Retrobulbar hemodynamic parameters in pseudoexfoliation syndrome and pseudoexfoliative glaucoma

Objective To compare the hemodynamic parameters in the retrobulbar vessels in pseudoexfoliative syndrome (PXS), pseudoexfoliative glaucoma (PXG), and age-matched healthy subjects by using color Doppler imaging (CDI). Subjects and methods 72 eyes from 72 patients with PXS, 70 eyes from 70 patients with PXG, and 66 eyes from 66 age-matched healthy subjects who met the inclusion/exclusion criteria were included in this prospective cross-sectional study. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and Pourcelot resistance index (RI) were assessed in the ophthalmic artery (OA), central retinal artery (CRA), and temporal short-posterior ciliary arteries (SPCA). Visual function was assessed using the 24-2 Swedish Interactive Threshold Algorithm (SITA). The main outcomes of the study were PSV, EDV and RI in the OA, SPCA, and CRA. Results The EDV in the OA, SPCA and the CRA was decreased significantly (p<0.001, <0.001, and 0.003 respectively) in the eyes of PXG patients compared with controls and PSX respectively. The RI in the OA, SPCA, and the CRA was significantly higher (p=0.022, 0.005, and 0.007 respectively) in the eyes of PXG patients compared with healthy controls and PSX patients respectively. The mean difference in mean EDV in the OA between the control group and the PXS was 0.18 cm/s, 95% confidence interval (CI) -0.60 to 0.95, p=0.661. The mean difference in mean EDV in the SPCA between the control healthy subjects and the pseudoexfoliative subjects was -0.18 cm/s, 95% CI -0.45 to 0.08, p=0.176. Multivariate regression analysis showed that in the PXG patients the PSV and EDV in the CRA were significantly positively correlated with the mean defect (p=0.006 and 0.002 respectively). The RI in the CRA was significantly negatively correlated with the mean defect in PXG patients, p=0.009. Conclusion The results of this study showed that the retrobulbar hemodynamics might be disturbed in patients with PXG, especially in the central retinal artery. Our results have found no significant differences in the retrobulbar hemodynamic parameters between pseudoexfoliative syndrome patients and age-matched healthy subjects.