Blood-flow Velocities of the Extraocular Vessels in Patients with High-tension and Normal-tension Primary Open-angle Glaucoma

Purpose: To evaluate blood-flow parameters in three different groups of patients with primary open-angle glaucoma.

Methods: Hemodynamic parameters in the ophthalmic artery, central retinal artery, central retinal vein, and lateral and medial short posterior ciliary arteries were evaluated by color Doppler imaging in 237 patients with primary open-angle glaucoma and 124 age-matched normal control subjects. Group A consisted of 56 patients with primary open-angle glaucoma with treated intraocular pressure higher than 20 mm Hg; group B, of 103 patients with primary open-angle glaucoma with progression of glaucomatous damage despite intraocular pressure of 21 mm Hg or less; and group C, of 78 patients with normal-tension glaucoma.

Results: All patients showed a significant decrease in end-diastolic velocities (P < .01) and a significant increase in resistivity index (P < .05) in all arteries measured. Peak-systolic velocities were normal in the ophthalmic artery in all three groups. In the central retinal artery and the short posterior ciliary arteries, however, patients in groups B and C had significantly reduced peak-systolic velocity (P < .05) compared with normal control subjects. Peak-systolic velocity in group A did not differ significantly from that of normal control subjects. Maximal and minimal blood-flow velocities in the central retinal vein were significantly lower in groups B and C (P < .001) compared with normal control subjects. In group A, only minimal blood-flow velocity was significantly reduced (P < .05).

Conclusions: Hemodynamic parameters in the extraocular vessels are altered in patients with glaucoma. Reduced blood-flow velocities may be secondary as well as contributory to glaucomatous damage.