Table 2

MRI/MRA, DSA, and duplex sonographic findings in 19 patients with extracranial VADs

Patient NoVADDelay (days)2-150MRIMRADSADuplexMRA follow up (delay)
1L6Mural haematoma V3Stenosis V3-4String sign V3HRSPseudoenlargment2-160 (14 days), recanalisation (12 months)
2RString sign V3Recanalisation (3 months)
3L< 1Mural haematoma V3, luminal thrombis V4Stenosis V3String sign V3, occlusion V4HRSOcclusion (> 12 months)
4L7Normal V3-4Normal V2-4Intimal flap V1NormalNormal (12 months)
5L< 1Luminal thrombus V4Occlusion V1, V4, stenosis V2-3Occlusion VA LHRSRecanalisation (2 weeks)
6R, L14Luminal thrombus BAStenosis V3-4 R, L, occlusion. BA (delay to DSA 14 day)Double lumen V1 L, string sign V2-4 R, occlusion BANo flow L, R
7L5Luminal thrombus V3-4Stenosis V2, occlusion V3-4HRSRecanalisation (> 12 months)
8R3Luminal thrombus V4Stenosis V3, occlusion V4HRSRecanalisation (8 months)
9R< 1Luminal thrombus V3-4Stenosis V2, occlusion V3-4String sign V2-3, occlusion V4HRSRecanalisation (3 months)
10R3Luminal thrombus V4Stenosis V2-3, occlusion V4HRSOcclusion (> 12 months)
11LIntimal flap V2, dissecting aneurysm V2NormalOcclusion (9 months after ligation)
12L< 1Luminal thrombus V3-4Double lumen V2, occlusion V3-4String sign V2, occlusion V3-4 (delay to MRA 1 day)HRSRecanalisation (9 months)
13R5Luminal thrombus V3-4Occlusion V3-4Stenosis V4HRSRecanalisation (12 months)
14L7Luminal thrombus V3-4Stenosis V2, occlusion V3-4Occlusion V3-4 LHRSRecanalisation (> 12 months)
15R7Luminal thrombus V3-4Occlusion V2-4Intimal flap V1, occlusion V2-4No flowOcclusion (> 12 months)
16RIntimal flap V1, dissecting aneurysm V1NormalOcclusion (5 months after ligation)
17L7Mural haematoma V3, luminal thrombus V4Stenosis V3, occlusion V4String sign V3, occlusion V4HRS
18R5Luminal thrombus V3-4Occlusion V3-4String sign V3, occlusion V4HRS
19L< 1Mural haematoma V3Stenosis V3, dissecting aneurysm V3String sign V3, dissecting aneurysm V3NormalDissecting aneurysm (2 weeks)
  • 2-150 Delay = interval from neurological deficit to magnetic resonance examination.

  • 2-160 Pseudoenlargement = on projections the dissected vertebral artery appears wider than the patent lumen on cross sections.

  • MRI = magnetic resonance imaging; MRA = magnetic resonance angiography; DSA = digital subtraction angiography; Duplex = B-mode and Doppler sonography; VAD = vertebral artery dissection; delay = interval from neurological deficit to magnetic resonance examination; HRS = high resistance signal; string sign = irregular stenosis; L = left; R = right; V1-4 = vertebral artery segment; BA = basilar artery.