A new cannula with a flexible tip (Swing Tip) may improve the success rate of endoscopic retrograde cholangiopancreatography

Steerable catheter based on wire-driven seamless artificial blood vessel tube for endoscopic retrograde transpapillary interventions

PURPOSE

Current steerable catheters (SCs) for endoscopic retrograde cholangiopancreatography (ERCP) have performance limitations caused by an asymmetric multiple-slit tube design with a small maximum bend angle, lesser curvatures, and insufficient durability. We propose a wire-driven SC for balanced bidirectional bending using artificial blood vessel material to overcome these limitations. We assess the SC prototype's steerability using phantom and animal models.

METHODS

The SC prototype employed a slit-less and multiple-lumen seamless tube with a polytetrafluoroethylene (PTFE) body with stretch-retractable porous expanded PTFE at the distal end, and loop-formed control wires. We evaluated the wire routing design using a static model. The bending performance was compared with conventional SCs. Feasibility studies were performed, including major duodenal papilla insertions and ductal branch selections in desktop phantoms and a mini-pig model.

RESULTS

The proposed design reduced the wire contact force by 48% compared to the single wire configuration. The maximum bend angle was 162°, almost twofold larger than that for conventional SCs. The lateral tip position in the bent shape was maximally 56% smaller. The tip flexibility was comparable to conventional SCs, and the insertion resistance was similar to the passive catheters. Phantom studies showed that the SC prototype could perform the large and protuberant papilla insertions and fine ductal branch selections without breaking; the animal study was completed successfully.

CONCLUSION

We propose a wire-driven SC design for ERCP using a multi-lumen seamless tube and two loop-formed control wires, different from the conventional SC design with a multiple-slit tube and single control wire. The SC prototype records balanced bidirectional bending with a maximum bending angle of ± 162° without breakage risk. The phantom and animal studies show that the prototype performance potentially facilitates papilla cannulations and intrahepatic ductal branch seeking.

Scissor-type knife precut in balloon enteroscopy-assisted ERCP for patients with difficult biliary cannulation and surgically altered anatomy (with video)

BACKGROUND AND AIMS

Balloon enteroscopy-assisted ERCP (BE-ERCP) is useful for treating pancreatobiliary disease in patients with surgically altered anatomy (SAA); however, biliary cannulation, including the precut technique, is often challenging. This study aimed to examine the feasibility of scissor-type knife precutting (SKP) during BE-ERCP in patients with SAA.

METHODS

This retrospective study investigated consecutive patients who underwent BE-ERCP and SKP for difficult biliary cannulation between 2016 and 2021. The study outcomes included the technical success and adverse event rates associated with SKP during BE-ERCP.

RESULTS

During the study period, 125 patients with native duodenal papillae underwent BE-ERCP, and the papilla was reached in 116 patients. The success rate of biliary cannulation with the standard cannulation approach alone was 67.2% (78/116), which increased to 77.6% (90/116) with the inclusion of advanced cannulation techniques besides precutting and further improved to 87.9% (102/116) with the addition of needlife precutting. SKP was attempted in 12 patients in whom all other cannulation approaches were difficult or resulted in failure. The technical success rate of SKP was 66.7% (8/12); thus, SKP increased the final success rate of biliary cannulation to 94.8% (110/116). The rate of adverse events associated with SKP was 8.3% (1/12).

CONCLUSIONS

This is the first study to report the use of the SKP technique for difficult biliary cannulation in patients with SAA, which may serve as a useful option for salvage cannulation during BE-ERCP.

Cytological Examination of Secretions From the Paranasal Sinuses in Horses

The objective of this study was to determine whether the assessment of cytological features of secretions from the paranasal sinuses represents a useful diagnostic tool in equine sinusitis to distinguish between different etiologies. Secretion samples from 50 horses with sinusitis and 10 healthy horses were taken transendoscopically from the drainage angle of the nasomaxillary aperture using a Swing Tip catheter. An additional direct sample from the caudal maxillary sinus was taken from all healthy horses after trephination. A direct sample was obtained from the affected sinus in 19 diseased horses after osteotomy. Samples were smeared on microscope slides and dyed using "Pappenheim stain" for cytological evaluation. Smears from horses with sinusitis (primary n = 14, dental n = 28, cyst n = 2, progressive ethmoidal hematoma [PEH] n = 2, traumatic n = 2, malignant neoplasia n = 2) were dominated by moderate to high numbers of neutrophilic granulocytes and moderate numbers of different epithelial cells, whereas samples from healthy sinuses revealed almost exclusively epithelial cells. Smears in dental-related sinusitis tended to contain more lytic cellular material than in other conditions. Horses with dental sinusitis also showed a higher intracellular and extracellular bacterial burden than horses with other underlying etiologies and healthy horses. The absence of bacteria in light microscopy did not exclude the evidence of pathogenic bacteria from bacterial culture in every case. Case numbers were too small to evaluate the diagnostic value for neoplastic conditions or PEH. In conclusion, cytological examination of secretions from the paranasal sinuses can provide an additional but limited ancillary diagnostic value in equine sinusitis.

