Structural Classification and Adaptive Symptoms of Choledochoscope

Ⅰ. The structure of the choledochoscope

A choledochoscope usually consists of an objective lens system, an optical imaging system, and an eyepiece system. It enters the body through natural orifices for imaging and diagnostics. The fiberoptic choledochoscope is mainly composed of a fiberoptic choledochoscope body and a cold light source. The lens body is connected to the light source by means of a connector to form a fully functional fiberoptic choledochoscopy and treatment system. In order to meet the needs of various inspections and treatments, it is usually equipped with a variety of accessories, mainly including stone extraction nets, biopsy forceps, cell brushes, irrigation catheters, cameras, and television video observation systems.

The body of the fiberoptic choledochoscope consists of two parts: hard and soft. The hard part includes an eyepiece and a direction control button, wherein the eyepiece can freely adjust the focal length, and the control button under the eyepiece can adjust the angle and direction of the flexible part at the front end of the soft part. The soft part is mainly a light guide system. The soft part is composed of 2 light source beam holes, 1 objective lens, and 1~2 lumen channels. It is wrapped with synthetic resin rubber and the front end is a flexible part.

Ⅱ. The structural classification of choledochoscopy

1. Rigid choledochoscopy: It can only be used for intraoperative choledochoscopy and treatment.

2. Flexible choledochoscopy (fibrous choledochoscopy): It can be used for intraoperative, postoperative and percutaneous transhepatic choledochoscopy and treatment.

3. Oral fiberoptic choledochoscopy: It can be used to directly enter the biliary tract through the mouth for examination and treatment after endoscopic sphincterotomy of the duodenal papilla (EST).

Ⅲ. Diagnosis and treatment of complications of choledochoscopy

The main complications of choledochoscopy include biliary tract infection, biliary tract hemorrhage, and sinus tract injury. Among them, infection is related to complicated intrahepatic bile duct stones, long operation time, high biliary pressure during operation, and poor postoperative T-tube drainage. Factors such as stone removal are related; sinus tract injury is related to factors such as poor sinus tract healing, blind endoscopy, violent stone removal, and blind catheter placement. It is recommended to choose the appropriate time of diagnosis and treatment, use preventive drugs, control the operation time, maintain a clear vision, pay attention to biliary pressure, avoid violence or blind operation, and close observation after flexible choledochoscope to reduce the occurrence or severity of complications.

Ⅳ. The timing of postoperative choledochoscopy diagnosis and treatment

It is recommended to perform choledochoscopy at least 6 weeks after laparotomy, and at least 8 weeks after laparoscopic surgery. For patients with advanced age (≥70 years old), malnutrition, severe diabetes, and long-term use of hormones, choledochoscopy should be performed at least 12 weeks after surgery. Patients with cirrhotic ascites, hypoalbuminemia and abnormal coagulation function should be corrected as much as possible and then undergo choledochoscopy as appropriate. Patients who are in urgent need of choledochoscopy can be advanced as appropriate after weighing the pros and cons.