ABSTRACT
BACKGROUND: Before performing endoscopy to remove prophylactic pancreatic stents placed in patients with high risk of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP), X-ray imaging is recommended to confirm the stents position in the pancreatic duct. OBJECTIVES: The aim of the present study was to investigate the feasibility of prophylactic pancreatic stent detection by transabdominal ultrasonography, to reduce the burden of X-ray imaging, which is currently the golden standard. METHODS: All patients who received a pancreatic stent for PEP prophylaxis were included in the present prospective trial. First, stent position was determined by transabdominal ultrasonography. Afterwards, it was verified by X-ray imaging. Retained stents were removed by esophagogastroduodenoscopy. Dislocated stents needed no further intervention. RESULTS: Fourty-one patients were enrolled in this study. All prophylactic pancreatic stents were straight 6 cm long 5 Fr stents with external flap. All stents were removed between day 1 and 10 (median: 3 days) in all cases. In 34 of 41 cases (83.0%), the pancreatic stent was still in place on the day of examination. Twenty-nine of 34 (85.3%) stents were detected correctly by transabdominal ultrasonography. Overlying gas prevented visualization of the pancreas in 3/41 (7.3%) cases. Sensitivity of sonographic detection of the stent was 93.5% (29/31). Six of seven stents were determined correctly as dislocated by ultrasonography. Here, specificity was 85.7%. A positive predictive value of 96.7% (29/30) was examined. The negative predictive value was 75.0% (6/8). CONCLUSION: Transabdominal ultrasonography detects the majority of prophylactic pancreatic stents. Thereby, it helps to identify patients with an indication for endoscopy sufficiently. X-ray imaging could subsequently be omitted in about 70% of examinations, reducing the radiation exposure for the patient and the endoscopy staff.
