Clinical effectiveness of currently available low-vision devices in glaucoma patients with moderate-to-severe vision loss

PURPOSE: The aim of this trial is to study the effectiveness of currently available low-vision devices in glaucoma patients with moderate-to-severe vision loss. DESIGN: This is a randomized pilot clinical trial. PARTICIPANTS: Sixteen low-vision glaucoma patients participated in this study. METHODS: Patients with a best-corrected visual acuity between 20/70 and 20/400 in the better eye and a diagnosis of stable primary or secondary open-angle glaucoma were randomized to a low-vision treatment group or a nonintervention control group. A telephone interview was conducted before and after the 4-week testing period to assess functional vision. Patients placed in the treatment group received a low-vision examination and used various currently available low-vision aids. Patients placed in the control group received a low-vision examination only. Changes in patients’ reading ability and overall visual ability were chosen as the primary outcomes. Other visual functioning domains (mobility, visual information processing and visual motor skills) were considered as secondary outcomes. RESULTS: Ten patients in the treatment group showed a significant improvement in reading ability and overall visual ability compared to the control group. The difference in mean score for reading ability was 2.52 logits (2.02; P<0.05) and overall visual ability was 0.78 logits (0.64; P<0.05). However, no significant improvement was noted in the other visual functioning domains involving mobility and visual motor skills. CONCLUSION: Currently available low-vision devices primarily enhance central vision with limited benefits to functional activities relying on peripheral vision.