Update in enteroscopy: New devices and new indications

Endoscopic treatment of biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants: Lessons learned from single-balloon enteroscopy-assisted ERCP

BACKGROUND

Endoscopic treatment of biliopancreatic pathology is challenging due to surgically altered anatomy after Whipple's pancreaticoduodenectomy. This study aimed to evaluate the feasibility and safety of single-balloon enteroscopy-assisted endoscopic retrograde cholangiopancreatography (SBE-ERCP) to treat biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants.

METHODS

We retrospectively analyzed 106 SBE-ERCP procedures in 46 patients with Whipple's variants. Technical and clinical success rates and adverse events were evaluated.

RESULTS

Biliary SBE-ERCP was performed in 34 patients and pancreatic SBE-ERCP in 17, including 5 with both indications. From a total of 106 SBE-ERCP procedures, 76 were biliary indication with technical success rate of 68/76 (90%) procedures and clinical success rate of 30/34 (88%) patients. Mild adverse event rate was 8/76 (11%), without serious adverse events. From a total of 106 SBE-ERCP procedures, 30 were pancreatic indication with technical success rate of 24/30 (80%) procedures (P = 0.194 vs. biliary SBE-ERCP) and clinical success rate of 11/17 (65%) patients (P = 0.016 vs. biliary SBE-ERCP). Mild adverse event rate was 6/30 (20%) (P = 0.194 vs. biliary SBE-ERCP), without serious adverse events. After SBE-ERCP failure, endoscopic ultrasound-guided drainage, percutaneous drainage and redo surgery were alternative therapeutic options.

CONCLUSIONS

Biliopancreatic pathology after Whipple's pancreaticoduodenectomy variants can be treated using SBE-ERCP without serious adverse events. Technical and clinical success rates are high for biliary indications, whereas clinical success rate of pancreatic indications is significantly lower. SBE-ERCP can be considered as first-line treatment option in this patient group with surgically altered anatomy.

Integrated Sensors for Soft Medical Robotics

Minimally invasive procedures assisted by soft robots for surgery, diagnostics, and drug delivery have unprecedented benefits over traditional solutions from both patient and surgeon perspectives. However, the translation of such technology into commercialization remains challenging. The lack of perception abilities is one of the obstructive factors paramount for a safe, accurate and efficient robot-assisted intervention. Integrating different types of miniature sensors onto robotic end-effectors is a promising trend to compensate for the perceptual deficiencies in soft robots. For example, haptic feedback with force sensors helps surgeons to control the interaction force at the tool-tissue interface, impedance sensing of tissue electrical properties can be used for tumor detection. The last decade has witnessed significant progress in the development of multimodal sensors built on the advancement in engineering, material science and scalable micromachining technologies. This review article provides a snapshot on common types of integrated sensors for soft medical robots. It covers various sensing mechanisms, examples for practical and clinical applications, standard manufacturing processes, as well as insights on emerging engineering routes for the fabrication of novel and high-performing sensing devices.

Patient Radiation Exposure during Enteroscopy-Assisted Endoscopic Retrograde Cholangiopancreatography in Surgically Altered Anatomy (with Video)

BACKGROUND

Fluoroscopy must be used cautiously during endoscopic retrograde cholangiopancreatography (ERCP). Radiation exposure data in patients with surgically altered anatomy undergoing enteroscopy-assisted ERCP (EA-ERCP) are scarce.

METHODS

34 consecutive EA-ERCP procedures were compared with 68 conventional ERCP (C-ERCP) procedures. Patient and procedure characteristics and radiation data were collected.

RESULTS

Surgical reconstructions were gastrojejunostomy, Roux-en-Y hepaticojejunostomy, Roux-en-Y total gastrectomy, Roux-en-Y gastric bypass and Whipple's duodenopancreatectomy. Procedures were restricted to biliary indications. Mean fluoroscopy time was comparable in both groups (370 ± 30 s EA-ERCP vs. 393 ± 40 s C-ERCP, p = 0.7074), whereas total mean radiation dose was lower in EA-ERCP (83 ± 6 mGy) compared to C-ERCP (110 ± 11 mGy, p = 0.0491) and dose area product (DAP) was higher in EA-ERCP (2216 ± 173 µGy*m2) compared to C-ERCP (1600 ± 117 µGy*m2, p = 0.0038), as was total procedure time (77 ± 5 min vs. 39 ± 3 min, p < 0.0001). Enteroscope insertion to reach the bile duct during EA-ERCP took 28 ± 4 min, ranging from 4 to 90 min. These results indicate that C-ERCP procedures are generally more complex, needing magnified fluoroscopy, whereas EA-ERCP procedures take more time for enteroscope insertion under wide field fluoroscopic guidance (increased DAP) with less complex ERCP manipulation (lower total radiation dose).

