title: Ischemic findings of T2*-weighted 3-tesla MRI in acute stroke patients.
abstract: BACKGROUND
  We compared ischemic findings on gradient echo-type T(2)*-weighted images at 3-tesla MRI (T(2)*WI) in patients with acute ischemia and major vessel occlusion, and stroke patients with lacunar infarction or branch atheromatous disease.
  
  
  METHODS
  Our study population consisted of 45 patients with acute stroke. They underwent 3-tesla MRI within 12 h of stroke onset. Included were 24 patients (13 men and 11 women, mean age 68 years) with major vessel occlusion and 21 patients (11 men and 10 women, mean age 69 years) with minor infarction such as lacunar infarcts or branch atheromatous disease. We classified vascular ischemic findings of T(2)*WI into 3 sign categories, i.e. artery susceptibility sign, cortical vessel sign (hypointensity and enlargement of the cortical vessels) and brush sign (hypointensity of vessels in the deep white matter). Decreased intensity in the ischemic parenchyma was designated ischemic tissue sign. We compared regions of interest in the hypoperfused area on flow-sensitive alternating inversion recovery (FAIR) images with our vascular ischemic findings.
  
  
  RESULTS
  None of the vascular ischemic signs nor the ischemic tissue sign were found in patients with minor vessel disease. All 24 patients with major vessel occlusion manifested the cortical vessel sign, 23 the brush sign. The area with ischemic vessel signs on T(2)*WI was almost as large or somewhat smaller than the hypoperfused area on FAIR images. Compared to the contralateral side, 14 of 24 patients (58.3%) with major vessel occlusion showed decreased intensity in the ischemic parenchyma (ischemic tissue sign). Region of interest measurements on FAIR images demonstrated greater hypoperfusion in the area classified as ischemic tissue sign on T(2)*WI.
  
  
  CONCLUSIONS
  Ischemic vessel signs and the ischemic tissue sign on T(2)*WI at 3 T would be useful to evaluate the extensive ischemia due to major vessel occlusion and may be correlated with the blood-oxygen-level-dependent effect due to increased deoxyhemoglobin. The ischemic tissue sign may be reflective of severe ischemia.
authors: Department of Radiology, School of Medicine, University of Tokushima, Tokushima, Japan.
authors: Naomi
authors: N
authors: Morita
authors: Masafumi
authors: M
authors: Harada
authors: Masaaki
authors: M
authors: Uno
authors: Shunji
authors: S
authors: Matsubara
authors: Tsuyoshi
authors: T
authors: Matsuda
authors: Shinji
authors: S
authors: Nagahiro
authors: Hiromu
authors: H
authors: Nishitani
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020520:Brain Infarction / Q000473:pathology*; D002545:Brain Ischemia / Q000473:pathology*; D002533:Cerebral Angiography; D017352:Echo-Planar Imaging; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D020521:Stroke / Q000473:pathology*
chemical_list: D006454:Hemoglobins; C100003:deoxyhemoglobin