Streamlined Ophthalmologist-Led Pathway to Diagnosis and Accessibility of Genetics Testing for Patients with Inherited Retinal Dystrophies in Canada

Objective: To investigate the ability of a new clinical model to improve accessibility and expedite the pathway to molecular diagnosis for patients with suspected inherited retinal diseases (IRDs). Design: Retrospective cohort study of electronic patient records. Participants: All patients referred to general medical genetic clinic between September 2017 and September 2019 and an ophthalmologist-led IRD clinic between October 2021 and July 2023 for suspected IRD were included. Methods: The difference in timeliness and accessibility to diagnosis and genetics testing for patients referred for suspected IRDs were compared based on whether they were referred to a general medical genetics clinic or an ophthalmologist-led IRD clinic. Main Outcome Measures: The primary outcomes were time to consult from referral; time from initial consult to molecular diagnosis; and the time from initial consult to genetics result disclosure and counseling. Secondary outcomes included number of prior providers investigating the chief complaint, the proportion of patients undergoing genetics testing, and the range of diagnostic investigations undertaken. Results: Four hundred seventy-three patients were included, with 212 cases from a general medical genetics clinic and 261 from a medical retina clinic. The mean time from referral to initial consult was 14 months (+/- 3.33 months) and 4 months (+/- 3.4 months) for the general medical genetics and the ophthalmologist-led IRD clinics, respectively. The mean time from initial consult to genetics disclosure and counseling was 6 months (+/- 3.6 months) and 3.5 months (+/- 1.8 months) for the medical genetics and the ophthalmologist-led models, respectively. The total time from initial referral to genetics disclosure and counseling for the medical geneticist-led clinic model was 20 to 24 months. The total time from initial referral to genetics disclosure and counseling for the ophthalmologist-led retinal clinic was 5 to 8 months. The average number of prior providers seen before presenting to the ophthalmologist-led retina clinic was 2.05 (range, 1-10). Conclusions: Shifting from the traditional medical genetics model to the new ophthalmologist-led IRD clinical model may improve accessibility and expedite the pathway to molecular diagnosis and subsequent gene therapy trials for patients with suspected IRDs.