CONCLUSIONS

Radiation exposure during EA-ERCP in surgically altered anatomy is different as compared to C-ERCP. EA-ERCP takes longer with a higher DAP because of the enteroscope insertion, but with lower total radiation dose because these ERCP procedures are usually less complex.

Motorized Spiral Enteroscopy: to infinity and beyond?

With the advent of device-assisted enteroscopy (DAE) in the early 2000s, endoscopic access to the entire small bowel is possible nowadays (1). And yet, there is still room for improvement. Total enteroscopy remains a time-consuming procedure, often combining the antegrade (oral) and retrograde (anal) approach with only a reasonable chance to obtain complete endoscopy of the entire small bowel (2). Therefore, the aim is to go faster, deeper and to perform more advanced therapeutic interventions within the long and tortuous small bowel. Moreover, DAE was also shown to be effective to perform endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered anatomy and to complete colonoscopy in patients with previously incomplete conventional colonoscopy due to long dolichocolon (3). The latest DAE development is Motorized Spiral Enteroscopy (MSE), initially conceptualized as a manually driven rotational spiral overtube by Paul A. Akerman, and further developed and commercialized as a motorized spiral overtube by the Olympus Medical Systems Corporation (4). Initial feasibility trials have shown that MSE can compete with already available DAE techniques (single- and double-balloon enteroscopy) with regard to diagnostic yield and endotherapy within the small bowel (5,6). However, being a short type enteroscope of 168 cm (as compared to the 200 cm long single- and double-balloon enteroscopes), MSE appears to be even more effective in obtaining deep and total enteroscopy with a relatively short procedural duration (2,6). In addition, the working channel diameter is increased to 3.2 mm (as compared to 2.8 mm) with an extra irrigation channel, facilitating therapeutic interventions within the small bowel. This faster and deeper (but more aggressive) enteroscopy technique comes with the price of an increased risk of mucosal injuries (ranging from superficial bruising to laceration and even perforation) within the oesophagus and the small bowel, luckily remaining asymptomatic most of the time without any clinical consequence (6). So far, this promising new technique has the potential of becoming a gamechanger in the still evolving field of deep enteroscopy.

Management of Difficult Bile Duct Stones by Large Balloon, Cholangioscopy, Enteroscopy and Endosonography

Endoscopic management of bile duct stones is now the standard of care, but challenges remain with difficult bile duct stones. There are some known factors associated with technically difficult bile duct stones, such as large size and surgically altered anatomy. Endoscopic mechanical lithotripsy is now the standard technique used to remove large bile duct stones, but the efficacy of endoscopic papillary large balloon dilatation (EPLBD) and cholangioscopy with intraductal lithotripsy has been increasingly reported. In patients with surgically altered anatomy, biliary access before stone removal can be technically difficult. Endotherapy using two new endoscopes is now utilized in clinical practice: enteroscopy-assisted endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-guided antegrade treatment. These new approaches can be combined with EPLBD and/or cholangioscopy to remove large bile duct stones from patients with surgically altered anatomy. Since various endoscopic procedures are now available, endoscopists should learn the indications, advantages and disadvantages of each technique for better management of bile duct stones.

Predictors for Small Bowel Stenosis in Balloon-Assisted Enteroscopy

BACKGROUND

Predictors besides symptoms of obstruction indicating small bowel stenosis are little known.

AIMS

To detect predictors of small bowel stenosis in balloon-assisted enteroscopy.

METHODS

Over a 6-year period, 461 patients had enteroscopy for suspected small intestinal disease. Details of clinical manifestations, medical history, demographic characteristics, findings of examinations, information on enteroscopy, and treatment were retrospectively collected based on medical records. Small bowel stenosis was defined as stricture that over-tube cannot go through in enteroscopy. Univariate and multivariate analyses were performed to identify predictors for small bowel stenosis.

