Fig 1. A, Flow volume measurement of internal carotid artery by different sonographic techniques and MR phase-contrast imaging in a healthy 29-year-old man. With CDI, the vessel diameter at the area of interest was measured as 0.46 mm and the flow volume was calculated as 294.99 mL/min.

B, The flow volume measurement with PDI from the same segment as panel A. The vessel diameter was measured as 0.48 mm and blood-flow volume was calculated as 317.92 mL/min.

C, The flow volume measurement obtained with BFI revealed the lowest values. The vessel diameter was measured as 0.45 mm and blood-flow volume was calculated as 260.56 mL/min.

D, MR phase-contrast flow quantification (TR/TE, 29/7.7) of the same internal carotid artery revealed a blood-flow volume of 246.9 mL/min.