Detectability of cerebral hemisphere ischaemic infarcts by CT within 6 h of stroke

Neuroradiology. 1996 Jan;38(1):31-3. doi: 10.1007/BF00593212.


To determine how early and how reliably ischaemic brain infarcts can be detected on CT within 6 h of the onset of cerebral hemisphere strokes, 44 such studies were interpreted by an experienced neuroradiologist blinded to clinical signs, but aware that the cohort was a stroke population. He was asked to detect and localise an area of parenchymal low density and/or focal brain swelling. A follow-up study showing the definite infarct served as a reference in each case. In 38 patients areas of slightly low density were seen, and in 36 follow-up CT confirmed infarcts in the locations indicated. In 2 patients the reading was false positive. In 6 patients no low density focus could be detected. In these 8 patients examined by CT within 180 min of the stroke, no low density could be identified, even in retrospect with the knowledge of the findings on follow-up. Thus, 42 readings (95%) were true positive or true negative; 2 were false positive; and none was a false negative. CT within 6 h of the onset of symptoms has a mean sensitivity of 82% (36/44) for ischaemic cerebral hemisphere infarcts. By contrast, its sensitivity to ischaemic parenchymal low density is low during the initial 2 h. The early development of hemispheric infarcts can be detected reliably if the radiologist is familiar with the signs.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Brain Edema / diagnostic imaging
  • Cerebral Infarction / diagnostic imaging*
  • Cohort Studies
  • Dominance, Cerebral / physiology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Sensitivity and Specificity
  • Tomography, X-Ray Computed*