RESULTS

A total of 314 patients had definite diagnosis after enteroscopy, imaging modalities, and/or even surgical exploration. They were included in this study for analyses. Mean age for them was 48.2 years old (range 15-81 years). Small bowel stenosis was present in 59 patients (18.8%). Analyses showed that CT/MRI indicating stenosis was significantly associated with severe stenosis (p = 0.014) but insignificant related to general stenosis (p = 0.097). Predictive factors that accompanied stenosis were age ≥ 60 years (OR = 2.1, 95% CI 1.1-4.0), underweight (BMI ≤ 18.5) (OR = 3.4, 95% CI 1.4-8.4), symptoms of obstruction (OR = 3.6, 95% CI 1.8-7.4), and overt small bowel bleeding (OR = 0.5, 95% CI 0.2-0.9).

CONCLUSIONS

Small bowel stenosis more tended to occur to patients with symptoms of obstruction, no overt small bowel bleeding, age ≥ 60 years, or underweight.

[Interventional endoscopy in the gastrointestinal tract : Indications and limitations]

The spectrum of endoscopic techniques has been greatly enlarged in recent years. Lesions and also (iatrogenic) complications that required surgical procedures in the past can now often be treated endoscopically. Advances in endoscopic mucosal resection and submucosal dissection also enable the resection of large or laterally spreading polyps in the gastrointestinal tract. Full-thickness resection is also possible by means of specially designed clips. By the creation of a submucosal tunnel submucosal lesions can be completely excised and the muscle fibers of the lower esophageal sphincter can be endoscopically severed in achalasia patients. Endosonography-guided interventions have developed into the standard procedure for complicated pancreatitis and the use of cholangioscopy offers new therapeutic procedures for the bile and pancreatic ducts. In this continuing medical education article interventional endoscopic techniques are presented and critically evaluated.

Appraisal of Laparoscopic Common Bile Duct Explorations Using Balloon-Assisted Stone Extraction Method: Seventeen Years Experiences

Background: Balloon-assisted stone extraction (BASE) can be applied to remove the common bile duct (CBD) stones during laparoscopic CBD exploration (LCBDE). This study aimed to analyze the efficacy of BASE. Methods: A retrospective analysis of patients with CBD stone who underwent LCBDE using BASE from 2001 to 2017 was conducted. The outcomes of BASE and potential factor for failure of technique were also evaluated. Results: A total of 163 patients underwent LCBDE using BASE were enrolled. Success rate of BASE was 88.3% (144/163) and 19 (11.7%) patients with failed BASE underwent basket for lithotripsy additionally. The reason for aborting BASE were stone impaction (n = 6), small stone (n = 4), migration into intrahepatic duct (IHD) (n = 3), and others (n = 6). The overall success rate of stone clearance was 98.2% (160/163). The mean CBD diameter was 15.8 mm (range 7-34 mm), and the largest stone size was 13.8 mm (range 3-36 mm). The overall rate of complication related with procedure was 4.9% (8/163), including bile leakage in 2 patients (1.2%), bleeding in 2 patients (1.2%), and pancreatitis in 4 patients (2.4%). There was no procedure-related mortality. Conclusions: BASE for CBD stone is safe and effective technique for the treatment of CBD stones.

Double balloon enteroscopy improves ERCP success in patients with modified small bowel anatomy

OBJECTIVE:

The aim of this study was to evaluate the effect of double-balloon enteroscopy (DBE) on the success of endoscopic retrograde cholangiopancreatography (ERCP) procedures in patients with surgically modified gastrointestinal (GI) tract anatomy.

METHODS:

The medical records of patients who underwent ERCP in the Gastroenterology Department of Kocaeli University School of Medicine hospital between December 2008 and September 2014 were examined. From the patient group that was scheduled to undergo DBE-ERCP, the details of cases in which ERCP via standard duodenoscope or DBE-ERCP was performed during the same session because standard ERCP failed were included. Procedure parameters, outcomes, and complications related to the procedure in both groups were analyzed. Patients who underwent the DBE-ERCP procedure directly, those who underwent push enteroscopy, or gastroscopy to evaluate the GI tract anatomy before the day of ERCP, and who underwent DBE-ERCP on a day other than the initial ERCP session were excluded. Afferent loop intubation, access to the major papilla, selective cannulation, therapeutic success rates, and the effect of DBE on overall procedure success were evaluated.

