Cross table of the A1 segment and PcomA flow on MRA and VE-ASL
| MRA | VE-ASL | Total | ||
|---|---|---|---|---|
| No Flow | Normal Flow | Abnormal Flow | ||
| A1 segment | ||||
| No flow | 16 (28.6%) | 0 (0.0%) | 0 (0.0%) | 16 (28.6%) |
| Normal flow | 6 (10.7%) | 32 (57.1%) | 0 (0.0%) | 38 (67.9%) |
| Abnormal flow | 0 (0.0%) | 0 (0.0%) | 2 (3.6%) | 2 (3.6%) |
| Total | 22 (39.3%) | 32 (57.1%) | 2 (3.6%) | 56 (100.0%) |
| PcomA | ||||
| No flow | 24 (42.9%) | 4 (7.1%) | 3 (5.4%) | 31 (55.4%) |
| Normal flow | 3 (5.4%) | 16 (28.6%) | 0 (0.0%) | 19 (33.9%) |
| Abnormal flow | 0 (0.0%) | 0 (0.0%) | 6 (10.7%) | 6 (10.7%) |
| Total | 27 (48.2%) | 20 (35.7%) | 9 (16.1%) | 56 (100.0%) |
Note:—PcomA indicates posterior communicating artery; MRA, MR angiography; VE-ASL, vessel-encoded arterial spin-labeling.