Abstract: Objective To evaluate the feasibility by oblique sagittal T1-weighted (QIR-FSE) black-blood sequence for
measurement of the carotid bifurcation angle. Methods Twenty-three patients undergoing carotid magnetic resonance imaging
(MRI) were divided in normal group and plaque group. Carotid bifurcation angle was measured by both 2D-TOF and oblique
sagittal T1W (QIR-FSE) black-blood sequence, and the measurement was repeated after 3 months to evaluate the
reproducibility. The measurement results using 2D-TOF and oblique sagittal T1W (QIR-FSE) black-blood sequence were
compared to assess the consistency of the two sequences. Four different angles of each carotid artery were measured from
different locations on oblique sagittal T1W. The ratio of the bilateral carotid bifurcation angle (Right/Left) was compared.
Results Ten patients in each group were enrolled after excluding 3 patients. Strong correlations were found between the
results of the first and the second measurements for both 2D-TOF and oblique sagittal T1W sequences. No significant
difference was found between the two sequences in the ratio of bilateral carotid bifurcation angle (right/left), nor in the 4
angles from different locations. Conclusion Oblique sagittal T1-weighted (QIR-FSE) black-blood sequence can be used to
measure the carotid bifurcation angle.