hypodensity
Pronunciation: hahy-poh-DEN-si-tee
An area that appears darker than surrounding tissue on CT imaging due to lower X-ray attenuation.
Full Definition
Hypodensity describes regions on CT scans that demonstrate lower attenuation values compared to adjacent normal tissue, appearing darker on standard viewing windows. In oncologic radiology, hypodensity can indicate various pathologic processes including tumor necrosis, cystic change, fat content, or fluid accumulation. Liver metastases commonly appear hypodense on pre-contrast images, while brain tumors may show hypodense areas representing edema or necrosis. Quantitative assessment using Hounsfield units provides objective measurement of tissue density, helping characterize lesion composition and guide differential diagnosis. The degree and pattern of hypodensity, along with enhancement characteristics, are crucial for accurate interpretation.
Usage
Usage note: CT-specific term; use hypointensity for MRI findings; include Hounsfield units when available.
In Context
- "Multiple hypodense lesions throughout the liver were consistent with metastatic disease." — Abdominal CT report
- "The tumor demonstrated central hypodensity suggesting necrotic change." — Oncologic imaging interpretation