• contrast-enhanced ultrasonography;
  • hepatic hydrothorax;
  • liver cirrhosis;
  • Sonazoid


Background and Aim:  We investigated the utility and safety of contrast-enhanced ultrasonography using Sonazoid in the diagnosis of hepatic hydrothorax.

Methods:  The study consisted of seven liver cirrhosis patients with hydrothorax and hydroperitoneum. After obtaining informed consent, Sonazoid was injected intraperitoneally, and enhancement in the peritoneal and pleural cavities was observed.

Results:  In all patients, the peritoneal cavity was quickly enhanced after the Sonazoid injection. The pleural cavity was enhanced in five of the seven patients, and these five patients were diagnosed with hepatic hydrothorax. Two patients without enhancement of the pleural cavity were diagnosed with inflammatory hydrothorax.

Conclusions:  This is the first report to confirm transdiaphragmatic movement of ascitic fluid into the pleural cavity using contrast-enhanced ultrasonography with Sonazoid. This method can safely detect ascitic flow in real time, and is thus very useful for the diagnosis of hepatic hydrothorax.