Aims: To study the relation between optic nerve head topography (Heidelberg retina tomograph, HRT) and disc area, visual field index mean defect (MD), and intraocular pressure (IOP), and to see whether change in HRT parameters is associated with change in MD in a prospective follow up.
Methods: 80 consecutive patients (69 patients with exfoliation glaucoma and 11 with ocular hypertension combined with exfoliation syndrome) were examined before IOP reducing intervention and prospectively followed every 6 months for 2 years.
Results: At the entry point, multiple regression analysis showed significant linear association between MD and all HRT parameters, when controlling for disc area. Disc area showed significant association with cup area, cup/disc area ratio, rim area, cup volume, and mean RNFL thickness. Six months after intervention IOP had decreased significantly. Reversible changes in cup area, cup/disc area ratio, rim area, cup volume, rim volume, mean cup depth, and maximum cup depth were associated with decrease in IOP. During the follow up period from 6 month to 2 years, IOP did not change significantly, and MD was used as a measure of progression of glaucoma. During this period, only cup shape measure among HRT parameters showed significant association with subsequent change in MD.
Conclusion: Disc area should be taken into account when using HRT to compare patients. Any effect of change in IOP should be also taken into account when using HRT in follow up. Cup shape measure is a promising indicator of progression of glaucomatous damage.