Cerebral blood flow measurement by color velocity imaging in radiation-induced carotid stenosis.

Objective: To show whether there is any association between the development of neurologic symptoms and the total cerebral blood flow volume documented by color velocity imaging in patients with carotid stenosis that develops after radiotherapy.

Methods: Twenty-three patients with nasopharyngeal carcinoma (4 female and 19 male; age range, 39-69 years; mean age, 55.6 years) and major extracranial carotid stenosis underwent color velocity imaging. In this group, 8 patients had symptoms of a stroke or transient ischemic attack, and the other 15 patients were asymptomatic. The color velocity imaging results in the symptomatic group were then compared with those in the asymptomatic group.

Results: The cerebral blood flow in the symptomatic group was significantly lower than that in the asymptomatic group (224.1 +/- 89.0 versus 532.5 +/- 89.0 mL/min; P = .001).

Conclusions: Cerebral blood flow as measured by color velocity imaging was lower in the symptomatic group. There is an association between the development of neurologic symptoms and blood flow volume.