Sonographic findings of portal hypertension
- Portal hypertension can be suggested when (1) PV diameter is larger than 13 mm, (2) there is less than 20% increase in the PV diameter with deep inspiration, (3) a monophasic waveform is present, and (4) flow velocity is decreased.
- Specific measurements may be unreliable given PV diameter variability and the formation of portosystemic collaterals, which often develop in response to portal hypertension, reducing the PV diameter.
- Common collaterals include (1) a recanalized paraumbilical vein, which runs in the falciform ligament to the abdominal wall and drains the left PV; (2) splenorenal shunts; (3) retroperitoneal veins; (4) hemorrhoidal veins; and (5) the coronary vein, which connects with the portosplenic confluence and ascends to the gastroesophageal junction, producing esophageal varices.
- A coronary vein diameter larger than 7 mm is highly associated with severe portal hypertension.
- Retrograde (hepatofugal) PV flow indicates advanced disease and is a useful but late finding
