What is the term for the characteristic abdominal wall vein pattern seen in portal hypertension radiating outward from the umbilicus?

Explanation

## Caput Medusae: Portal Hypertension Sign ### Definition and Mechanism **Caput medusae** (Latin: "head of Medusa") refers to the dilated, tortuous abdominal wall veins that radiate outward from the umbilicus in a pattern resembling the hair of the mythological Medusa. This occurs due to reversal of blood flow in the umbilical vein secondary to portal hypertension. ### Pathophysiology 1. Portal hypertension increases intrahepatic resistance 2. Blood seeks alternative routes via portosystemic collaterals 3. The umbilical vein (normally obliterated) reopens as a collateral 4. Venous blood flows from portal system → umbilical vein → superficial epigastric veins → radiate outward 5. Creates characteristic "medusa-like" radiating pattern around umbilicus ### Clinical Significance **Key Point:** Caput medusae is a sign of **chronic portal hypertension** and indicates decompensated liver disease with portosystemic shunting. **High-Yield:** The direction of blood flow in caput medusae is **cephalad and caudad from the umbilicus** (away from center), which distinguishes it from normal venous flow. ### Associated Signs of Portal Hypertension | Sign | Location | Mechanism | Significance | |------|----------|-----------|---------------| | **Caput medusae** | Abdominal wall, radiating from umbilicus | Reopened umbilical vein + portosystemic collaterals | Chronic portal hypertension | | **Ascites** | Peritoneal cavity | Portal hypertension + hypoalbuminemia | Decompensated cirrhosis | | **Splenomegaly** | Left upper quadrant | Splenic venous congestion | Portal hypertension | | **Hemorrhoids** | Rectum | Superior rectal vein dilation | Portosystemic collateral | | **Esophageal varices** | Esophagus | Coronary vein dilation | High-risk bleeding source | **Clinical Pearl:** Caput medusae is less common than ascites or splenomegaly in portal hypertension, but when present, it is highly specific for portal hypertension and indicates advanced liver disease. **Mnemonic:** **MEDUSA = Veins radiating from umbilicus** — Remember the mythological Medusa with snakes radiating from her head, just as veins radiate from the umbilicus.