Abstract
Purpose: Designing and evaluating a new test to assess the ability to scan for peripheral objects in tunnel vision (TV) patients. Methods: Twenty patients with retinitis pigmentosa were recruited and the TV were also simulated in another 50 healthy participants (SIPs). Both groups searched for randomly-located targets within a field of view (FoV) of 60°. The detection time (DT) for each target was recorded. Head and eye movements were allowed and presentation time was unlimited. The test's validity was investigated by correlating DT with the percentage preferred walking speed (PPWS) and collisions on an indoor mobility course. Result: In both groups, the remaining FoV ranged from 4° to 22 degrees. DT scores were significantly correlated with target location (p <0.05), and inversely correlated with FoV (p <0.05). In the patients with TV, a moderate relationship was found between the DT and mobility scores (r = 0.30), but did not reach statistical significance ( p>0.05). In SIPs, there was a highly significant relationship with both PPWS (r = −0.50 to −0.60; p <0.0001), and collisions (r = 0.40 to 0.50; p <0.0001). Conclusion: The test is unique in design, simple to perform, conducted in a relatively short time (5–10 minutes) and have demonstrated to be sensitive and valid. This new test could be considered while assessing the efficacy of optical aids for those patients.