Relationship between ocular perfusion pressure and retrobulbar blood flow in patients with glaucoma with progressive damage

PURPOSE: To evaluate the relationship between ocular perfusion pressure and color Doppler measurements in patients with glaucoma. MATERIALS AND METHODS: Twenty patients with primary open-angle glaucoma wit h visual field deterioration in spite of an intraocular pressure lowered be low 21 mm Hg, 20 age-matched patients with glaucoma with stable visual fiel ds, and 20 age-matched healthy controls were recruited. After a 20-minute r est in a supine position, intraocular pressure and color Doppler measuremen ts parameters of the ophthalmic artery and the central retinal artery were obtained, Correlations be tween mean ocular perfusion pressure and color Do ppler measurements parameters were determined. RESULTS: Patients with glaucoma showed a higher intraocular pressure (P < . 0008) and a lower mean ocular perfusion pressure (P < .0045) compared with healthy subjects. Patients with deteriorating glaucoma showed a lower mean blood pressure (P = .033) and a lower end diastolic velocity in the central retinal artery (P = .0093) compared with normals, Mean ocular perfusion pr essure correlated positively with end diastolic velocity in the ophthalmic artery (R = 0.66, P = .002) and central retinal artery (R = 0.74, P < .0001 ) and negatively viith resistivity index in the ophthalmic artery (R = -0.7 0, P = .001) and central retinal artery (R = -0.62, P = .003) in patients w ith deteriorating glaucoma. Such correlations did not occur in patients wit h glaucoma with stable visual fields or in normal subjects, The correlation s were statistically significantly different between the study groups (para llelism of regression lines in an analysis of covariance model) for end dia stolic velocity (P = .001) and resistivity index (P = .0001) in the ophthal mic artery, as well as for end diastolic velocity (P = .0009) and resistivi ty index (P = .001) in the central retinal artery. CONCLUSIONS: The present findings suggest that alterations in ocular blood flow regulation may contribute to the progression in glaucomatous damage. ( C) 2000 by Elsevier Science Inc, All rights reserved.