Eccentric viewing training and mobility rehabilitation for a patient with Stargardt disease: A case report

Abstract

Stargardt disease is a progressive inherited retinal disorder leading to central vision loss, significantly affecting daily activities such as reading, facial recognition, and mobility. While no cure exists, vision rehabilitation strategies, including biofeedback microperimetry and eccentric viewing training, have been shown to enhance functional vision by optimizing fixation stability and improving spatial awareness. This case report presents a 24-year-old female university student diagnosed with Stargardt disease, experiencing progressive central vision impairment over 5 years. She reported challenges in reading, academic activities, and independent navigation in crowded environments. Clinical evaluation revealed a visual acuity of 6/18 in the right eye and 6/24 in the left eye, with central scotomas confirmed by Amsler Grid testing and microperimetry, which showed a 5° diameter central scotoma bilaterally and fixation instability in the right eye (P1 = 22%). A structured rehabilitation program consisting of 10 sessions of biofeedback microperimetry preferred retinal locus (PRL) fixation training and mobility training was implemented to improve fixation control and navigation skills. Following the intervention, the patient demonstrated gradual improvement in fixation steadiness, with most fixations concentrated within 2° of vision, and a corresponding improvement in visual acuity to 6/12 + 1. Mobility training further enhanced her confidence in independent navigation and obstacle avoidance. This case highlights the effectiveness of biofeedback microperimetry PRL training and mobility rehabilitation in patients with Stargardt disease. Structured interventions can significantly improve fixation stability, enhance reading performance, and promote independent mobility, ultimately leading to a better quality of life.