Usefulness of a Cannula with a Flexible Tip (Swing Tip) for Managing Severe Biliary Stricture

BACKGROUND AND AIMS

Biliary stenting for the treatment of biliary stricture is the most common indication of ERCP, but the procedure is sometimes unsuccessful because of severe strictures. The Swing Tip is useful for passing through severe strictures because it has a manually operable tip. The efficacy of using a Swing Tip was retrospectively evaluated.

METHODS

The 2353 patients who underwent ERCP for biliary stenting at our facility between January 2012 and July 2018 were enrolled. In all patients, procedures were begun using tapered tip-catheters, and Swing Tips were used if the procedure was found to be difficult with other devices. The indication for switching to the Swing Tip and the technical success rate were retrospectively evaluated.

RESULTS

A total of 99 patients (4.2%) underwent ERCP using the Swing Tip, including 49 patients for the selection of biliary branches and 50 for exchanging guidewires for rigid ones. In these patients, biliary stenting was successful in 22 patients (44.9%) and 45 patients (90%), respectively. The other 32 patients with failed endoscopic biliary drainage were treated via alternative approaches, such as percutaneous procedures, surgeries, or conservative treatments. There were no adverse events associated with the Swing Tip.

CONCLUSION

The Swing Tip was technically feasible especially for exchanging guidewires during ERCP. Percutaneous procedures or surgical treatments can be avoided by using the Swing Tip.

ETHICAL STATEMENTS

This study was approved by the institutional review board of Okayama University. All subjects provided informed consent. The study was registered in the UMIN protocol registration system (identification number UMIN 000033692).

A prospective study on the microbiological examination of secretions from the paranasal sinuses in horses in health and disease

BACKGROUND

Diagnostics in equine sinusitis can be challenging and often require a combination of different imaging tools to ascertain its underlying aetiology. The bacterial flora of healthy and diseased paranasal sinuses, respectively, has only sporadically been assessed in horses. The objectives of this study were to determine whether assessment of microbiological features of secretions from the paranasal sinuses displays a useful diagnostic tool in equine sinusitis to distinguish between different aetiologies. Secretion samples from 50 horses with sinusitis and from 10 healthy horses were taken transendoscopically from the drainage angle of the nasomaxillary aperture using a guidable Swing Tip catheter. Bacteria found in healthy and diseased equine sinuses were compared. Endoscopic samples in all healthy and 19 diseased horses were compared with samples taken directly from the affected sinus after trephination.

RESULTS

Eleven of the 14 horses with primary sinusitis revealed growth of Streptococcus equi ssp. zooepidemicus, with three samples yielding pure cultures. Anaerobes were found in 15 out of 26 samples from horses with dental sinusitis. Healthy sinuses revealed mainly α-haemolytic streptococci and coagulase-negative staphylococci or showed no growth. Enterobacteriaceae were found more frequently in secondary sinusitis. There were significant differences in the bacterial composition and diversity (P < 0.05) between primary sinusitis, dental sinusitis and healthy controls. The correlation between endoscopic and trephination samples was satisfying.

CONCLUSIONS

Microbiological examination of secretions from horses with sinusitis collected transendoscopically can help to distinguish between primary and dental sinusitis. Therefore, it may display a feasible ancillary diagnostic tool, but does not replace a meticulous examination procedure including diagnostic imaging.

Utility of endoscopic retrograde cholangiopancreatography on biliopancreatic diseases in patients with Billroth II-reconstructed stomach

AIM

To examine the utility of endoscopic retrograde cholangiopancreatography (ERCP) on biliopancreatic diseases in the patients with Billroth II-reconstructed stomach.

METHODS

For 26 cases of biliopancreatic diseases in patients with Billroth II-reconstructed stomach, ERCP was conducted using a straight-view scope or a retrograde oblique-viewing endoscope. All the cases were patients aiming at selective insertion into the bile duct. One patient aimed at diagnosis, and 25 patients aimed at treatment. The cases in which the endoscope reached the duodenal papilla and anastomosis, and insertion into the bile duct became possible, were considered successful.

RESULTS

The rate of reaching the duodenal papilla and anastomosis was 84.7% (22/26 patients). Among the cases without reaching the duodenal papilla and anastomosis, there were 2 in which the endoscope did not pass due to tumor-induced duodenal infiltration. In 1 case, the fiber did not reach the duodenal papilla due to long afferent loop. The success rate of insertion into the bile duct in patients in which the endoscope reached the duodenal papilla and anastomosis was 90.9% (20/22 patients), and the success rate of procedures including treatment was 86.3% (19/22 patients). After treatment, mild cholangitis was observed in 1 patient (4.5%, 1/22 patients) but relieved conservatively. No other accidental symptom was observed.

