The head of the pancreas is exposed, dividing the gastrocolic and duodenocolic ligaments, preserving the gastroepiploic vessels. Subsequently, the duodenum is mobilized by a Kocher maneuver. After identification of the superior mesenteric vein at the lower margin of the pancreatic head, preparation of a tunnel between the portal vein and the pancreatic neck has to be performed.

Even in cases of extensive inflammation, the tunneling can be performed without major difficulties. The identification and looping of the common hepatic artery is carried out on the upper margin of the neck and head of the pancreas. The common bile duct is identified and banded with a rubber loop in the hepatoduodenal ligament (Fig. 1).

Resection of the inflammatory mass in the pancreatic head is initiated with a transverse division of the pancreatic neck at the duodenal edge of the portal vein (Fig. 1). At the cut surface of the left pancreas, meticulous hemostasis using monofilament 5-0 to 6-0 nonabsorbable sutures is carried out. The head of the pancreas is rotated forward and to the right (Fig. 2). This can be achieved easily by bluntly freeing the head of pancreas from the portal vein; small branches entering the portal vein and superior mesenteric vein are ligated. The head of the pancreas is removed, using a knife, from the retroperitoneal surface of the pancreas toward the uncinate process without major technical difficulties (Fig. 3A). The subtotal resection of the pancreatic head is completed by including the tissue of the uncinate process and excising the pancreatic head tissue at a distance of 5 mm from the duodenal wall. The wet weight of the operative specimen after subtotal pancreatic head resection lies between 25 and 50 g. It has not proved necessary to preserve the gastroduodenal artery for ensuring an optimal blood supply to the duodenal wall because the supraduodenal vessels, the dorsal pancreaticoduodenal arcades, and the mesoduodenal vessels maintain the blood supply. The dissection of the intrapancreatic segment of the common bile duct is started at the upper margin of the pancreatic head (Fig. 3B). In most cases, decompression of the common bile duct can be achieved by dissecting the pancreatic tissue along the common bile duct wall. The dorsal capsula of the pancreatic head is preserved.

In cases with an inflammatory process in the wall of the common bile duct causing duct narrowing, the duct is opened by excising a 15 × 5 mm wall segment (Fig. 4). After completion of the subtotal resection of the pancreatic head, a shell-like, 5 to 8 mm wide remnant of the tissue of the pancreatic head is left connected to the duodenal wall (Fig. 5). Meticulous suturing of any bleeding vessels using 5-0 to 6-0 nonabsorbable suture material is recommended.

Reconstruction is executed by dissecting the most proximal jejunal loop 20 cm distally to the ligament of Treitz. The aboral jejunal loop is transposed via a retrocolic mesenteric opening to the pancreatic head, and an end-to-end anastomosis using a two-layered technique is fashioned between the pancreatic neck and the jejunal loop (Fig. 6). In patients with a dilated main pancreatic duct and multiple fibrotic duct stenoses, the main pancreatic duct is incised longitudinally at its anterior surface up to the tail of the pancreas. In these patients, the anastomosis is performed as a side-to-side anastomosis, as a Partington–Rochelle modification of drainage of the main pancreatic duct (Fig. 7). A single- or double-layer suture between the jejunum and the residual head of the pancreas along the excision line has to be carried out at a distance of 5 to 8 cm from the anastomosis with the left pancreas.

An additional anastomosis between the common bile duct and the jejunal loop is not mandatory. The opening of the common bile duct is included in the pancreatic anastomosis, which is carried out with the remnant of the pancreatic head (Figs. 7 and 8).

For restoration of the food transit, a typical Roux-en-Y anastomosis is sutured 20 cm distal to the pancreaticojejunal anastomosis (Fig. 8).

In patients with severe stenosis of the duodenum, dissection of the tissue at the ventral surface of the duodenum, causing
encasement of the duodenum, has to be carried out. The stenosis is caused by fibrous tissue bands at the ventral wall of the suprapapillary duodenum. Removal of the fibrous layers up to the level of the serosa results in restoration of a normal diameter of the duodenum. The subtotal resection of the pancreatic head brings about in decompression of the portal vein and an immediate release of the signs of portal hypertension.

Clinical observations and immunologic and molecular biologic data underline the hypothesis that the pancreatic head is the pacemaker of chronic pancreatitis. The subtotal duodenum-preserving resection of the pancreatic head results in relief of local complications. The coring-out technique of Frey is a modification of the Partington–Rochelle duct drainage procedure resulting in duct decompression, but it conserves the inflammatory tissue mass of the pancreatic head if only 6 g of pancreatic head tissue is excised. In comparison to Whipple resection and pylorus-preserving pancreaticoduodenectomy, the subtotal duodenum-preserving pancreatic head resection offers the major advantage of preserving the extrahepatic biliary tree, stomach, and duodenum. In five randomized controlled clinical trials, the superiority of the duodenum-preserving technique compared to Whipple resection or pylorus-preserving resection has been demonstrated for the patients suffering from advanced chronic pancreatitis. In terms of hospital death rates, frequency of relaparotomy, and complications as well, the subtotal pancreatic head resection offers the major advantage of low postoperative morbidity (Table 3).