Hypervasculaire

Hypervasculaire, or hypervascular, is an anatomical and radiological term used to describe tissue or lesions that have an increased density of blood vessels or higher blood flow than surrounding tissue. This condition can be physiological, reflecting normal vascularization in certain organs or stages of healing, or pathological, arising from processes such as tumor growth or inflammatory activity that promote angiogenesis and vascular remodeling.

In medical imaging, hypervascularity is a key characteristic that guides diagnosis and management. Hypervascular lesions typically show conspicuous, early enhancement after contrast administration on CT or MRI, often with rapid wash-in and variable wash-out in later phases. Doppler ultrasound may reveal increased blood flow and higher peak systolic velocities. Diagnostic angiography can quantify collateral supply and guide interventional procedures.

Common contexts in which hypervasculaire describes tissue include various tumors and inflammatory or infectious processes. Hypervascular tumors include hepatocellular carcinoma, certain thyroid malignancies, renal cell carcinoma metastases, and paragangliomas. Other benign or inflammatory conditions can also demonstrate increased vascularity, such as focal nodular hyperplasia of the liver or granulomatous inflammation.

Pathophysiologically, increased vascularity results from angiogenesis, driven by mediators such as vascular endothelial growth factor (VEGF) and other pro-angiogenic signals. The resulting microvascular network may be more tortuous and hemodynamically active, which can influence imaging appearance and clinical behavior.

Clinically, recognizing hypervasculaire tissue matters for biopsy planning, as higher bleeding risk may be present, and for treatment decisions, since anti-angiogenic therapies or preoperative embolization may be considered to reduce vascularity and hemorrhagic risk.