Orbital color Doppler imaging in carotid occlusive disease
L. A. Mawn, T. R. Hedges 3rd, W. Rand and P. A. Heggerick
New England Eye Center, Tufts University, Boston, Mass, USA.
OBJECTIVE: To define orbital circulation abnormalities identified by color
Doppler imaging in patients with severe carotid occlusive disease.
PATIENTS: Twenty-four patients referred to a hospital-based
neuro-ophthalmology service with hemodynamically significant carotid
occlusive disease (> 75% stenosis) were prospectively studied. Eight had
signs of ocular ischemic syndrome; 12 of the 24 patients underwent
endarterectomy. MAIN OUTCOME MEASURES: Peak systolic velocity of the
central retinal, posterior ciliary, and ophthalmic artery and pulsatility
indexes as determined by color Doppler imaging. METHODS: Color Doppler
imaging was performed using a 7.5-MHz probe. Both eyes were studied in all
patients and carotid duplex imaging was obtained. RESULTS: All patients
with hemodynamically significant carotid occlusive disease had lower mean
peak systolic velocities in the central retinal, posterior ciliary, and
ophthalmic arteries and higher pulsatility indexes compared with normal
control patients. Endarterectomy improved peak systolic velocities.
Reversal of ophthalmic flow direction as a separate variable was
unassociated with altered mean central retinal or posterior ciliary artery
flow velocities. Patients with ocular ischemic syndrome may have similar
orbital color Doppler imaging findings compared with patients with severe
carotid occlusive disease without overt manifestations of chronic ocular
ischemia. CONCLUSION: Orbital circulation is highly adaptable even when
faced with severe compromise in proximal blood flow.
