A chronic infarct refers to an area of tissue death (necrosis) resulting from a long-standing blockage of blood supply. It is characterized by specific features that distinguish it from more recent infarcts.
Characteristics of Chronic Infarcts
Chronic ischemic infarcts, specifically in the brain, display distinct characteristics on imaging. These include:
- Hypodensity: The affected area appears darker than surrounding tissue on CT scans due to tissue breakdown.
- Sharply Demarcated Margins: The edges of the infarct are well-defined, indicating a clear boundary between damaged and healthy tissue.
- Cystic CSF-filled Space: Over time, the damaged brain tissue is broken down and removed by phagocytosis, leaving behind a fluid-filled cavity containing cerebrospinal fluid (CSF). The parenchyma is replaced by this cystic space.
Example of Chronic Infarct
Consider a patient who experienced a stroke several months ago. A follow-up CT scan reveals a dark, well-defined area in the brain with the density of fluid. This is indicative of a chronic infarct where the damaged tissue has been replaced by CSF.
