Endoscopic Sphincter Balloon Dilation

Endoscopic Sphincter Balloon Dilation

In order not to destroy the bile, pancreas, ampullary sphincter and maintain the integrity of the papillary sphincter, EPBD (Endoscopic papillary balloon dilation) came into being. In 1983, Staritz first reported 11 cases of patients with choledocholithiasis who were successfully treated by EPBD, marking that EPBD, which can avoid the treatment of choledocholithiasis by nipple incision, was officially put into clinical use.

Advantages of EPBD

The advantages of EPBD lie in avoiding the incision of the duodenal papillary sphincter (Oddi) and destroying its physiological structure, so as to retain the normal function of the duodenal papillary sphincter to the greatest extent.

A prospective randomized study has been done to assess the Oddi sphincter in the EST group and EPBD group before the CBD stone retrieval operation, one week after the CBD stone retrieval operation and one year after CBD stone retrieval operation.

Before the CBD stone retrieval operation, the two groups which are included in the unified standard cases indicates that mean pressure of common bile duct is 4.6 (0.3) mmHg (0.61 Kpa), mean baseline pressure of sphincter is 9.0 (0.9) mmHg (1.20 Kpa), average peak pressure of sphincter is 111.0 (3.8) mmHg (14.80 Kpa), and average contraction frequency of sphincter is 8.5 (0.4) times/min.

The date comparison in EST group and EPBD group one week after CBD stone retrieval operation indicates that mean pressure of common bile duct is 0.2（0.1）mmHg（0.03 Kpa）VS 2.0（0.4）mmHg（0.27 Kpa）, the mean baseline pressure of sphincter is 0.6（0.3）mmHg（0.08 Kpa VS 3.3（0.5）mmHg（0.44 Kpa）, the average peak pressure of sphincter is 13.0（3.6）mmHg （1.73 Kpa）VS 58.3 （5.5）mmHg（7.77Kpa）, and the average contraction frequency of sphincter is 2.5times（0.7）VS 7 .4（0.5）times/min（P ＜ 0.05）. The date comparison in EST group and EPBD group one year after CBD stone retrieval operation indicates that mean pressure of common bile duct is 0.7（0.3）mmHg（0.09 Kpa）VS 2.1（0.5）mmHg（0.28 Kpa）, the mean baseline pressure of sphincter is 1.6（0.6）mmHg（0.21 Kpa）VS 4.2（0.6）mmHg（0.56 Kpa）, the average peak pressure of sphincter is 16.9（4.9）mmHg（2.25 Kpa）VS 74.6（6.1）mmHg（9.95 Kpa）, and the average contraction frequency of sphincter is 2.7（0.8）VS 7 .2（0.5）times/min（P ＜ 0.05）.

The incidence of choledocholithiasis was 40% VS 8.6% after one year (P < 0.05).

Although the Oddi function of EPBD group decreased one week and one year after operation,  compared with that before stone retrieval operations. That means the Oddi function could not be completely retained, but the retention degree was better than that of EST group, so the occurrence of long-term complications could be reduced. Another meta-analysis concluded that the rate of concurrent bleeding in the EPBD group was lower than that in the EST group (0.1%vs. 4.2%, P < 0.00001), so EPBD was suitable for patients with coagulation disorder.

For patients at risk of infection, EPBD significantly reduces short -term and long-term infections. For patients after gastrectomy operations, EST hemorrhage rate was 17%, compared with EPBD group of easier operation with almost no bleeding rate. Meanwhile, EPBD is safe and effective for patients with anatomic abnormalities or ampullary diverticulum.

Limitations of EPBD

In 1997, the results of an international multi-center trial showed that EPBD had a high incidence of postoperative pancreatitis, which reduced the enthusiasm of endoscopic experts at that time to use this operation for the treatment of choledocholithiasis. Age, ampullary diverticulum, dilatation pressure and dilatation time were all statistically significant risk factors for postoperative pancreatitis after EPBD, while pancreatic duct angiography was a significant risk factor. In addition, multivariate analyses showed that balloon dilation was the only factor highly associated with mortality. Because of the high-risk process of EPBD, it is prohibited as routine clinical practice in the UK, but in Europe,South Korea, Japan, the technology is still popular. Weinberg conducted meta-analysis and concluded that statistically, the success rate of stone extraction in EPBD was lower than that of EST, and the utilization rate of lithotripsy and the incidence of pancreatitis were higher. In addition, for patients with large number of stones (> 3) and long diameter (> 10mm), 15%~30% patients need to have ERCP after lithotripsy or ERCP.

Modern Digestion & Intervention 2013, Vol.18, No.5