Relationship between aneurysm flow pattern type and various anatomic characteristics
| Flow Pattern | Type I | Type II | Type III | Type IV |
|---|---|---|---|---|
| Morphology | ||||
| Lateral | 15 | 4 | 2 | 4 |
| Bifurcation | 5 | 4 | 3 | 4 |
| Terminal | 6 | 1 | 5 | 3 |
| Fusiform | 0 | 2 | 0 | 1 |
| Lobulation | ||||
| Single | 23 | 5 | 6 | 5 |
| Multiple | 3 | 6 | 4 | 7 |
| Size | ||||
| Small | 15 | 2 | 0 | 1 |
| Medium | 10 | 8 | 10 | 5 |
| Large | 1 | 1 | 0 | 6 |
| Aspect ratio | ||||
| Small | 19 | 4 | 8 | 8 |
| Large | 7 | 7 | 2 | 4 |
| Location | ||||
| ICA | 14 | 4 | 0 | 4 |
| MCA | 4 | 3 | 6 | 1 |
| Pcom | 3 | 0 | 4 | 6 |
| ACA | 1 | 0 | 0 | 0 |
| Posterior | 4 | 4 | 0 | 1 |
Note.—ICA indicates internal carotid artery; MCA, middle cerebral artery; Pcom, posterior communicating artery; ACA, anterior cerebral artery.