Comparison of patients’ data between SAH and VHM groups
| SAH | VHM | Total | P value | |
| Patients, n | 103 (52.0) | 90 (45.5) | 193 | |
| Lesions, n | 113 (54.3) | 90 (43.3) | 203 | |
| Male sex | 82 (79.6) | 79 (87.8) | 161 (83.4) | 0.184 |
| Median age (IQR) | 52 (46–60) | 59 (51–65) | 56 (47–63) | <0.001 |
| Pretreatment mRS | 0.150 | |||
| 1 | 27 (26.2) | 24 (26.7) | 51 (26.4) | |
| 2 | 41 (39.8) | 22 (24.4) | 63 (32.6) | |
| 3 | 13 (12.6) | 11 (12.2) | 24 (12.4) | |
| 4 | 7 (6.8) | 15 (16.7) | 22 (11.4) | |
| 5 | 15 (14.6) | 18 (20.0) | 33 (17.1) | |
| AVF type | <0.001 | |||
| PMAVF | 1 (0.9) | 1 (1.1) | 2 (1.0) | 1.000 |
| Epidural AVF | 14 (12.4) | 4 (4.4) | 18 (8.9) | 0.048 |
| Paravertebral AVF | 13 (11.5) | 2 (2.2) | 15 (7.4) | 0.012 |
| Radicular AVF | 29 (25.7) | 10 (11.1) | 39 (19.2) | 0.009 |
| Dural AVF | 56 (49.6) | 73 (81.1) | 129 (63.5) | <0.001 |
| Side | 0.422 | |||
| Left | 50 (44.2) | 43 (47.8) | 93 (45.8) | |
| Right | 61 (54.0) | 43 (47.8) | 104 (51.2) | |
| Both | 2 (1.8) | 4 (4.2) | 6 (3.0) | |
| Fistula location | 0.007 | |||
| Foramen magnum | 6 (5.3) | 15 (16.7) | 21 (10.3) | 0.008 |
| C-1 | 78 (69.0) | 63 (70.0) | 141 (69.5) | 0.881 |
| C-2 | 29 (25.7) | 12 (13.3) | 41 (20.2) | 0.030 |
| Arterial feeders | <0.001 | |||
| Dural branch of vertebral artery | 64 (62.1) | 70 (77.8) | 134 (66.0) | 0.019 |
| Radicular artery | 28 (27.2) | 10 (11.1) | 38 (18.7) | 0.005 |
| Anterior spinal artery | 27 (26.2) | 5 (5.6) | 32 (15.8) | <0.001 |
| Lateral spinal artery | 16 (15.5) | 4 (4.4) | 20 (9.9) | 0.012 |
| Posterior inferior cerebellar artery | 3 (2.9) | 2 (2.2) | 5 (2.5) | 1.000 |
| Ascending pharyngeal artery | 6 (5.8) | 14 (15.6) | 20 (9.9) | 0.027 |
| Occipital artery | 2 (1.9) | 6 (6.7) | 8 (3.9) | 0.200 |
| Posterior meningeal artery | 4 (3.9) | 1 (1.1) | 5 (2.5) | 0.450 |
| Middle meningeal artery | 0 (0.0) | 1 (1.1) | 1 (0.5) | 0.466 |
| Direction of the venous drainage | <0.001 | |||
| Ascending intradural | 69 (61.1) | 6 (6.7) | 75 (36.9) | <0.001 |
| Descending intradural | 14 (12.4) | 70 (77.8) | 84 (41.4) | <0.001 |
| Bidirectional intradural | 14 (12.4) | 10 (11.1) | 24 (11.8) | 0.779 |
| Epidural | 16 (14.2) | 2 (2.2) | 18 (8.9) | 0.003 |
| Paravertebral venous plexus | 0 (0.0) | 2 (2.2) | 2 (1.0) | 0.195 |
| Aneurysmal structure | 47 (45.6) | 13 (14.4) | 60 (29.6) | <0.001 |
| Varix | 66 (64.1) | 66 (73.3) | 132 (65.0) | 0.168 |
| Treatment | 0.351 | |||
| Conservative | 3 (2.9) | 1 (1.1) | 4 (2.0) | |
| Surgery | 76 (73.8) | 73 (81.1) | 149 (73.4) | |
| Embolisation | 6 (5.8) | 7 (7.8) | 13 (6.4) | |
| Embolisation+surgery | 18 (17.5) | 9 (10.0) | 27 (13.3) | |
| Complications | 20 (19.4) | 14 (15.6) | 34 (16.7) | 0.482 |
| Recurrence | 3 (2.9) | 5 (4.4) | 8 (3.9) | 0.578 |
| Post-treatment modified Rankin Scale (mRS)* | <0.001 | |||
| 0 | 49 (47.6) | 14 (15.6) | 63 (31.0) | |
| 1 | 46 (44.7) | 30 (33.3) | 76 (37.4) | |
| 2 | 1 (1.0) | 10 (11.1) | 11 (5.4) | |
| 3 | 1 (1.0) | 12 (13.3) | 13 (6.4) | |
| 4 | 3 (2.9) | 11 (12.2) | 14 (6.9) | |
| 5 | 0 (0.0) | 5 (5.6) | 5 (2.5) | |
| 6 | 3 (2.9) | 8 (8.9) | 11 (5.4) |
Values are shown as the number (%) of patients or lesions, unless indicated otherwise.
*Post-treatment mRS was evaluated according to the last follow-up.
AVF, arteriovenous fistula; C, cervical; SAH, subarachnoid haemorrhage; VHM, venous hypertensive myelopathy.