contrast enhancement
Increased signal intensity on post-contrast imaging indicating blood-brain barrier disruption or increased vascularity in tumor tissue.
Full Definition
Contrast enhancement refers to the increased signal intensity observed on MRI or CT imaging following intravenous administration of contrast agents, typically gadolinium for MRI or iodinated compounds for CT. In neurosurgical oncology, contrast enhancement indicates areas where the blood-brain barrier has been disrupted, allowing contrast material to accumulate in tissue. This phenomenon is characteristic of many malignant brain tumors, which often demonstrate avid enhancement due to their abnormal vasculature and breakdown of normal blood-brain barrier integrity. The pattern, degree, and characteristics of enhancement provide important diagnostic and prognostic information. However, enhancement patterns can be complex, as some malignant tumors may not enhance while some benign conditions do enhance.
Usage
Usage note: Can be described as avid, mild, heterogeneous, or absent; pattern description important.
In Context
- "The lesion showed avid contrast enhancement suggesting high-grade malignancy." — radiology interpretation
- "Lack of contrast enhancement does not exclude infiltrative tumor growth." — imaging review