Online Articles: Technical ReportsWhy Does Postoperative Pancreatic Fistula Occur After Hand-sewn Parenchymal Closure and Staple Closure in Distal Pancreatectomy?Nagakawa, Yuichi MD, PhD, FACS; Hijikata, Yosuke MD; Osakabe, Hiroaki MD; Matsudo, Takaaki MD; Soya, Ryoko MSc; Sahara, Yatsuka MD; Takishita, Chie MD; Shirota, Tomoki MD, PhD; Kobayashi, Nao MD; Nakajima, Tetsushi MD; Hosokawa, Yuichi MD; Ishizaki, Tetsuo MD, PhD, FACS; Katsumata, Kenji MD, PhD, FACS; Tsuchida, Akihiko MD, PhD, FACSAuthor Information Department of Gastrointestinal and Pediatric Surgery, Tokyo Medical University, Shinjuku-ku, Tokyo, Japan The author declares no conflicts of interest. Reprints: Yuichi Nagakawa, MD, PhD, FACS, Department of Gastrointestinal and Pediatric Surgery, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan (e-mail: email@example.com). Surgical Laparoscopy, Endoscopy & Percutaneous Techniques: April 2019 - Volume 29 - Issue 2 - p e15-e19 doi: 10.1097/SLE.0000000000000604 Buy Metrics Abstract Hand-sewing (HS) and stapling are common parenchymal closure techniques after distal pancreatectomy. However, these methods cannot completely prevent postoperative pancreatic fistula (POPF). The mechanisms of POPF formation after closure are unknown. We performed distal pancreatectomy in mongrel dogs to identify the mechanisms of POPF formation after HS and staple closure. We measured the closed pancreatic duct burst pressures and examined the histology of the remnant pancreas. The after staple-closure burst pressures depended on stapler height; lower pressures were associated with greater stapler heights. Post-HS closure burst pressures were significantly higher than those at each stapler height (P<0.01). Post-HS closure pathologic findings showed extensive necrosis (day 3), and some regenerated pancreatic duct stumps (day 5). Necrosis was not observed around the stapled tissues. Although HS completely closes the pancreatic ducts, stump necrosis and blood flow disturbances may cause POPF. With stapler closure, pancreatic fluid leakage may occur even with appropriate stapler heights. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.