Radioisotope scintigraphy in the diagnosis of hepatic hydrothorax

Background: Pleural effusion in cirrhotic patients (hepatic hydrothorax) ma y result from migration of ascitic fluid across defects in the diaphragm. B iochemical analysis of ascitic and pleural fluid provides only indirect inf ormation about the nature and origin of the effusion. The present study was performed in order to demonstrate the presence/absence of peritoneo-pleura l communication by radioisotope imaging. Methods: Ten patients with cirrhotic ascites and pleural effusion were stud ied with Tc-99m sulfur colloid scintigraphy to look for movement of the rad iotracer from the peritoneal to the pleural cavity. Serum-ascitic albumin g radient (SAAG) and serum-pleural fluid albumin gradient (SPAG) values were determined in eight patients to examine the nature of the ascitic and pleur al fluids. Results: Transdiaphragmatic movement of ascitic fluid into the pleural spac e was demonstrated (generally within 2 h of intraperitoneal injection of th e radiotracer) in eight of 10 patients; six on the right side, one on the l eft and one bilaterally. Two patients in whom pleural fluid was transudativ e on SPAG values were negative for peritoneo-pleural communications. Conclusions: Radionuclide scintigraphy is a simple, safe and relatively non -invasive method to confirm passage of ascitic fluid across the diaphragm. (C) 2001 Blackwell Science Asia Pty Ltd.