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Abstract #18487 Published in IGR 3-3
A clinical comparison study of two planimetry methods: conventional versus digital planimetry of optic disc photograph
Nguyen NX; Horn FK; Langenbucher A; Mardin CYKlinische Monatsblätter für Augenheilkunde 2001; 218: 727-732
BACKGROUND: Optic disc size is an important parameter in the diagnosis of glaucomatous and nonglaucomatous optic nerve damage. The aim of this study was to compare quantitative measurements of the optic disc with established conventional planimetry and with a new digital method using Soft imaging system analySIS™ for Ophthalmology, and to determine the reproducibility of this new method. PATIENTS AND METHODS: Fifty color stereo optic disc photographs of 50 patients (mean age, 41.7 ± 13.4 years) were included in the retrospective, comparative study. Conventional and digital planimetry was taken by one skilled examiner in a masked fashion. According to the patient's number, measurement values obtained with both methods were matched. Digital planimetric measurements of ten optic disc photographs were repeated on days 7 and 14. Statistical analysis was carried out using linear regression analysis, reliability coefficient and U test. RESULTS: The planimetric values did not vary significantly between the two methods for optic disc area (3.19 ± 0.65 versus 3.03 ± 0.64 mm2; p = 0.96), cup area (1.36 ± 0.62 versus 1.21 ± 0.63 mm2; p = 0.96), or neuroretinal rim area (1.83 ± 0.38 versus 1.82 ± 0.41 mm2; p = 0.98). Neither was there a significant difference in horizontal or vertical diameter of the optic disc and cup, nor in the diameter of the superior temporal and inferior temporal retinal artery and vein at the optic disc border between the two methods (p < 0.5). Differences between measured values for optic disc, optic cup area, and neuroretinal rim area obtained with both methods were 0.16 ± 0.10 mm2 (range, -0.05 to 0.24), 0.15 ± 0.10 mm2 (range, -0.12 to 0.26), and 0.014 ± 0.11 mm2 (range, -0.26 to 0.26). A high correlation of all planimetric values was observed between both methods (r = 0.9, p < 0.0001). Using digital planimetry, differences between days 1, 7, and 14 were 0.05 ± 0.03 (range, 0.02 to 0.10) mm2 for optic disc, 0.05 ± 0.04 (range, 0.0 to 0.13) mm2 for optic cup area, and 0.05 ± 0.05 (range, 0.01 to 0.14) mm2 for the neuroretinal rim area. The reliability coefficient of digital planimetry was 0.9 for optic disc parameters. CONCLUSIONS: The comparable results between both methods and the high reproducibility suggest that digital planimetry could be used either for clinical routine or scientific evaluation of the optic nerve. LA: German
Dr N.X. Nguyen, Augenklinik mit Poliklinik der Universität Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
Classification:
2.14 Optic disc (Part of: 2 Anatomical structures in glaucoma)