Hepatic hydrothorax in the absence of ascites diagnosed by intraperitoneal spraying of indocyanine green.

Hepatic hydrothorax in the absence of ascites is a rare complication of liver cirrhosis. A 56-year-old woman was referred to our hospital because of a massive pleural effusion on the right side, requiring continuous drainage. Although the patient was known to have chronic hepatitis C, she had no signs of hepatic failure including ascites. A laparoscopic examination revealed a nodular liver and a small volume of ascites in the peritoneal cavity. Indocyanine green sprayed into the intraperitoneal cavity was excreted from the pleural drain just after the spraying, indicating an intraperitoneal origin of the pleural fluid. Discontinuation of pleural drainage and an introduction of standard treatment for ascites due to liver cirrhosis (including restriction of salt intake and diuretic administration) resulted in a marked decrease of pleural effusion.