Identification of potential predictive vascular indicators for primary open angle glaucoma- a case control study

Abstract

Introduction: Glaucoma is the second leading cause of irreversible blindness worldwide and recently a vascular mechanism has been postulated in the pathogenesis of glaucomatous optic nerve damage but the relationship of the various hemodynamic factors and open angle glaucoma is still controversial.

Aim: To compare the intraocular pressure and the different vascular indices among cases and controls; to determine their relationship with primary open angle glaucoma.

Settings and Design: Hospital based case control study.

Methods and Material: The study was undertaken from November 2014 to October 2015 in a tertiary care centre with 200 participants above 40 years comprising of 100 cases of primary open angle glaucoma and a similar number of randomly selected age and sex matched healthy controls. All underwent a detailed comprehensive ocular examination. The blood pressure was measured in each and the variables like systolic - diastolic perfusion pressures, mean arterial and mean ocular perfusion pressures were calculated using the formulas.

Results: Amongst all vascular factors studied, diastolic blood pressure, mean ocular perfusion pressure and intraocular pressure were extremely significant among cases as compared to controls. Those having higher intraocular pressure had higher values of systolic, diastolic and mean arterial pressures and intraocular pressure had a positive correlation with these pressures.

Conclusion: The mean ocular perfusion pressure was very much lower in cases than in controls and thedifference too was highly significant and hence we conclude that along with high intraocular pressure, a vascular mechanism is there behind the occurrence of primary open angle glaucoma.