Balloon-assisted enteroscopy has greatly improved the performance of ERCP in patients with SAA and has become the first-line treatment3,11–19. Undoubtedly, double-balloon enteroscopy (DBE) and SBE show the best performance. Spiral enteroscopy (SE) is also a good choice and reportedly has diagnostic and therapeutic yields similar to those of SBE-ERCP and SE-ERCP in patients with Roux-en-Y anatomy20. However, conventional SE systems are no longer commercially available21. Unfortunately, the working length of conventional DBE and SBE scopes is 200 cm, and the lack of ERCP accessories limits their clinical application. To circumvent this limitation, short-type DBE scopes and short SBE scopes have come into use7,18,22–25, with a working length of 155 and 152 cm, respectively. In one study, the total procedural success rate of short SBE-assisted ERCP ranged from 70.4–85.9%26. Short DBE showed a similar success rate23–25.
Identifying and intubating the afferent limb is the first and most critical step for successful endoscopic procedures. Skinner et al.21 reported that in most patients who have undergone Billroth II gastrojejunostomy, the afferent limb entrance is located on the right side. Tanisaka et al.26 stated that the steepest bend occurs in the afferent limb in patients who have undergone Billroth II gastrojejunostomy and pancreaticoduodenectomy. Tsutsumi et al.27 recommended advancing the short SBE scope to the middle loop in patients with Roux-en-Y reconstruction (side-to-side jejunojejunostomy), which can help to reach the papilla of Vater or pancreaticobiliary-enteric anastomosis. Mönkemüller et al.28 and Moreels et al.29 recommended using fluoroscopy control to aid in the localization of the jejunojejunal anastomosis. They also recommended using fluoroscopy to identify the movement of the short SBE scope toward the liver shadow, indicating successful intubation of the afferent limb. Several methods are available for identifying the afferent limb, such as finding a disruption of the transverse folds or using intraluminal indigo carmine injection or carbon dioxide insufflation at the Roux-en-Y anastomosis26,28,29.
The “push and pull” method for safe and smooth advancement of the short SBE scope along the intestinal wall has been discussed in detail9,21,26, as has the maneuver for use of an overtube21,26. In some difficult cases, the patient’s position must be changed or abdominal pressure must be applied8,21. Occasionally, the surgeon must wait for favorable intestinal peristalsis before intubation can be performed, when the operating part of the short SBE scope is almost fully pressed against the patient’s mouth. The “wait and go ahead” principle should be adopted. In our center, we also use the method of dragging the retrieval balloon back to drive the enteroscope forward.
The SIF-H290S used in the present study is a relatively new type of short SBE scope that was introduced in Japan in 20167. Despite our patience, perseverance, and use of all aforementioned techniques, the enteroscopy success rate is lower (only 57.6%) and the intubation time is longer in the present study than in previous studies7,18,21,26. There are several possible reasons for this. First, most of the patients in this study had malignancies (41.4% of procedures). Second, the heterogeneity of surgical quality may have led to an excessive length or angle of the afferent loop. Third, the proportion of patients undergoing endoscopic procedures after Roux-en-Y reconstruction was 47.5%. Previous research has demonstrated that Roux-en-Y anastomosis and malignancies are the main risk factors for procedural failure30. In addition, a transparent hood has been found to be useful for enteroscope insertion to the afferent limb31. However, the present study did not yield such results. During endoscopic intubation in some cases, we found that the majority of the body of the short SBE scope was coiled within the stomach cavity. Therefore, we believe that gastrectomy is beneficial for intubation. In addition, compared to previous studies, our study did not yield such positive outcomes. Moreover, we found that Roux-en-Y reconstruction was the only independent factor related to intubation failure in this study.
Adverse events may occur when inserting the enteroscope to the target site, including intestinal bleeding and perforation, particularly in patients with tight adhesions8. In one study, intestinal perforation occurred in 1.9% of patients30. In the present study, only one patient with choledocholithiasis after Billroth II anastomosis due to gastric cancer developed mild postoperative pancreatitis. No major adverse events occurred, such as significant post-ERCP bleeding or perforation. In fact, our experience has shown that removing plastic stents through the enteroscopy site is much more difficult than inserting plastic stents. The nasobiliary duct can be used as a substitute. Simultaneously or subsequently incising the nasobiliary duct and retaining it within the stomach is beneficial for stent removal.
Percutaneous transhepatic biliary drainage is a remedial method for failed short SBE-assisted ERCP8. Short SBE-assisted ERCP using the rendezvous technique may be helpful for patients with a sharply angulated Roux-en-Y limb21,32. A motorized spiral enteroscope (PSF-1; Olympus Medical Systems) with a working length of 168 cm and a working channel diameter of 3.2 mm has been available since 2015. Motorized SE-assisted ERCP in patients with SAA reportedly facilitates successful and rapid enteroscopic access and cannulation8,33. Alternative treatment modalities have also been recently developed, including laparoscopy-assisted ERCP and interventional endoscopic ultrasound (EUS)8. Laparoscopy-assisted ERCP reportedly achieved high success rates in some patients with a history of Roux-en-Y gastric bypass surgery34. Interventional EUS also provides a higher success rate and shorter procedure time than balloon enteroscopy-assisted ERCP in some patients with SAA8,35. Moreover, endoscopic ultrasound-directed transgastric ERCP, a recently emerging technique, may be superior to laparoscopy-assisted ERCP because of its shorter procedure time and length of hospital stay36.
In conclusion, short SBE is a safe first-line method for managing pancreatobiliary disease in patients with SAA. Difficult cases, particularly those involving patients with a history of Roux-en-Y reconstruction, require the combination of other methods or the search for alternative solutions.