Ocular blood flow in normal tension glaucoma and primary open angle glaucoma

Abstract

Objectives: The purpose of the study was to study the ocular blood flow (OBF) in primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG) by color Doppler imaging (CDI) in the ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary artery (PCA) and to correlate this with structural and functional damage in glaucoma. Materials and Methods: This was a cross-sectional and observational study. This was a cross-sectional study, in which 30 eyes of each group and controls were studied, CDI was done by a single observer for all cases. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI) were calculated for OA, CRA, and PCA. Visual fields and retinal nerve fiber layer (RNFL) analysis were done. Results: PSVs and EDVs were lower and RIs were higher for CRA and PCA of NTG and POAG compared to those of controls. The severity of glaucoma (visual field defect) increased when RI of OA was increased in NTG. No such relationship was established between RNFL thinning and OBF. Conclusion: Reduction in PSV and EDV leads to increased RI which is one of the contributory factors in the functional damage in NTG.