postcontrast enhancement
Increased signal intensity on MRI after gadolinium contrast administration, indicating blood-brain barrier breakdown.
Full Definition
Postcontrast enhancement refers to the increased signal intensity observed on T1-weighted MRI images after intravenous gadolinium contrast administration. In neurosurgical oncology, enhancement patterns provide crucial information about tumor characteristics, blood-brain barrier integrity, and disease activity. Enhancement typically indicates breakdown of the blood-brain barrier, which can result from tumor growth, inflammation, or treatment effects. Different enhancement patterns (rim, solid, heterogeneous) help characterize tumor types and distinguish between tumor recurrence and treatment effects such as radiation necrosis.
Usage
Usage note: Always specify timing relative to contrast administration; pattern description (rim, solid, heterogeneous) provides additional diagnostic information.
In Context
- "Postcontrast enhancement demonstrated a rim-enhancing lesion consistent with cystic tumor or abscess." — Radiology report
- "Follow-up imaging showed decreased postcontrast enhancement following treatment initiation." — Response assessment