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Regional cerebral hyperperfusion associated with postictal paresis
Journal of Vascular and Interventional Neurology
|June 28, 2012
Summary
Postictal paresis, a symptom following seizures, may involve increased brain activity. CT perfusion scans revealed hyperperfusion in patients experiencing Todd
Area of Science:
- Neurology
- Neuroimaging
- Epileptology
Background:
- The exact mechanisms behind postictal paresis and Todd's phenomenon remain unclear.
- Existing theories propose neuronal exhaustion, desensitization, or active suppression as potential causes.
Purpose of the Study:
- To investigate the cerebral perfusion patterns associated with postictal paresis.
- To explore the potential role of active physiological processes in Todd's phenomenon.
Main Methods:
- A case series approach was used.
- CT perfusion imaging was performed on two patients presenting with postictal paresis.
- Cerebral blood flow, volume, and mean transit time were analyzed.
Main Results:
- CT perfusion revealed hyperperfusion in the affected intracranial regions.
- Specific findings included increased cerebral blood flow and volume.
- A decrease in mean transit time was also observed, correlating with neurological symptoms.
Conclusions:
- The observed hyperperfusion suggests an active physiological process during Todd's phenomenon.
- Adequate cerebral perfusion may be crucial for the resolution of postictal symptoms.
- These findings challenge purely exhaustive models and support active mechanisms.
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