RESULTS:

Fifty-one patients with a history of BII gastrojejunostomy and 11 patients with hepaticojejunostomy (with or without Roux-en-Y) were included in the study. In all patients, the ERCP procedure was initiated with a standard duodenoscope. If intubation of the afferent loop was unsuccessful in reaching the major papilla or enterobiliary anastomosis, DBE was used. In 30 (48.4%) of the 62 patients whose GI tract was anatomically altered, the duodenoscope was successfully advanced to the ampulla and 27 (43.5%) were cannulated successfully. Thirty-one patients underwent DBE-ERCP. DBE reached the ampulla or enterobiliary anastomosis in 30 patients (96.8%) and selective choledocus cannulation was achieved in all patients but 3 (90%), including 1 patient with a hepaticojejunostomy. The overall ERCP success rate increased from 43.5% (27/62) to 87.1% (54/62). Two perforations (1 during standard duodenoscopy and 1 with DBE-ERCP) were observed.

CONCLUSION:

The overall success rate of ERCP increased with use of the DBE technique in patients with small bowel anatomic variations that were the result of previous surgery.

Analysis of the ‘Endoworm’ prototype’s ability to grip the bowel in in vitro and ex vivo models

Access to the small bowel by means of an enteroscope is difficult, even using current devices such as single-balloon or double-balloon enteroscopes. Exploration time and patient discomfort are the main drawbacks. The prototype ‘Endoworm’ analysed in this paper is based on a pneumatic translation system that, gripping the bowel, enables the endoscope to move forward while the bowel slides back over its most proximal part. The grip capacity is related to the pressure inside the balloon, which depends on the insufflate volume of air. Different materials were used as in vitro and ex vivo models: rigid polymethyl methacrylate, flexible silicone, polyester urethane and ex vivo pig small bowel. On measuring the pressure–volume relationship, we found that it depended on the elastic properties of the lumen and that the frictional force depended on the air pressure inside the balloons and the lumen’s elastic properties. In the presence of a lubricant, the grip on the simulated intestinal lumens was drastically reduced, as was the influence of the lumen’s properties. This paper focuses on the Endoworm’s ability to grip the bowel, which is crucial to achieving effective endoscope forward advance and bowel folding.

Endoscopic ultrasonography and small-bowel endoscopy: Present and future

Over the last decade, impressive technological advances have occurred in ultrasonography and small-bowel endoscopy. Nowadays, endoscopic ultrasonography is an essential diagnostic tool and a therapeutic weapon for pancreatobiliary disorders. Capsule endoscopy and device-assisted enteroscopy have quickly become the reference standard for the diagnosis of small-bowel luminal diseases, thereby leading to radical changes in diagnostic and therapeutic pathways. We herein provide an up-to-date overview of the latest advances in endoscopic ultrasonography and small-bowel endoscopy, focusing on the emerging paradigms and technological innovations that might improve clinical practice in the near future.

Device-assisted enteroscopy: An update on techniques, clinical indications and safety

After more than 15 years since its introduction into clinical practice, indications for device-assisted enteroscopy have greatly expanded. Alongside the consolidated indications such as the diagnosis and treatment of small bowel bleeding, Crohn's disease, hereditary polyposis, small-bowel tumors and complicated celiac disease, device-assisted enteroscopy is nowadays largely used to perform endoscopic retrograde cholangiopancreatography in patients with altered anatomy, stent placement, retrieval of foreign bodies, direct insertion of jejunal feeding tubes, and in selected cases of incomplete colonoscopy. This has been made possible by the technical improvements of the enteroscopes and accessories and by the widespread use of the method. Device-assisted enteroscopy endotherapy currently offers a safe and effective alternative to major surgery and often represents the preferred option for treatment of small-bowel pathology. Its safety profile is favourable even in the elderly patient, provided that it is performed in high-volume and experienced centers. The evolution of the enteroscopy technique is a challenge for the future and could be facilitated by the new enteroscopes models. These prototypes need a thorough clinical and safety assessment especially for the complex therapeutic procedures. Large prospective, multicenter studies should be performed to assess whether the use of device-assisted enteroscopy leads to improved patients' long-term outcomes.

