Assessment of Low Vision Referrals before and after Establishment of a Low Vision Program at an Academic Medical Center

imageSIGNIFICANCE

We assessed the number of referrals for low vision (LV) services to determine if establishing an LV program at a large academic medical center impacted referral rates. Visual acuity (VA), referral outcome, location, and specialty were examined as factors that could impact referrals.

PURPOSE

This study aimed to identify gaps in the referral process to LV services.

METHODS

Electronic medical records of patients were reviewed to ascertain the referral rate among those who qualified for services, both before (2014 to 2016) and after (2017 to 2019) the establishment of an LV program. The medical records were further subdivided into two categories based on VA in the better-seeing eye: 20/70 to 20/200 and 20/200 to worse vision.

RESULTS

A total of 2014 patient records with VA qualifying for LV services were reviewed. The proportion of patients who had a VA of 20/70 to 20/200 inclusive in their better eye was 91.7%. A majority (89.8%) of patients with VA of 20/70 to 20/200 and 74.4% of patients with VA worse than 20/200 were never referred. Before establishing an LV program, only 2.2% of patients with VA of 20/70 to 20/200 were referred for services on their first visit, which improved to 8% after the program was established (odds ratio [OR], 3.88; 95% confidence interval [CI], 2.37 to 6.33; P

Effects of Perceptual-motor Training on Collision Judgments with Peripheral Prism Expanded Vision

imageSIGNIFICANCE

Peripheral prisms (p-prisms) improve blind-side detection of hazards in hemianopia by shifting the image of the hazard into the intact visual field. Collision judgments can be made accurately after detection by using a gaze shift to fixate the hazard in the prism-free portion of the lens, but this is slow relative to normal peripheral vision. A prior study found that prism adaptation for visual direction did not occur with general wear. We developed a perceptual-motor training regimen that resulted in accurate pointing at p-prism targets after six 1-hour sessions.

PURPOSE

This study aimed to determine if improvements in pointing accuracy from perceptual-motor training generalized to collision judgments during simulated walking.

METHODS

Participants with hemianopia (n = 13) made collision judgments in virtual reality for a person appearing 0.4 to 13.5° from the walking path. Judgments were measured under fixed gaze, requiring collision judgments via the p-prism image only, and free gaze, representing a more natural scenario. Measurements were made without and with p-prisms immediately after fitting, after a 2-week acclimation, after training, and 3 months later. Controls (n = 13) did one visit without p-prisms.

RESULTS

Controls had 100% detection and symmetrically distributed collision judgments for the central 33 and 36% of hazards under fixed gaze and free gaze, respectively. In hemianopia, the seeing side was not different from controls. Blind-side detection was reduced without p-prisms to 40% fixed gaze and 82% free gaze and improved with p-prisms to 99% fixed gaze and 97% free gaze (P