Preferred technique for blood flow volume measurement in cerebrovascular disease.

BACKGROUND AND PURPOSE A noninvasive reliable technique that can reveal cerebral blood flow volume could be a valuable tool in screening programs for stroke prevention. In diagnostic ultrasonography, spectral Doppler imaging (SDI) is popular among sonologists and vascular technologists to estimate blood flow volume despite its documented inaccuracy and the availability of the more accurate technique of color velocity imaging (CVI). The aim of the present study was to demonstrate the discrepancy of blood flow volume estimation with CVI and SDI with use of an "internal" standard. METHODS The common, internal, and external carotid arteries of 50 healthy subjects (22 men, 28 women, age range 19 to 54 years) were examined with CVI and SDI. The total blood flow volume of the internal and external carotid arteries was then compared with the ipsilateral common carotid artery flow. An accurate technique would demonstrate no difference. The difference (expressed as a percent inconsistency) was therefore a measure of the accuracy of the method. RESULTS The mean+/-SD inconsistency was found to be 10.6+/-8.3% for CVI and 27.9+/-14.3% for SDI. The difference in inconsistency between CVI and SDI in measurement of carotid blood flow volume was statistically significant (P<0.01). CONCLUSIONS CVI is more accurate than SDI in the determination of blood flow volume in the carotid arteries. For noninvasive clinical estimation of cerebrovascular blood flow volume, CVI quantification should be the preferred technique.