Effect of Disease Progression on the PRL Location in Patients With Bilateral Central Vision Loss

PURPOSE: To investigate the effect of disease progression on the monocular preferred retinal locus (PRL) of the better eye (BE) and worse eye (WE) of patients with central vision loss. METHODS: Fifty-one patients with bilateral macular diseases were included. The monocular PRL was recorded for each eye (N = 102 eyes) with the MP-1 microperimeter in two visits that were 458 ± 249 days apart. For each eye and visit, the PRL distance from the former fovea, polar angle, and scotoma size were measured. The change in PRL location from visit 1 to visit 2 was evaluated with the differential map analysis. RESULTS: Scotoma size increased significantly in both eyes. The PRL distance from the former fovea increased significantly from visit 1 to visit 2 in the BE, but not in the WE. The polar angle was relatively stable in both visits for the BE. The change in PRL location in the BE was predicted only by the PRL distance from the former fovea in visits 1 and 2, but not by polar angle or scotoma size. For the WE, the change in PRL location depended on the change in PRL location in the BE, rather than on measurements made on that eye. CONCLUSIONS: Disease progression affects monocular PRL location differently in the 2 eyes. The results suggest a recalibration of the oculomotor system with its reference at the PRL from the BE. TRANSLATIONAL RELEVANCE: These findings are important for deciding the course of treatment and/or for developing rehabilitation techniques focusing on PRL relocation.