Intracavitary Contrast-Enhanced Ultrasound in the Management of Post-Surgical Gastrointestinal Fistulas.

The goal of this study was to investigate intracavitary contrast-enhanced ultrasound (IC-CEUS) measures in the management of post-surgical gastrointestinal (GI) fistula throughout detection, treatment and follow-up. From June 2010 to August 2016, patients who were administered ultrasound contrast agent (UCA) via a drainage tube for IC-CEUS were enrolled and retrospectively analyzed. They were suspected of having GI anastomotic fistulas or had been found to have fluid collections with ultrasound that were accompanied by abdominal pain or fever after surgical procedures. Forty-two patients met the inclusion criteria and were enrolled into this study. Twenty-two were confirmed to have GI fistulas confirmed by standard references. None were detected by conventional ultrasound. Although IC-CEUS successfully detected GI fistulas in 16 patients, it missed GI fistulas in 6 patients. One patient was misdiagnosed with a GI fistula. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the diagnosis of GI fistulas by IC-CEUS were 72.7% (16/22), 95.0% (19/20), 94.1% (16/17), 76.0% (19/25) and 83.3% (35/42), respectively. Twenty peritoneal fluid collections in 14 patients were related to fistulas by IC-CEUS based on the distribution of ultrasound contrast agents. Additional drainage was performed in 14 fistula-related fluid collections. Eight GI fistulas were judged to be cured after IC-CEUS re-evaluation, and the drainage tubes were removed from these patients. In conclusion, IC-CEUS can greatly improve the ability to diagnose post-surgical GI fistulas and may also play an important role in interventional treatment and follow-up.