Acute and chronic stroke: navigated spin-echo diffusion-weighted MR imaging

Radiology. 1996 May;199(2):403-8. doi: 10.1148/radiology.199.2.8668785.


Purpose: The authors evaluated a phase-navigated spin-echo (SE) motion-correction sequence for use at diffusion-weighted (DW) magnetic resonance (MR) imaging after cerebral infarction.

Materials and methods: Twenty-nine patients underwent 32 conventional T2-weighted fast SE and SE DW imaging after stroke (n=25), transient ischemic attack (n=3), or reversible ischemic neurologic deficit (n=1). Imaging was performed in a standard head holder with standard padding. Apparent diffusion coefficient (ADC) maps were constructed.

Results: DW images depicted high signal intensity compatible with localization of the ischemic symptoms in all cases. Lesions were depicted more clearly on DW than on T2-weighted images. On DW images, acute infarct ADC values were uniformly low (mean, 0.401x10(-5) cm2/sec =+/- 0.143 [standard deviation]) compared with control ADC values (mean, 0.754x10(-5) cm2/sec +/- 0.201). ADC values of chronic infarcts were supranormal (mean, 1.591x10(-5) cm2/sec +/- 0.840) compared with control values (mean, 0.788x10(-5) cm2/sec +/- 0.166). DW imaging did not show a change after transient ischemic attack. with reversible ischemic neurologic deficit, however, hyperintensity on DW images and low ADC resolved after symptoms abated.

Conclusion: Clinical phase-navigated SE DW imaging improved early diagnosis of stroke and helped differentiate acute from chronic stroke. Changes on DW images are reversed after symptoms resolve.

MeSH terms

  • Acute Disease
  • Aged
  • Brain / pathology*
  • Brain Ischemia / diagnosis*
  • Cerebral Infarction / diagnosis*
  • Cerebrovascular Circulation
  • Chronic Disease
  • Diagnosis, Differential
  • Female
  • Humans
  • Image Processing, Computer-Assisted
  • Ischemic Attack, Transient / diagnosis*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Time Factors