Severe Biliary Stricture Dilation Using the Soehendra Stent Retriever with a Short-Type Balloon Enteroscope in Patients with Surgically Altered Anatomies

BACKGROUND

Balloon enteroscopy (BE) can be used for endoscopic retrograde cholangiography (ERC) to treat biliary strictures in patients with surgically altered anatomies. However, biliary strictures, including bilioenteric anastomotic strictures, are often very severe and dilation catheters cannot pass through them. The Soehendra stent retriever (SSR) is like a screw drill and can be useful for dilating severe strictures, but the utility of SSR during BE-assisted ERC (BE-ERC) is unclear. This study aimed to examine the efficacy and safety of a dilation technique using the SSR during BE-ERC.

METHODS

Between 2014 and 2018, 28 patients with surgically altered gastrointestinal anatomies and severe biliary strictures underwent BE-ERC, and the SSR was used for the dilation procedures. We evaluated the technical success, therapeutic success, and adverse event rates associated with SSR dilation.

RESULTS

The technical success rate was 93% (26/28). The procedures undertaken on two patients with non-anastomotic strictures failed technically because the SSR was not long enough to reach the strictures. The therapeutic success rate was 96% (25/26) for the patients whose procedures were technically successful. The adverse event rate was 7% (2/28), and the adverse events were mild and improved with conservative management. No bleeding or duct perforations occurred.

CONCLUSIONS

Although the indications for using the SSR in patients with non-anastomotic strictures should be considered based on the distance between the tip of the scope and the stricture's location, SSR dilation may be a useful option during BE-ERC if a biliary stricture is very severe.

Endoscopic Ultrasound-Guided Biliary Drainage for Benign Biliary Diseases

Although endoscopic retrograde cholangiopancreatography (ERCP) is the first-line treatment for benign biliary diseases, this procedure is technically difficult in some conditions such as a surgically altered anatomy and gastric outlet obstruction. After a failed ERCP, a surgical or a percutaneous approach is selected as a rescue procedure; however, various endoscopic ultrasound (EUS)-guided interventions are increasingly utilized in pancreatobiliary diseases, including EUS-guided rendezvous for failed biliary cannulation, EUS-guided antegrade treatment for stone management, and EUS-guided hepaticogastrostomy for anastomotic strictures in patients with a surgically altered anatomy. There are some technical hurdles in EUS-guided interventions for benign biliary diseases owing to the difficulty in puncturing a relatively small bile duct and in subsequent guidewire manipulation, as well as the lack of dedicated devices. A recent major advancement in this field is the introduction of a 2-step approach, in which EUS-guided drainage is placed in the first session and antegrade treatment is performed in subsequent sessions. This approach allows the use of various techniques such as mechanical lithotripsy and cholangioscopy without a risk of bile leak. In summary, EUS-guided interventions are among the treatment options for benign biliary diseases; however, standardization of the procedure and development of a treatment algorithm are needed.

Endoscopic retrograde cholangiopancreatography in Roux-en-Y gastric bypass patients

Roux-en-Y gastric bypass surgery remains a popular surgical intervention worldwide to treat morbid obesity. It is effective and relatively safe. However, one of the results related to bariatric surgery-induced rapid weight loss is the development of biliary stones. Endoscopic removal of common bile duct stones is challenging in patients with Roux-en-Y gastric bypass reconstruction. The current review highlights the different endoscopic approaches of the biliopancreatic system to perform endoscopic retrograde cholangiopancreatography in patients with Roux-en-Y gastric bypass. A treatment algorithm is provided based on clinical indications.

