Prevalence of intracranial arterial stenosis
| Vascular segments | Degree of stenosis | Total | ||
|---|---|---|---|---|
| 30–50% | 50–70% | >70% | ||
| ICA | 18 (16%) | 6 (5%) | 2 (2%) | 26 (23%) |
| MCA | 17 (15%) | 17 (15%) | 8 (7%) | 42 (37%) |
| ACA | 3 (3%) | 0 (0%) | 0 (0%) | 3 (3%) |
| PCA | 21 (18%) | 5 (5%) | 3 (3%) | 29 (25%) |
| Basilar | 2 (2%) | 1 (1%) | 2 (2%) | 5 (4%) |
| Vertebral | 9 (8%) | 0 (0%) | 1 (1%) | 10 (9%) |
| Total | 70 (61%) | 29 (25%) | 16 (14%) | 115 (100%) |
ACA, anterior cerebral artery; IAS: intracranial arterial stenosis ICA, internal carotid artery—in this context the intracranial segment; MCA, middle cerebral artery; PCA, posterior cerebral artery.