FIG 4. Relationship between degree of carotid stenosis and postoperative dilatation of the ICA. Percent increase in the diameter of the distal ICA was plotted against the grade of carotid stenosis. Grade of carotid stenosis in a cross-sectional area was estimated by conventional carotid ultrasonography. Diameter of the distal ICA was estimated by TOCU. Dotted line indicates 95% stenosis.