Quantification of blood flow velocity of the internal carotid artery: a comparison between phase- Contrast MRI and Doppler Ultrasound

Noninvasive techniques for quantifying the blood flow velocity profile of the internal carotid artery are clinically valuable. hi this study two modalities most frequently used for blood velocity estimation were compared. In the present study blood flow velocity waveform of the internal carotid artery of a healthy male subject was acquired using phase- contrast MRI and Doppler ultrasound modalities. The Doppler spectrum was denoised and maximum velocity envelope curve was extracted using an automatic MAT LAB program. Furthermore, the phase contrast MRI images were processes and the maximum velocity profile was extracted. The extremum values of two profiles as well as the area under the velocity curves were extracted and compared. Results of the present study showed that the overall pattern of the blood velocity waveforms obtained from two modalities were similar (R=0.84). However, Peak systolic, end diastolic and mean velocities resultant from two modalities have a difference of 7.48, 2.83 and 3.19 cm/s respectively. Our results demonstrated that there is a high correlation between blood velocities resulted from Doppler Ultrasound and Phase- contrast MRI and either techniques can he used for blood flow measurements in the internal carotid artery.