This study aims to prepare for the first-in-human clinical trial of cone optogenetics vision restoration. As a first step, this worldwide multicenter ocular imaging study (EyeConic Study) is performed to identify eligible patients.

In a subset of patients with inherited retinal dystrophies (IRDs), cones lose their light-sensitive outer segments but remain alive in a dormant stage. This creates an opportunity to resensitize them through targeted optogenetic tools. However, the true proportion of low vision patients harboring dormant, non-functional cones, is currently unknown. The worldwide multicenter retrospective study (EyeConic) aims to estimate the proportion of low vision patients with remaining cone cell bodies for the first time.

Inclusion Criteria (patients):

• Diagnosis of generalized IRD
• Low vision as defined as visual acuity worse or equal to 0.05 (or 20/400) in the study eye
• Availability of macular optical coherence tomography (OCT)

Inclusion Criteria (controls):

• Normal ophthalmic findings
• Availability of macular optical coherence tomography (OCT)

Exclusion Criteria (all):

• Other eye diseases with a significant effect on vision or retinal structure
• Extraocular disease affecting retinal structure such as neurodegenerative diseases

• Patients with diagnosis of generalized retinal dystrophy
• Normal controls