Purpose: To evaluate topographic changes in normal-tension glaucoma using serial optic disc images obtained by scanning laser tomography.
Subjects and methods: Fifty-six eyes of 30 patients with normal-tension glaucoma were imaged using the Heidelberg Retina Tomography (HRT) four or more times during follow-up periods of more than 3 years. Disc progression was determined by regression analysis of global and segmental changes in optic disc parameters. Visual field progression was determined by Humphrey Field Analyzer (HFA) program 30-2 and was compared with disc progression.
Results: The global parameters of the optic disc showed progression in 21 of 56 eyes(37.5%). Progression was found in 30 eyes(53.6%) at the superotemporal segment, in 24 eyes(42.9%) at the temporal segment, in 27 eyes(48.2%) at the inferotemporal segment, in 21 eyes(37.5%) at the superonasal segment, in 23 eyes(41.1%) at the nasal segment, and in 27 eyes(48.2%) at the inferonasal segment. The visual field showed progression in 19 eyes (33.9%). The progression in the optic disc parameters did not necessarily agree with that in the visual field.
Conclusions: Glaucomatous disc changes over time can be determined with HRT using regression analysis.