Study: OCTa detects choriocapillaris blood flow impairments before nascent GA

Results of a recent prospective, longitudinal, observational study showed that significant impairments in choriocapillaris (CC) blood flow could be detected locally prior to the development of nascent geographic atrophy (nGA). The findings provide additional insight into the pathophysiologic changes that occur with atrophy development in age-related macular degeneration (AMD), reported the researchers.

The study assessed the relationship between CC loss and the development of nGA using optical coherence tomography angiography (OCTA) imaging. The study included 105 eyes from 62 participants with bilateral large drusen, without late AMD or nGA at baseline. Participants underwent swept-source OCTA imaging at 6-month intervals. CC flow deficit percentage (FD%) and drusen volume measurements were taken for the visit prior to nGA development or the second-to-last visit if nGA did not develop. Global and local analyses within superpixels (120 × 120-µm regions), were performed to examine the association between CC FD% and future nGA development.

A total of 15 (14%) eyes from 12 (19%) participants developed nGA. No significant differences were found in global CC FD% at the visit prior to nGA development between eyes that developed nGA and those that did not. CC FD% was significantly higher in superpixels that subsequently developed nGA, and a model using CC FD% was significantly better at predicting foci of future nGA development at the superpixel level than a model using drusen volume alone.

Reference
Greig EC, Moult EM, Despotovic IN, et al. Assessment of choriocapillaris flow prior to nascent geographic atrophy development using optical coherence tomography angiography. Invest Ophthalmol Vis Sci. 2024;65(1):33. doi:10.1167/iovs.65.1.33

This content is independent editorial sponsored by Astellas. Astellas had no input in the development of this content.