Medical Center, Zerifin, Israel.
2. Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.

Background: There are limited treatment options to improve vision in patients with congenital nystagmus. We examined the use of repeated visual stimulation with Gabor Patches to achieve that goal.

Methods: In a prospective randomized (3:1) controlled open label study, patients aged 9-55 years with congenital nystagmus and best corrected visual acuity (BCVA) between 20/40–20/200 were included. The treatment group underwent visual stimulation for four months, controls were treated with sham stimuli. BCVA, contrast sensitivity, and stereoacuity were assessed.

Results: 26 patients were treated and 10 served as control. Mean age was 22.47±12 years. 6/26 (23%) of treatment subjects achieved driving license BCVA (20/40) vs 1/10 (10%) of controls. Distance treated BCVA improved by 0.10±0.07 logMAR (one ETDRS line) compared with 0.015±0.09 logMAR in controls (p=0.006). Near BCVA improved by 0.16±0.14 logMAR (1.6 ETDRS lines) compared with 0.05±0.13 logMAR in controls (p=0.040). 88% (8/9) of study patients who had no binocularity prior to treatment achieved binocularity (mean 630’) as opposed to 25% (1/4) of controls (p=0.10). Mean stereoacuity and contrast sensitivity improved by 801±730’ and 292±391% in the study group as opposed to 246±376’ and 152±67% in controls respectively (p=0.031; p=0.157).

Conclusions: Visual perceptual learning using Gabor Patches resulted in a significant improvement in near and distance visual acuity, which allowed 23% of patients to achieve a driving license BCVA. A corresponding improvement in stereopsis was noted, and 88% of patients with no binocularity gained it. Further studies will identify which patients will benefit most from this treatment.

Background: There are limited treatment options to improve vision in patients with congenital nystagmus. We examined the use of repeated visual stimulation with Gabor Patches to achieve that goal.

Methods: In a prospective randomized (3:1) controlled open label study, patients aged 9-55 years with congenital nystagmus and best corrected visual acuity (BCVA) between 20/40–20/200 were included. The treatment group underwent visual stimulation for four months, controls were treated with sham stimuli. BCVA, contrast sensitivity, and stereoacuity were assessed.

Results: 26 patients were treated and 10 served as control. Mean age was 22.47±12 years. 6/26 (23%) of treatment subjects achieved driving license BCVA (20/40) vs 1/10 (10%) of controls. Distance treated BCVA improved by 0.10±0.07 logMAR (one ETDRS line) compared with 0.015±0.09 logMAR in controls (p=0.006). Near BCVA improved by 0.16±0.14 logMAR (1.6 ETDRS lines) compared with 0.05±0.13 logMAR in controls (p=0.040). 88% (8/9) of study patients who had no binocularity prior to treatment achieved binocularity (mean 630’) as opposed to 25% (1/4) of controls (p=0.10). Mean stereoacuity and contrast sensitivity improved by 801±730’ and 292±391% in the study group as opposed to 246±376’ and 152±67% in controls respectively (p=0.031; p=0.157).

Conclusions: Visual perceptual learning using Gabor Patches resulted in a significant improvement in near and distance visual acuity, which allowed 23% of patients to achieve a driving license BCVA. A corresponding improvement in stereopsis was noted, and 88% of patients with no binocularity gained it. Further studies will identify which patients will benefit most from this treatment.