Hypoxia-induced intestinal barrier changes in balloon-assisted enteroscopy

KEY POINTS

Balloon-assisted enteroscopy (BAE) is an emerging standard procedure by utilizing distensible balloons to facilitate deep endoscopy in the small and large intestine. Sporadic cases of bacteraemia were found after BAE. Balloon distension by BAE caused gut tissue hypoxia. The impact of balloon distension-induced hypoxia on intestinal barriers remains unclear. Murine models of BAE by colonic balloon distension showed that short- and long-term hypoxia evoked opposite effects on epithelial tight junctions (TJs). Short-term hypoxia fortified TJ integrity, whereas long-term hypoxia caused damage to barrier function. Our data showed for the first time the molecular mechanisms and signalling pathways of epithelial barrier fortification and TJ reorganization by short-term hypoxia for the maintenance of gut homeostasis. The findings suggest avoiding prolonged balloon distension during BAE to reduce the risk of hypoxia-induced gut barrier dysfunction.

ABSTRACT

Balloon-assisted enteroscopy (BAE) is an emerging standard procedure that uses distensible balloons to facilitate deep endoscopy. Intestines are known to harbour an abundant microflora. Whether balloon distension causes perturbation of blood flow and gut barrier dysfunction, and elicits risk of bacterial translocation remains unknown. Our aims were to (1) conduct a prospective study to gather microbiological and molecular evidence of bacterial translocation by BAE in patients, (2) establish a murine model of colonic balloon distension to investigate tissue hypoxia and intestinal barrier, and (3) assess the effect of short- and long-term hypoxia on epithelial permeability using cell lines. Thirteen patients were enrolled for BAE procedures, and blood samples were obtained before and after BAE for paired comparison. Four of the 13 patients (30.8%) had positive bacterial DNA in blood after BAE. Post-BAE endotoxaemia was higher than the pre-BAE level. Nevertheless, no clinical symptom of sepsis or fever was reported. To mimic clinical BAE, mice were subjected to colonic balloon distension. Local tissue hypoxia was observed during balloon inflation, and reoxygenation after deflation. A trend of increased gut permeability was seen after long-term distension, whereas a significant reduction of permeability was observed by short-term distension in the proximal colon. Human colonic epithelial Caco-2 cells exposed to hypoxia for 5-20 min exhibited increased tight junctional assembly, while those exposed to longer hypoxia displayed barrier disruption. In conclusion, sporadic cases of bacteraemia were found after BAE, without septic symptoms. Short-term hypoxia by balloon distension yielded a protective effect whereas long-term hypoxia caused damage to the gut barrier.

Predictors for outcomes and readmission rates following double balloon enteroscopy: a tertiary care experience

AIM

 The objectives of this study are to examine clinical characteristics of patients undergoing anterograde and retrograde double balloon enteroscopy (DBE) and to assess factors predicting positive diagnostic yield, therapeutic yield, and readmission.

METHODS

 We conducted a retrospective cohort study of patients (n = 420) who underwent DBE at a tertiary care center between 2012 and 2016 at a tertiary referral center. Measures of central tendency and frequency distributions were used for univariate analysis. Chi-square and t-test analyses were used to compare patient characteristics. Logistic regression was used to predict outcomes of interest.

RESULTS

 Of patients included in the study, 59 % were male with a mean age of 61.49 (SD = 15.15) Altered anatomy was noted in 14 %, while 5 % and 13 % of patients had end stage renal disease (ESRD) and current use of anticoagulation, respectively. The most common indication for DBE was obscure gastrointestinal bleed (OGIB) (33 %). Forty-nine patients had obscure and overt gastrointestinal bleeding (GIB) and 22 % had occult GIB with iron deficiency. The cohort's rate of positive diagnostic yield was 73 % and 35 % for therapeutic yield. The 30-day and 6-month readmission rates were both 11 %. A higher proportion of those readmitted were male (75 % vs 57 %, P  = 0.027) and had longer procedural time (38.68 vs 46.57, P  = 0.011). Likewise, occult GIB with iron deficiency anemia and iron deficiency alone (OR = 2.45, CI: 1.233 - 4.859, P  = 0.011), inpatient status (OR 2.42, CI 1.344 - 4.346, P  = 0.003), and longer procedural time (OR = 1.02, CI: 1.004 - 1.029, P  = 0.008) were associated positively with readmission.

CONCLUSION

 DBE procedures have relevant efficacy for both diagnostic and therapeutic yield while evaluating small bowel disease. Readmission rates are low and more in those with GI bleed and iron deficiency with longer index procedural times.