['The aim of this study was to investigate whether perioperative morphologic characteristics are predictive of exocrine pancreatic function after pylorus-preserving pancreatoduodenectomy (PPPD) with pancreaticogastrostomy.', 'A 13C-labeled mixed triglyceride breath test was performed in 52 patients after PPPD to assess postoperative exocrine pancreatic function. A value of percent 13CO2 cumulative dose at 7 h (%CD-7 h) of less than 5% was considered diagnostic of exocrine pancreatic insufficiency. Pre- and postoperative pancreatic parenchymal thicknesses were calculated using computed tomography (CT) scans, and compared by means of receiver operating characteristic (ROC) analysis.', 'Thirty-four (65.4%) of 52 patients were found to have exocrine pancreatic insufficiency based on the breath test. With ROC analysis for identification of exocrine pancreatic insufficiency, the areas under the ROC curve for the postoperative pancreatic parenchymal thickness were higher than those for the preoperative pancreatic parenchymal thickness (0.904 and 0.702, respectively, P=0.009). When the cut-off value of the postoperative pancreatic parenchymal thickness was set at 13.0 mm, the sensitivity and specificity for identifying exocrine pancreatic insufficiency were 88.2% and 88.9%, respectively.'] Does reduced pancreatic parenchymal thickness indicate exocrine pancreatic insufficiency after pancreatoduodenectomy?