Standardizing Measurement of Complete Retinal Pigment Epithelial and Outer Retinal Atrophy: Classification of Atrophy Meeting Report 8.

PURPOSE: To highlight the role of en face OCT in the measurement of choroidal hypertransmission defects (hyperTDs) in complete retinal pigment epithelial and outer retinal atrophy (cRORA), and to refine the definition of retinal pigment epithelium (RPE)-related alterations associated with cRORA.

DESIGN

Consensus meeting.

PARTICIPANTS

Panel of retina specialists, including retinal imaging experts, reading center leaders, and retinal histologists.

METHODS

As part of the Classification of Atrophy Meeting (CAM) program, an international group of experts analyzed and discussed the role of en face OCT in the assessment of cRORA. A structured study was conducted, consisting of an exercise to assess en face OCT cases, reviewed jointly during the eighth CAM meeting, and to explore the utility of this advanced tool for disease staging and progression. Additionally, definitions previously applied to RPE abnormalities were discussed and refined leading to modifications. The current report summarizes the methods used during the consensus meeting and the outcomes achieved as pertains to the application of en face OCT for cRORA grading and simplification of the RPE assessment criteria.

MAIN OUTCOME MEASURES: Defining the role of en face OCT in the detection and quantification of hyperTDs, improving classification of cRORA, and refining the terminology related to RPE alterations to enhance grading consistency.

RESULTS

During the consensus case discussions, high levels of agreement were achieved for hyperTD detection using en face OCT. The CAM group affirmed the role of en face OCT as a critical adjunct to traditional B-scan analysis, for more precise measurement of the area of cRORA lesions and for distinguishing threshold cRORA from smaller incomplete retinal pigment epithelial and outer retinal atrophy lesions. Additionally, merger of RPE attenuation and RPE disruption into a unified category termed "abnormal RPE band" significantly reduced interreader variability, leading to greater consistency among graders.

CONCLUSIONS

The integration of en face OCT with cross sectional B-scan imaging enhances the accurate classification and area measurement of early atrophic alterations in age-related macular degeneration, improving diagnostic consistency and lesion assessment. The consensus panel's adoption of the abnormal RPE band term as a unified category for RPE abnormalities may reduce confusion regarding the definition of RPE degeneration and has the potential to improve interreader variability.

FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.