Doppler ultrasonography of ocular blood flow in non-glaucoma versus primary open angle glaucoma subjects at the university of Nigeria teaching hospital, Enugu

Abstract

Purpose: To evaluate and compare the ocular blood flow in non-glaucoma versus primary open-angle glaucoma (POAG) subjects attending the ophthalmic clinic of University of Nigeria Teaching Hospital (UNTH) Enugu using Doppler ultrasonography. Methods: A cross-sectional comparative study was adopted. Fifty-Eight POAG and 58 non-glaucoma subjects were recruited. Information on their socio-demographic and clinical profiles was obtained via an interviewer-administered questionnaire. Ocular Doppler Imaging was performed on all the Subjects. Peak systolic volume, End diastolic volume, mean flow velocity and Resistive Index (RI) of the central retinal artery and ophthalmic artery were recorded. Data were analysed using the SPSS version 21. Person correlation was used to determine the relationship between the Doppler indices and demographic and clinical variables. The level of significance was at p <0.05. Results: The subjects were mainly males, 71(61.7%), with an age range of 40 to 79 years. The POAG Subjects lived with glaucoma for 5.57±4.2 years, and mainly on medical treatment 52(89.7%) with beta-blockers and prostaglandin analogues. The RI was significantly higher (p=0.01) in POAG subjects. A significant positive relationship (P = 0.014) was observed between RI and intraocular pressure (IOP) of the POAG subjects. Conclusion: In POAG subjects, RI was significantly higher; as the IOP increased there was an increase in RI translating to a sub-optimal ocular blood flow. Interventions aimed at modifying the RI would therefore be synergistic with IOP lowering measures. Additionally, RI assessment may offer a new target for glaucoma case finding.