Friday, April 21, 2017

Background

  • An intimal tear allows blood to enter the arterial wall and separate the intimal layer of the artery from the media, forming a hematoma
  • Most commonly occur in the internal carotid artery 2-3 cm away from the bifurcation of the common carotid
  • Most commonly occurs spontaneously, etiology unknown
  • May also occur in setting of trauma, although vertebral dissection is more common
  • Some with familial connective tissue diseases may be predisposed
  • Will show both luminal narrowing and aneurysmal dilatation on imaging

Radiologic Findings

  • On CT: contast will show double lumen, luminal narrowing, flap formation, and/or aneurysmal dilatation
  • On MR:
    • T1 with fat-suppression will show intramural hematoma as a crescent
    • Hematoma also visualized on T2
    • MRA shows vessel tapering and aneurysmal dilatation 
T1 non-con fat-sat
Dissection_T1fatsat_0726
Dissection_T1fatsag_0726

 

MRA
Dissection_MRA_0726

References

Hakimi R, Sivakumar S. Imaging of Carotid Dissection. Curr Pain Headache Rep. 2019;23(1):2. Published 2019 Jan 19. doi:10.1007/s11916-019-0741-9

Schievink WI. Spontaneous dissection of the carotid and vertebral arteries. N Engl J Med. 2001;344(12):898-906. doi:10.1056/NEJM200103223441206