Mean velocity data derived from TCCS and grouped according to stenosis assessed by angiography
| Factor | ≥70% Stenosis in C1 (n = 7) | <70% Stenosis in C1 (n = 59) | P Value | ≥50% Stenosis in C1 (n = 8) | <50% Stenosis in C1 (n = 58) | P Value |
|---|---|---|---|---|---|---|
| C1 PSV | 256.3 ± 84.5 | 82.9 ± 37.8 | .0001 | 229.5 ± 109.0 | 83.7 ± 37.7 | .001 |
| C1 EDV | 146.4 ± 72.5 | 29.1 ± 18.2 | .0001 | 129.1 ± 83.0 | 29.4 ± 18.1 | .001 |
| C1 MFV | 178.5 ± 69.3 | 47.0 ± 23.5 | .0001 | 158.6 ± 85.4 | 47.5 ± 23.3 | .001 |
| C1 PI | 0.62 ± 0.20 | 1.13 ± 0.4 | .001 | 0.72 ± 0.34 | 1.13 ± 0.4 | .005 |
| C1 RI | 0.42 ± 0.10 | 0.61 ± 0.13 | .001 | 0.45 ± 0.13 | 0.61 ± 0.13 | .004 |
| C5 PSV | 21.8 ± 5.5 | 48.2 ± 22.1 | .0001 | 21.2 ± 5.3 | 48.8 ± 21.9 | .0001 |
| C5 EDV | 12.2 ± 4.4 | 16.3 ± 8.0 | .21 | 11.4 ± 4.5 | 16.4 ± 7.9 | .07 |
| C5 MFV | 15.4 ± 4.6 | 26.9 ± 11.8 | .005 | 14.7 ± 4.6 | 27.2 ± 11.7 | .001 |
| C5 PI | 0.66 ± 0.22 | 1.16 ± 0.39 | .001 | 0.70 ± 0.22 | 1.17 ± 0.40 | .001 |
| C5 RI | 0.45 ± 0.11 | 0.63 ± 0.12 | .001 | 0.46 ± 0.11 | 0.63 ± 0.12 | .001 |
| C1/M1 | 2.11 ± 1.9 | 0.82 ± 0.34 | .008 | 1.89 ± 1.9 | 0.82 ± 0.34 | .05 |
| C1/ICA | 7.06 ± 6.1 | 1.27 ± 1.2 | .0001 | 6.28 ± 6.1 | 1.27 ± 1.2 | .001 |
| C1/CCA | 5.48 ± 2.1 | 1.68 ± 0.9 | .0001 | 4.87 ± 2.6 | 1.70 ± 0.9 | .001 |
| C5/M1 | 0.17 ± 0.10 | 0.48 ± 0.20 | .0001 | 0.17 ± 0.09 | 0.49 ± 0.20 | .0001 |
| C5/ICA | 0.60 ± 0.43 | 0.66 ± 0.47 | .77 | 0.57 ± 0.40 | 0.67 ± 0.47 | .66 |
| C5/CCA | 0.45 ± 0.11 | 0.94 ± 0.39 | .0001 | 0.43 ± 0.11 | 0.94 ± 0.39 | .0001 |
Note:—All velocities are given in centimeters per second. C1/M1, C1/ICA, C1/CCA, C5/M1, C5/ICA, and C5/CCA indicate divisions of mean velocities; C5, the ganglionic segment of the carotid siphon; C1, the distal segment of the carotid siphon; ICA, the distal (submandibular) portion of the extracranial ICA.