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Abstract #3438 Published in IGR 4-2
Reproducibility of optic disc parameters acquisition in Heidelberg retina tomograph intraobserver and interobserver agreement in measurement of topometric data
Wang W; Chen XChinese Ophthalmic Research 2002; 20: 173-175
OBJECTIVE: To assess the intra- and interobserver agreement of Heidelberg Retina Tomograph (HRT) parameters as a result of different observers' contour line placement. METHODS: Optic disc images from the HRT of 38 eyes of 38 subjects (25 normal individuals and 13 glaucoma patients) were presented to two observers for analysis. The observers traced each disc margin with a contour line and with a circle. Each observer was masked to the contour line tracings of the other observer. The following stereometric parameters were calculated: disc area, cup area, cup/disc area ratio, rim area, cup volume, rim volume and mean retinal nerve fiber layer thickness. Agreement between the two observers and between two separate occasions for one observer was tested for each parameter, using intraclass correlation coefficients (ICCs) and reliability coefficients. RESULTS: Intraobserver agreement was almost perfect for all parameters (ICCs = 0.80 ~ 0.99). Interobserver agreement between the two observers was substantial for disc area, cup area, cup/disc area ratio, rim area and rim volume (ICCs = 0. 81 ~ 0.96) except cup volume (ICC = 0.59) and mean retinal nerve fiber layer thickness (ICC = 0. 50). The reliability coefficients were 0. 66 ~ 0.99. CONCLUSIONS: The perfect intraobserver agreement indicates that the HRT parameters are highly reproducible. The interobserver agreement suggests that the HRT results as defined by the two observers are interchangeable. LA: Chinese
Dr. W. Wang, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu 610041, China
Classification:
2.14 Optic disc (Part of: 2 Anatomical structures in glaucoma)
6.9.1 Laser scanning (Part of: 6 Clinical examination methods > 6.9 Computerized image analysis)
