Magnetic resonance venography results of multiple sclerosis patients and healthy controls
| Patients (n=20) | Controls (n=20) | |
| Intracranial stenosis/occlusion | 4 | 1 |
| Transverse sinus | 2 | – |
| Sigmoid sinus | 2 | 1 |
| Extracranial stenosis/occlusion | 8 | 7 |
| Internal jugular vein | 8 | 7 |
| External jugular vein | 2 | – |
| Alternative drainage | 6 | 5 |
| Final classification | ||
| No evidence of abnormal venous anatomy | 10 | 12 |
| Anomalous venous anatomy | 10 | 8 |
| Possible anomalous venous anatomy | 4 | 3 |
| Probably anomalous venous anatomy | 6 | 5 |