Acute cerebral infarction in monkeys: an experimental study using MR imaging.

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Acute cerebral infarction presents diagnostic challenges in early stages.
• Computed tomography (CT) may not reliably detect early ischemic changes.
• Magnetic resonance (MR) imaging offers potential for improved early infarct visualization.

Purpose of the Study:

• To define MR imaging features of acute cerebral infarction in a primate model.
• To correlate MR imaging findings with CT scans, laboratory analysis, and histopathology.
• To assess the utility of MR imaging in early stroke detection.

Main Methods:

• Experimental induction of acute cerebral infarction in five monkeys.
• Performance of serial MR imaging and CT scans.
• Postmortem histopathologic and spectrometric nuclear MR measurements of cerebral tissue.

Main Results:

• Acute infarcts (2-4 hours) were visible on MR imaging but not on initial CT scans.
• CT detected infarcts at 24 and 48 hours.
• MR imaging provided clearer depiction of infarcts as high signal intensity on T2-weighted images.
• Postmortem analysis confirmed prolonged T1 and T2 values and increased water content in infarct areas.

Conclusions:

• MR imaging is superior to CT for early detection of acute cerebral infarction.
• MR imaging findings correlate with histopathologic evidence of edema and tissue changes.
• T2-weighted MR sequences are sensitive for identifying early ischemic lesions.