[Effect of Morphological and Functional Parameters on Ocular Pulse Amplitudes: An Analysis in Ocular Hypertension and Different Types of Glaucoma].

Background and Purpose: Ocular blood flow imbalance and the loss of autoregulation are widely believed to be important factors in the pathogenesis of glaucoma. The purpose of this study was to investigate the impact of morphometric and functional changes on ocular pulse amplitude (OPA) in normal tension glaucoma (NTG), primary open-angle glaucoma (POAG), pseudoexfoliation-glaucoma (PEX) and ocular hypertension (OHT). Patients and

Methods

This prospective study included 172 patients with manifest glaucoma and OHT. All patients were examined with dynamic contour tonometry (DCT), Goldmann applanation tonometry (GAT), Heidelberg retina tomography II (HRT), and Octopus visual field analysis (program 30II). In order to identify potential determinants of OPA, a generalised linear model (GLM) analysis was defined. As effect sizes, we included gender as a factor and intraocular pressure (measured by DCT [IOP]), optic disc area, cup area, mean deviation (MD), central corneal thickness (CCT), cup-disc ratio (CDR), and patient age as covariates.

Results

Mean OPA was lower in patients with NTG than in other groups. In the generalised linear model in the entire population, a larger OPA was associated with a larger IOP and female gender. In the NTG group, we did not identify effect sizes, whereas, in the OHT group, IOP (measured with DCT) and MD, in the POAG group IOP (measured with DCT) and gender and in the PEX group MD and gender showed a positive effect on OPA.

Conclusions

In this study, we showed that in the NTG group neither demographic nor morphological or functional factors affected OPA. However, in the OHT and POAG groups, OPA was influenced by IOP (measured with DCT), in the OHT and PEX group by MD and in the POAG and PEX groups by gender.