Table 2.

Site of Occlusion/Abnormality for Typical and Atypical Groups

Typical PresentationsProportion, %Atypical PresentationsProportion, %
LVO*
  Extracranial ICA3/35.92/16.5/3.2
  Intracranial ICA5/59.81/13.2/3.2
  Tandem occlusion1/12.01/03.2/0
  M1 MCA35/3568.65/216.1/6.5
  M2 proximal MCA6/611.718/1158.1/35.5
  Dissection1/12.000
  ICAD003/19.7/3.2
  Stent occlusion ICA001/13.2/3.2
 Total5110031100
Non-LVO
 M2 distal MCA92.100
 M3/M4 MCA or ACA7116.4510.0
 Subcortical255.848.0
 Basilar10.224.0
 Other posterior286.500
Stroke NI306.900
TIA4911.300
ICH276.23264.0
Stroke mimics19344.6714.0
Total43310050100
  • ICA indicates internal carotid artery; ICAD, intracranial atherosclerotic disease; ICH, intracerebral hemorrhage; LVO, large vessel occlusion; MCA, middle cerebral artery; NIHSS, National Institutes of Health Stroke Scale; Stroke NI, stroke diagnosis with no abnormality on imaging; and TIA, transient ischemic attack.

  • * Reported as total number/number with NIHSS ≥6.

  • Includes infarcts in vertebral, superior/inferior cerebellar, and posterior cerebral arterial territories.