peritumoral edema
Brain tissue swelling surrounding a tumor, appearing as hyperintense signal on T2-weighted MRI sequences and indicating disrupted tissue integrity.
Full Definition
Peritumoral edema refers to the accumulation of fluid in brain tissue surrounding a tumor, resulting from disruption of the blood-brain barrier and increased vascular permeability. This edema appears as areas of increased signal intensity (hyperintensity) on T2-weighted and FLAIR MRI sequences, extending into the white matter beyond the tumor boundaries. The extent and pattern of peritumoral edema can provide diagnostic clues about tumor type and aggressiveness, with high-grade tumors typically producing more extensive edema. Management often requires corticosteroids to reduce intracranial pressure and associated neurological symptoms.
Usage
Usage note: Distinguish from tumor infiltration in clinical documentation; specify imaging sequence when describing findings.
In Context
- "Extensive peritumoral edema was noted in the right frontal white matter on FLAIR sequences." — MRI report
- "Dexamethasone was initiated to manage symptomatic peritumoral edema." — clinical note