ischemia
Pronunciation: is-KEE-mee-ah
Inadequate blood supply to brain tissue, potentially leading to neuronal death and stroke.
Full Definition
Cerebral ischemia occurs when blood flow to brain tissue is reduced below the threshold necessary to maintain normal neuronal function and viability. It can be focal (affecting a specific brain region) or global (affecting the entire brain). Ischemia may be temporary (transient ischemic attack) or prolonged, leading to irreversible tissue damage (infarction). The condition triggers a complex cascade of cellular events including energy depletion, ionic imbalance, and inflammatory responses. Rapid recognition and treatment are crucial for optimal outcomes.
Usage
Usage note: Distinguish from infarction, which implies irreversible tissue death.
In Context
- "Diffusion-weighted MRI showed acute ischemia in the left middle cerebral artery territory." — Emergency radiology report
- "The patient experienced transient cerebral ischemia with complete symptom resolution." — Stroke clinic follow-up note