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Abstract #26661 Published in IGR 12-3
Evaluation of scanning protocols for imaging the anterior chamber angle with anterior segment-optical coherence tomography
Khor W-B; Sakata LM; Friedman DS; Narayanaswamy A; Lavanya R; Perera SA; Aung TJournal of Glaucoma 2010; 19: 365-368
Purpose: To evaluate different anterior segment-optical coherence tomography (AS-OCT) scanning protocols for detecting eyes with angle closure. Methods: This cross-sectional study enrolled 2104 subjects from a community clinic in Singapore. All participants underwent AS-OCT imaging in the dark (Visante, Carl-Zeiss, Meditec, Dublin, CA), and gonioscopy with a Goldmann 2-mirror and a Sussman lens by an experienced examiner. The anterior chamber angle in a particular quadrant was considered closed on gonioscopy if the posterior trabecular meshwork could not be seen; and on AS-OCT by the presence of contact between the iris and angle wall anterior to the scleral spur. Protocols using combinations of AS-OCT scans of different quadrants of the eye were compared. Results: A total of 1853/2104 right eyes could be graded in all 4 quadrants. In all, 380 (20.5%) eyes had closed angles in at least 2 quadrants on gonioscopy. The AS-OCT scanning protocol that only imaged the inferior quadrant showed the best area under the receiving operating characteristic curve (AUC 0.76, sensitivity 84%, specificity 69%) for detecting angle closure. Although technically easier to obtain, the protocol that only included the nasal-temporal quadrants had the lowest AUC (AUC 0.67, sensitivity 47%, specificity 88%), whereas scanning the superior-inferior quadrants showed high sensitivity for detecting angle closure (92%), but low specificity (54%). Conclusions: Using the results obtained in a research setting, the diagnostic performance of AS-OCT varied according to the adopted scanning protocol. The inferior quadrant-only protocol showed the best diagnostic performance but the low specificity would limit its use for population screening.
T. Aung. Singapore Eye Research Institute, Singapore National Eye Center, 11 Third Hospital, Avenue, 168751, Singapore. tin11@pacific.net.sg
Classification:
6.9.2.1 Anterior (Part of: 6 Clinical examination methods > 6.9 Computerized image analysis > 6.9.2 Optical coherence tomography)
