Variability across the optic nerve head in scanning laser tomography
- Correspondence to: Professor R A Hitchings, Glaucoma Research Unit, Moorfields Eye Hospital, City Road, London EC1V 2PD, UK; roger.hitchings{at}virgin.net
- Accepted 3 September 2002
Abstract
Aim: To characterise measurement variability in scanning laser tomography of the optic nerve head.
Methods: 21 normal and 21 glaucoma subjects underwent same and separate day test-retest Heidelberg retina tomograph imaging by the same and different operators.
Results: Rim area was most reproducible among parameters. Its variability tended to be highest temporally and increased (p<0.05) with testing involving different operators and visits. Nature of regional variability differed between glaucoma and normal eyes and between standard and 320 μm reference planes.
Conclusions: Rim area is reproducible and potentially useful as a marker of progression. Pattern of variability and the influence of different reference planes, disease, operators, and visits should be considered when evaluating progression.