CONCLUSION

It was considered that the ERCP for biliopancreatic diseases in patients with Billroth II-reconstructed stomach will become a less invasive, safe and useful examination and treatment approach.

Endoscopic Management of Biliary Leaks and Strictures After Living Donor Liver Transplantation: Optimizing Techniques for Successful Management

BACKGROUND AND AIMS

Biliary complications (BCs) occur in up to 40% of living donor liver transplant (LDLT) recipients. The aim of this study was to evaluate the efficacy of endoscopic therapy in the management of LDLT-related BCs.

METHODS

A retrospective study of 100 LDLT recipients at a single transplant center over a 9-year period was conducted. BC was defined as a biliary leak and/or a stricture. Patient records were used to identify time to diagnosis, type of intervention, and time to resolution.

RESULTS

BCs occurred in 46 (46%) patients; median follow-up was 4.6 years (range 5 days-9.3 years); and median time to diagnosis was 37.5 days (range 1 day-3.5 years). BCs were classified as a leak in 6 (6%), stricture in 22 (22%), and a leak + stricture in 18 (18%). ERCP was the initial treatment modality in 43/46 (93%) patients and was completed in 42/43 (98%). Three (6.5%) patients with a leak underwent surgery as the primary treatment approach. The median time to resolution of BCs was 91.5 days (range 21-367). Thirteen patients had a recurrence which was managed with endoscopic therapy alone.

CONCLUSIONS

Endoscopic therapy was successful in almost all patients (98%) and ERCP alone resulted in successful treatment in a higher proportion of patients (93%) than traditionally reported. Advanced endoscopic techniques obviate the need for PTC and/or surgery and allow successful management in almost all LDLT recipients presenting with BC and in patients with recurrence of strictures.

Difficult biliary access at ERCP

Endoscopic retrograde cholangiopancreatography allows intervention for a variety of diseases of the biliary tract. Cannulation of the bile duct is the prerequisite step for biliary intervention. Although obtaining biliary access is straightforward in many cases, it can occasionally be challenging. Multiple devices, all with additional wire-guided techniques, have been developed to aid cannulation. More advanced techniques have also been developed to aid biliary access if it is unsuccessful with standard devices. Multimodality techniques can be used if other approaches fail. This article provides an evidence-based discussion of these approaches, and provides insight into their appropriate application.

Advanced cannulation technique and precut

For most ERCP endoscopists, the greatest hurdle to a successful procedure is deep cannulation of the bile duct. This article explores basic cannulation technique, then reviews a variety of instruments and techniques designed to increase the average endoscopist's success rate. Expert ERCP endoscopists have a few favorite techniques that have proved reliable over time. The most frequently used ones are highlighted in this review.

New cannulation method for pancreatic duct cannulation-bile duct guidewire-indwelling method

The patient was a 58-year-old male with symptomatic alcoholic chronic pancreatitis. Since a 10 mm calculus was observed in the pancreatic body and abdominal pain occurred due to congestion of pancreatic juice, endoscopic retrograde cholangiopancreatography was conducted for assessment of the pancreatic duct and treatment of pancreatic calculus. Pancreatogram was slightly and insufficiently obtained by injecting the contrast media via the common channel of the duodenal main papilla. We tried to cannulate selectively into the pancreatic duct for a clear image. However, the selective cannulation of the pancreatic duct was difficult because of instability of the papilla. On the other hand, selective cannulation of the bile duct was relatively easily achieved. Therefore, after the imaging of the bile duct, a guidewire was retained in the bile duct to immobilize the duodenal papilla and cannulation of the pancreatic duct was attempted. As a result, selective pancreatic duct cannulation became possible. It is considered that the bile duct guidewire-indwelling method may serve as one of the useful techniques for cases whose selective pancreatic duct cannulation is difficult (“selective pancreatic duct difficult cannulation case”).

Anaesthetic considerations during endoscopic retrograde cholangiopancreatography

Endoscopic retrograde cholangiopancreatography has evolved from being a simple diagnostic procedure, performed under proceduralist-administered sedation, to a therapeutic one involving increasingly complex techniques that require a high degree of patient cooperation. The anaesthetist has become a vital member of the team. Many of the patients are medically unfit for surgery. Sedation or general anaesthesia is generally indicated for the increasingly complex, long and painful procedures being performed. Although there is very little published evidence of specific anaesthetic techniques in this area, knowledge of these problems allows the anaesthetist to select an appropriate technique to provide safe and effective anaesthesia.