Incomplete Retinal Pigment Epithelium and Outer Retinal Atrophy Characterized Using Fundus Autofluorescence: An...

Area of Science:

• Ophthalmology
• Retinal Imaging
• Medical Diagnostics

Background:

• Incomplete retinal pigment epithelial and outer retina atrophy (iRORA) is a key stage in retinal degeneration.
• Understanding the fundus autofluorescence (FAF) characteristics of iRORA is crucial for predicting disease progression.

Purpose of the Study:

• To correlate fundus autofluorescence (FAF) patterns with incomplete retinal pigment epithelial and outer retina atrophy (iRORA) identified by optical coherence tomography (OCT).
• To investigate the association between FAF characteristics and the progression of iRORA to complete lesions (cRORA).

Main Methods:

• A post hoc analysis of the GATHER2 study (NCT04435366) involving eyes treated with avacincaptad pegol or sham.
• Optical coherence tomography (OCT) was used to define iRORA and track its progression to cRORA over 18 months.
• Fundus autofluorescence (FAF) patterns (none, not classifiable, increased autofluorescence, questionably decreased, definite decreased) were assessed for each lesion.

Main Results:

• At baseline, most identified iRORA lesions showed no FAF abnormalities or questionably decreased autofluorescence (QDAF).
• By month 18, the proportion of iRORA with QDAF and definite decreased autofluorescence (DDAF) increased, while lesions with no FAF abnormalities decreased.
• iRORA lesions that progressed to cRORA were more likely to exhibit increased autofluorescence (IAF), QDAF, or DDAF patterns.

Conclusions:

• FAF characteristics of iRORA are heterogeneous, indicating diverse underlying pathological processes.
• The multimodal phenotype, combining OCT and FAF, provides insights into the progression of retinal atrophy over time.