Optical Coherence Tomography Angiography in CRB1-Associated Retinal Dystrophies

Aim of the study: To report optical coherence tomography angiography (OCTA) findings in patients affected by CRB1-associated retinal dystrophies. Method: Patients affected by a genetically confirmed CRB1-associated retinal dystrophy were prospectively enrolled in an observational study, along with age- and sex-matched healthy volunteers as control subjects. All study and control subjects received a complete ophthalmic examination and multimodal retinal imaging, including OCTA. Result: A total of 12 eyes from 6 patients were included in the study. The mean BCVA of patients was 0.42 +/- 0.25 logMAR. Two patients showed large central atrophy, with corresponding definite hypo-autofluorescence on fundus autofluorescence (FAF). Another four patients disclosed different degrees of RPE mottling, with uneven FAF. On OCTA, the macular deep capillary plexus and choriocapillaris had a lower vessel density in eyes affected by CRB1-associated retinopathy when compared to healthy controls. On the other hand, vessel density at the peripapillary radial capillary plexus, superficial capillary plexus, and deep capillary plexus was significantly altered with respect to control eyes. Statistical analyses disclosed a negative correlation between the deep capillary plexus and both LogMAR best corrected visual acuity and central retinal thickness. Conclusion: Our study reveals that CRB1-associated retinal dystrophies are characterized by vascular alterations both in the macular and peripapillary region, as assessed by OCTA.