Giant Cell Arteritis

GCA is a systemic granulomatous vasculitis involving

  •  most commonly involving the external carotid branches,
    • especially the superior temporal artery
    • cranial arteries
    • vertebral arteries
    • coronary arteries
    • mesenteric arteries
    • aorta 15%
      • annuloaortic ectasia or
      • ascending aortic aneurysm that can extend into the aortic arch
      • acute dissection, aortic valve insufficiency, or abdominal aortic aneurysm
  • most common form of aortitis in North America, accounting for more than 75% of cases

Etiology

PF >50

Result

    • acute phase – destruction of the internal elastic lamina
      • inflammatory cellular infiltrate with multinucleated giant cells and lymphocytes
    • Chronic – fibrosis of the wall
GCA in a 72-year-old woman. Contrast-enhanced CT image shows diffuse abnormal thickening of the thoracic aorta. The thickening was due to an extensive intramural hematoma.
Radiographics Restrepo 2011
GCA in a 65-year-old woman. Contrast-enhanced CT images shows diffuse wall thickening of the thoracic aorta.
Radiographics Restrepo 2011
GCA in a 67-year-old woman. (a) Gradient-echo MR image, obtained at the level of the aortic root, shows abnormal thickening of the middle one-third of the descending aorta (arrow).
Radiographics Restrepo 2011
Fat-suppressed T2-weighted MR image shows increased signal intensity in the aortic wall (arrow), a finding consistent with edema.
Radiographics Restrepo 2011