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Abstract #51913 Published in IGR 14-4
Symmetry of optic nerve head parameters measured by the heidelberg retina tomograph 3 in healthy eyes: the blue mountains eye study
Li H; Healey PR; Tariq YM; Teber E; Mitchell PAmerican Journal of Ophthalmology 2013; 155: 518-523.e1
PURPOSE: To assess the symmetry of optic nerve head parameters measured by the Heidelberg Retina Tomograph 3 (HRT 3) between fellow eyes in a normal elderly population. DESIGN: Cross-sectional population-based study. METHODS: Participants of the Blue Mountains Eye Study 10-year follow-up who did not have optic disc disease, including glaucoma, were included. Optic nerve head parameters measured by HRT 3 were compared between fellow eyes. The normal range of interocular asymmetry (larger disc minus smaller disc) was determined by the 2.5th and 97.5th percentiles. RESULTS: A total of 1276 eligible participants had HRT scans of both eyes. HRT measurements in right eyes differed slightly in rim steepness and rim volume from those in left eyes (P < .05). The 2.5th and 97.5th percentile of interocular asymmetry limits were -0.41 and 0.45 for cup-to-disc ratio and -0.19 and 0.22 for cup-to-disc area ratio, respectively. The highest interocular correlation was found in disc area and cup area (r ranged from 0.74-0.76), whereas mean cup depth, cup volume, and retinal nerve fiber layer thickness had the poorest correlation (r ≤ 0.07). Greater optic disc area asymmetry was associated with a larger interocular difference in the other optic nerve head parameters. CONCLUSIONS: There was minimal interocular difference and substantial interocular correlation in optic nerve head parameters measured by HRT 3. Interocular asymmetry greater than 0.2 for cup-to-disc area ratio was considered outside the normal range.
Centre for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, Australia.
Full articleClassification:
6.9.1.1 Confocal Scanning Laser Ophthalmoscopy (Part of: 6 Clinical examination methods > 6.9 Computerized image analysis > 6.9.1 Laser scanning)
