Congenital common bile duct dilation is the most common hepatobiliary surgical disease in pediatric patients, most of whom are female, with a male-to-female ratio of 1:3. The cause of the disease is unclear and may be related to genetic mutations, but most recent scholars believe that it is due to abnormal biliopancreatic cohesion. The clinical typing is most common with type I, accounting for about 90% of all CCCs. Due to the development of modern imaging, clinical diagnosis is relatively easy. Treatment is mainly surgical resection, and clinical complications are more common, mainly including surgical and non-surgical complications.
I. Non-surgical complications
1.Biliary cirrhosis
The main causes of biliary cirrhosis are biliary tract infection and biliary tract obstruction. Domestic research by Yu Shiyao et al. found that cirrhosis is not only related to biliary tract infection and obstruction, but also related to the size and age of the cyst, and the younger the age, the larger the cyst the higher the degree and chance of cirrhosis. Clinically, pediatric patients with recurrent jaundice and fever should pay high attention to this disease and need timely surgical treatment to relieve biliary tract infection and obstruction.
2. Pancreatitis
Abnormal biliopancreatic syncope is the pathological basis of CCC combined with pancreatitis. The pancreaticobiliary ducts converge outside the duodenal wall and lose their respective sphincter function. Trypsin is activated by the refluxed bile, while trypsin activates other enzymes, among which phospholipase destroys the lipoprotein structure of the vessel wall and pancreatic duct, pancreatic cell membrane and mitochondrial membrane, causing a series of pancreatic inflammatory reactions. The flow of bile into the pancreatic duct disrupts the epithelial barrier of the pancreatic duct, leading to the development of pancreatic inflammation.
Adult patients with combined gallbladder and bile duct sediment-like stones are also susceptible to complications of pancreatitis as an important cause, and Sugiyama et al. reported a 31% incidence of acute pancreatitis in patients with abnormal biliopancreatic commiseration. The treatment can improve the clinical symptoms of pancreatitis by ENBD + medical treatment, and it is generally not recommended to perform cyst excision during the attack of pancreatitis, because it is difficult to remove the cyst in the pancreatic segment of the common bile duct during the attack of pancreatitis, and forcible peeling of the cyst may cause hemorrhage due to portal vein tearing.
3.Biliary tract infection and stone
Biliary tract infection and stones are the most common complications of CCC, the incidence of which is 62.1% in adults and 13% in pediatric patients, with extrahepatic biliary tract predominant, mainly bile pigment stones. Stone formation is mainly due to pancreatic fluid reflux and activation of pancreatic lipase, which degrades glycerol triphosphate into glycerol and stearic acid, which combines with calcium to form calcium stearate stones.
Glycerol is further oxidized to citric acid, which combines with calcium to form citrate stones. Stenosis of the bile duct ends and bile stasis are also associated with a higher chance of common bile duct stone formation and biliary tract infection. Treatment can be combined with combined resection of common bile duct cyst, if the infection is more serious, the obstruction can be temporarily released by ENBD and elective surgery.
4.Carcinoma
Kimura reported 65 cases of CCC patients, 16 of which were combined with gallbladder cancer. The main reasons for their occurrence are absolute or relative stenosis of the distal bile duct outlet and pancreatic fluid reflux, resulting in mucosal damage as the pathological basis of carcinoma. The increased concentration of secondary bile acids and free bile acids in bile has potential carcinogenic effects. Also some scholars found that genetic mutation is also an important cause of carcinogenesis. Only by removing the cyst can the pathological changes be terminated.
5.Spontaneous perforation
Spontaneous perforation of congenital common bile duct cyst is a rare complication with an incidence of 1.8-7.0%, mainly due to abnormal pancreaticobiliary duct cohesion, which makes the pancreatic fluid reflux causing weakness of the cyst wall. For treatment, if the abdominal infection is light, cyst excision and bile-intestinal anastomosis can be taken, if the infection is heavy, only external drainage is suitable.
Two surgical complications
1.Intraoperative bleeding
In CCC with repeated co-infection, the cyst wall forms more collateral circulation and adhesions with portal vein. It is very easy to damage the portal vein when separating and removing the cyst, and even cause partial avulsion of the portal vein leading to hemorrhage. For such cases, the internal capsule can be resected and the external capsule can be preserved. The damage to the surrounding tissues can be avoided.
2.Postoperative bile leak
Postoperative bile leak may be caused by inaccurate anastomosis due to narrow proximal bile duct opening after complete removal of the cyst, and too many sutures during anastomosis, resulting in bile leak. The way to avoid it is to try to ensure that the anastomosis is large enough and apply absorbable threads for exact suturing.
3.Anastomotic stenosis
Anastomotic stenosis is one of the most common long term complications after CCC surgery. The reason is mainly that firstly the anastomosis itself is small, and after surgery scarring occurs and the anastomosis is narrowed. Secondly, the bile duct is stripped too cleanly during surgery, which damages the biliary trophoblastic vessels and results in postoperative scarring and anastomotic stenosis. Third, non-absorbable sutures are used during surgery, and stones form around the anastomosis around the line node after surgery, leading to anastomotic obstruction.
For prevention and treatment, the method introduced by Lilly strips the mucosa of the posterior wall of the cyst cleanly, while allowing the residual outer fibrous tissue, leaving a flared opening in the upper part of the common bile duct for anastomosis with the jejunum. A small skirt was left at the upper end of the resected cyst to peel away the inner wall of the cyst, ensuring that the anastomosis reached a width of 2 cm and applying an absorbable wire anastomosis with continuous posterior wall and interrupted anterior wall. The trophoblastic vessels of the preserved biliary tract are also protected.
4.Carcinoma of the common bile duct
In the early stage of CCC surgery, surgeons were not aware of this disease, and most of them did not resect and performed cystic jejunostomy or duodenal anastomosis, and the postoperative carcinoma rate was much higher than that of non-operative cases. Todani et al. reported that among 63 cases of congenital common bile duct cysts with carcinoma, 36 cases had internal drainage of cysts, and the internal drainage caused the activation of pancreatic fluid when the intestinal fluid of enterokinase returned to the cysts, and the long-term chronic stimulation caused The long-term chronic stimulation causes cancer.
In China, Liu Yingbin et al. reported 20 cases of choledochal cyst carcinoma, including 11 cases of carcinoma after internal drainage, and the emergence of resection Roux-Y choledochal jejunostomy can largely avoid the occurrence of postoperative carcinoma, but due to the immaturity of the surgical technique of some physicians in the basic hospital, the surgical resection of the lower part of the cyst was not enough, and carcinoma occurred after surgery.
5.Postoperative cholangitis and stone formation
Postoperative cholangitis and bile duct stones are relatively common, mainly due to anastomotic stenosis and postoperative intestinal fluid reflux, causing biliary tract infection and stone formation. Its avoidance method try to ensure that the anastomosis is large enough, take the common bile duct jejunum Roux-Y anastomosis, the jejunal loop should not be too long or too short, and some anti-reflux devices can be designed.