Co-targeting Dysregulated Ocular and Cochlear Blood Flow via Ophthalmic Nerve Stimulation for the Treatment of Type 2 Usher Syndrome: Prospective Case Series

Reduced dysregulated ocular and cochlear blood flow are proposed as common pathways in the pathogenesis of type 2 Usher syndrome (USH2). The purpose of the study was to evaluate the safety and efficacy of ophthalmic nerve stimulation (ONS) combined with ascorbic acid (AA) in treatment of USH2. Nine participants with USH 2, were enrolled in a prospective interventional case series. All participants were daily treated with ONS sessions and intravenous AA for two weeks. The primary efficiency endpoint was 6 months’ changes in scotopic vision as measured by a Low Luminance Questionnaire-10 (LLQ-10) with a maximum score of 100 points. Rod responders were defined by ≥ 25points increment of LLQ-10 score. The results showed that ONS-based therapy significantly improved scotopic vision by 42.1 + 11.3 points ( p = 0.0001 ) and 7 (77.8%) of the participants were identified as rod responders. Additionally, clinically significant improvement visual acuity (≥ 0.2 logMAR) and contrast sensitivity (≥ 0.3 log unit) were noticed in 22.2% of the left eyes. Furthermore, a significant improvement of hearing was subjectively reported by one third of the participants. In conclusion, ONS-based therapy significantly improved night vision in patients with USH2. Additionally, a clinically significant improvement of hearing was noticed in one third of patients.