Significance of early CT signs in acute stroke. A CT scan-diffusion MRI study

Cerebrovasc Dis. 2002;13(1):47-56. doi: 10.1159/000047746.


Objective: To study the pathophysiology of early CT signs.

Background: Early CT signs, due to an increase in tissue water content, are commonly attributed to cytotoxic edema and development of irreversible injury. This may have important implications for thrombolysis.

Methods: In patients with acute ischemic stroke in the middle cerebral artery territory, the areas of early CT signs and diffusion weighted imaging (DWI) hypersignal were independently assessed and drawn on a standardized atlas. Then, patients were classified into three groups (early CT signs larger than, similar to or smaller than DWI hypersignal) and compared with perfusion weighted imaging (PWI).

Results: Of 16 patients, CT scanning was performed with a median time of 3 h after onset and early CT scan signs were recorded in 10/16 patients (62.5%). DWI signal hyperintensity was present in 15/16 (94%) patients. In 7/16 (43%) patients, the area with early CT scan signs was larger than the DWI lesion ('CT-larger group'). Only in 2/16 (12%) patients were the areas matching ('matching group'). In 7/16 (43%) the DWI lesion was larger than the early CT scan signs area ('DWI-larger group'). When compared with PWI, the areas of early CT signs were larger than DWI hypersignal and were matching with PWI abnormalities (rMTT) in 2 cases, suggesting that they may represent a reversible process.

Conclusions: Early CT signs might have a potential dual fate: infarction or reversibility. Other techniques of recognizing reversible ischemic damage, such as DWI-PWI, are needed to improve acute stroke diagnosis and management.

Publication types

  • Comparative Study

MeSH terms

  • Acute Disease
  • Adult
  • Aged
  • Brain Ischemia / diagnostic imaging
  • Female
  • Humans
  • Infarction, Middle Cerebral Artery / diagnostic imaging*
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Tomography, X-Ray Computed*