gliosis
Pronunciation: gly-OH-sis
Proliferation and hypertrophy of glial cells in response to CNS injury, appearing as increased T2/FLAIR signal without mass effect.
Full Definition
Gliosis represents the brain's response to injury through astrocytic proliferation and hypertrophy, resulting in increased glial fibrillary acidic protein expression and tissue reorganization. On MRI, gliosis typically manifests as areas of increased T2 and FLAIR signal intensity without significant mass effect or enhancement. This finding is non-specific and may result from various etiologies including previous trauma, infection, ischemia, or inflammatory processes. Gliosis can be focal or diffuse and may evolve over time following the initial insult.
Usage
Usage note: Distinguish from active pathology; often requires clinical correlation for interpretation.
In Context
- "Chronic gliosis in the right temporal lobe was consistent with remote traumatic injury." — Follow-up MRI report
- "Areas of gliosis showed no interval change compared to prior imaging, supporting a stable post-infectious state." — Comparative imaging assessment