Leukocyte infiltration in acute hemispheric ischemic stroke

Area of Science:

• Neurology
• Nuclear Medicine
• Immunology

Background:

• Cerebral ischemia, particularly hemispheric ischemic stroke, involves complex inflammatory processes.
• Understanding leukocyte dynamics is crucial for managing stroke outcomes.

Purpose of the Study:

• To investigate the temporal dynamics of leukocyte infiltration in human cerebral ischemia.
• To evaluate the utility of technetium-99m hexamethylpropyleneamine oxime (99mTc HMPAO)-labeled leukocyte brain single-photon emission computed tomography (SPECT) for this purpose.

Main Methods:

• Twenty-two patients with hemispheric ischemic stroke (19 acute, 3 chronic) underwent 99mTc HMPAO brain SPECT for perfusion and leukocyte infiltration assessment.
• Follow-up SPECT scans were performed at 1-3 week intervals for acute stroke patients.

Main Results:

• In chronic stroke, no leukocyte infiltration was observed in perfusion defect areas.
• In acute stroke, leukocyte infiltration was detected in perfusion defects during the acute phase.
• This infiltration persisted for a minimum of 5 weeks post-onset before showing a decline.

Conclusions:

• A novel method utilizing 99mTc HMPAO-labeled leukocyte brain SPECT enables the study and monitoring of leukocyte infiltration in acute cerebral ischemia.
• Leukocyte infiltration in acute hemispheric ischemic stroke is a dynamic process with a prolonged duration of at least 5 weeks.