Glare and Mobility Performance in Glaucoma: A Pilot Study

Glare disability affects patients with moderate and severe glaucoma. Under glare conditions, mobility performances of glaucoma patients are reduced.The aim of this study was to evaluate glare disability and its impact on mobility and orientation in glaucoma patients.Twenty-two glaucoma patients and 12 age-matched control subjects were included. All patients underwent a clinical evaluation of visual function and halo size measurements to determine glare disability with a glare score (GS) of the best eye and worse eye. Mobility was evaluated by 4 mobility courses on an artificial street (StreetLab) under photopic conditions (P) and mesopic conditions with an additional light source in front of the patient to mimic dazzling conditions (M+G). Mobility time, mobility incidents, trajectory segmentation, distance traveled, preferred walking speed on trial (WS) and percentage of preferred walking speed (PPWS) were recorded, and the Nasa task load index (Nasa-TLX) was evaluated.GS of the worse eye and GS of the best eye were significantly higher in glaucoma patients than in the control group (P=0.001 and 0.003). It was significantly different between moderate glaucoma patients and controls (P=0.001 and 0.010, respectively) and between severe glaucoma patients and controls (P=0.049 and 0.016). In locomotion tasks, comparing performance under M+G and P conditions, mobility performance was significantly different concerning mobility time (P=0.010), distance traveled (P=0.008), WS (P=0.007), PPWS (P=0.006), and Nasa-TLX (P=0.017) in the glaucoma group. Under M+G lighting conditions, mobility performance for glaucoma patients was significantly worse than controls with regard to WS (P=0.038), PPWS (P=0.0498), mobility time (P=0.046), and Nasa-TLX (P=0.006).Glare disability was observed in patients with moderate and severe glaucoma and had an impact on their mobility performance.