The initial treatment for CP is often medical therapy, but for the patient refractory to medical therapy, endoscopic or surgical therapy is an alternative. One recent meta-analysis compared endoscopic and surgical interventions in patients with CP and concluded that surgery is a promising approach in the treatment of CP, with the obvious advantage of pain relief, which is difficult to achieve with medical treatment [7]. One study reported that earlier surgical drainage of the obstructed pancreatic duct led to better recovery of histologic changes and pancreatic exocrine dysfunction compared with late surgical drainage in an experimental model of obstructive pancreatitis [8].
A case of CP which has severe stenosis of the pancreatic duct is necessary not only for the Frey procedure, but also pancreatectomies (Figs.1-4). One study reported that Frey with DP can be a promising treatment for CP patients with pancreatic head and tail lesions[6]. We selected the hybrid approach in these cases. Minimal invasiveness is a very important point for the treatment of CP, which is a benign disease, even though the case is refractory to medical therapy. Benign pancreatic disease is a good indication for laparoscopic surgery[9]. There is one study which reported that laparoscopic distal pancreatectomy was associated with favorable perioperative outcomes compared with open distal pancreatectomy[10]. We selected a laparoscopic approach before performing the Frey procedure, attaching great importance to the minimal invasiveness. The new point of this procedure is hybrid approach. An incomplete Frey procedure must be avoided. It is essential that the Frey procedure (coring out of the pancreas and removal of the pancreatic calculus) be completed for treatment of CP. We do not perform these procedures laparoscopically for safety reasons and to ensure completion of the procedure. Our hybrid procedure is the best approach from the viewpoint of safety and minimal invasiveness. We think that the procedure based on these concepts contains novelty.
The key points of our hybrid procedures are selecting two approaches for the appropriate situation. We selected the laparoscopic approach for situations which can be performed safely from the viewpoint of minimal invasiveness and selected an open approach for the situations which are high risk from the viewpoint of safety. For example, the former situation is the distal pancreatectomy and the latter situation is the coring out of the head of the pancreas. Our institute performed the hybrid approach for CP, which is necessary for resection of the pancreas with the Frey procedure. We have not experienced open approach for these cases, so we compared this new method with the open approach for only Frey and only DP. These results indicated that the perioperative results of our new method were relatively good (Table 1). In our hospital, we basically use a clinical path for pancreatic surgery, and if no complications is found, the diet will start on the 5th day after surgery, and the patient will be discharged in about two weeks in the case of DP. Since reported cases also used this clinical path, the mean postoperative hospital stay was 16days.

An incomplete Frey procedure is associated with a risk of CP recurrence. Sometimes operation time became long because of the severe inflammation and the needs of a reliable coring out of the head of pancreas under such situations. To perform a complete Frey procedure safely, hand assistance is very useful to prevent injury to the splenic vein. We placed our hand posterior to the head of the pancreas to confirm the depth of coring out and the distance to the splenic vein. We are of the opinion that mini-laparotomy does not add a large incision because a 5-cm wound is needed for extraction of the distal pancreas in any case. We performed the Frey procedure completely to raise the success rate in achieving long-term pain relief.