The relationship between retrobulbar blood flow velocity and glaucoma damage. An intraindividual comparison

Abstract

Glaucomatous optic nerve damage is thought to be influenced by ocular perfusion. The aim was to investigate if a difference in visual field and Heidelberg retinal tomography (HRT) between two eyes of an individual glaucoma patient is reflected in different blood flow velocities in retrobulbar vessels. Data from 53 patients including 26 normal tension glaucoma patients (NTG) and 27 high tension glaucoma patients (HTG) were evaluated retrospectively. In 38 patients asymmetric glaucomatous damage (AGD) could be demonstrated by both structural (HRT) and functional measures (static or Goldmann perimetry). In 15 patients there was symmetric glaucomatous damage (SGD). To discriminate between AGD and SGD we used a score for HRT and visual field. Color Doppler imaging (CDI) was performed with a Siemens Quantum 2000. No significant differences were found when comparing group means of intraindividual deviation of CDI in patients with AGD vs. SGD. Overall analysis of CDI values in NTG vs. HTG eyes also showed no significant differences. Nevertheless we measured decreased blood flow velocities for NTG compared to HTG eyes especially in short posterior ciliary arteries, peak systolic and end diastolic velocities. A simple correlation between retrobulbar blood flow velocities and glaucomatous damage could not be found. However, color Doppler images can give important additional information in the diagnosis of glaucoma, especially normal tension glaucoma.