Color Doppler imaging of the retrobulbar circulation in glaucoma

Color Doppler imaging is a noninvasive technique for investigating the retr obulbar circulation, showing specific retrobulbar vessels Ophthalmology Dep artment, The Royal Victoria Hospital, Belfast, Northern Ireland and measuri ng blood velocity characteristics within these vessels. Color Doppler imagi ng is reproducible and has been used by many investigators to study blood v elocity in die ophthalmic artery, the central retinal artery, and the short posterior ciliary: arteries. The technique has shown statistically signifi cant reductions in the flaw velocities and increases in the resistance indi ces of these vessels in both primary open-angle glaucoma and nor mal tensio n glaucoma in comparison with norlnal cclntr.ol subjects. These changes cor relate with disease severity and asymmetry and illustrate a compromised cir culation in this region. Intraocular pressure and vasospasm have been shown to affect blood flow velocities in the same circulation. This article disc usses studies that have elucidated these changes in various subpopulations of glaucoma subjects in an attempt to determine hemodynamic alterations bet ween these disease types. (C) 1999 by Elsevier Science Inc. All rights rese rved.