Anatomical Challenges during Pancreaticoduodenectomy for Adenocarcinoma Head of Pancreas in Presence of Intestinal Rotation Abnormalities: A Report of Two Cases.

Pancreaticoduodenenctomy is a complex surgery and the sequence of steps is affected by anatomical variations involving small intestine and major vascular structures. This article depicts our approach to two such cases and highlights the importance of identifying these variations preoperatively on imaging, so as to modify the surgery plan accordingly.  We report following two cases of pancreatic head adenocarcinoma (1) one with incomplete intestinal rotation with a replaced right hepatic artery and (2) one with intestinal nonrotation. In both cases, the small bowel was aggregated on the right side of the abdomen, making duodenal mobilization challenging. The surgical approach was modified to prevent injury to these vessels. A superior mesenteric artery (SMA)-first approach helped in early isolation of vascular structures especially when vascular anomaly was also present. Interbowel adhesiolysis, limited kocherisation, tracing all vessels to its origin before division, paracolic anastomotic limb after a longer jejunal limb resection in nonrotation cases, and modification in retropancreatic tunnel creation are few of the key surgical adaptations.  Asymptomatic Intestinal malrotation is rare in adults and must be identified on preoperative imaging. Resultant intestinal and vascular anatomical variations need meticulous surgical planning and modification of conventional surgical approach for safe performance of PD.