Towards real-time PGS range monitoring in proton therapy of prostate cancer.

Proton therapy of prostate cancer (PCPT) was linked with increased levels of gastrointestinal toxicity in its early use compared to intensity-modulated radiation therapy (IMRT). The higher radiation dose to the rectum by proton beams is mainly due to anatomical variations. Here, we demonstrate an approach to monitor rectal radiation exposure in PCPT based on prompt gamma spectroscopy (PGS). Endorectal balloons (ERBs) are used to stabilize prostate movement during radiotherapy. These ERBs are usually filled with water. However, other water solutions containing elements with higher atomic numbers, such as silicon, may enable the use of PGS to monitor the radiation exposure of the rectum. Protons hitting silicon atoms emit prompt gamma rays with a specific energy of 1.78 MeV, which can be used to monitor whether the ERB is being hit. In a binary approach, we search the silicon energy peaks for every irradiated prostate region. We demonstrate this technique for both single-spot irradiation and real treatment plans. Real-time feedback based on the ERB being hit column-wise is feasible and would allow clinicians to decide whether to adapt or continue treatment. This technique may be extended to other cancer types and organs at risk, such as the oesophagus.

Small bowel polyp resection using device-assisted enteroscopy in Peutz-Jeghers Syndrome: Results of a specialised tertiary care centre.

INTRODUCTION: Enteroscopy resection of small bowel polyps in Peutz-Jeghers syndrome has only been described in small case series. Herein, we aimed to assess the efficacy of enteroscopy resection of small bowel polyps within a specialised tertiary care centre and the impact on intraoperative enteroscopy. METHODS: This was an observational single-centre study. All adult Peutz-Jeghers syndrome patients followed in the Predisposition Digestive Ile-de-France network who underwent an endoscopic resection of at least one small bowel polyp ≥ 1 cm by enteroscopy between 2002-2015 were included. Small bowel polyps were detected under a dedicated screening programme by previous capsule endoscopy and/or magnetic resonance enterography, performed every 2-3 years. Complete treatment was defined as the absence of polyps ≥ 1 cm after conventional endoscopic resection. Intraoperative enteroscopy or surgical resection were indicated in incomplete treatments. The overall complete treatment rate including conventional enteroscopy and intraoperative enteroscopy was also considered. RESULTS: Endoscopic resection of 216 small bowel polyps (median: 8.6 per patient, size: 6-60 mm) was performed by 50 enteroscopies in 25 patients (mean age: 36 years, range: 18-71, 56% male) with small bowel polyp ≥ 1 cm. Twenty-three patients (92%) underwent 42 screening capsule endoscopies and 14 (57%) had 23 magnetic resonance enterographies during a median follow-up of 60 months. Complete treatment was achieved in 76%. Intraoperative enteroscopy and surgical resection were performed in four (16%) and two (8%) patients. Intraoperative enteroscopy improved by 16% the complete treatment rate and the overall rate was 92%. The complication rate was 6%. CONCLUSION: This long-term study confirmed the efficacy and safety of endoscopic resection of small bowel polyps in Peutz-Jeghers syndrome. Intraoperative enteroscopy can be a complementary approach in selected cases.

[Optimal Bowel Preparation for Capsule Endoscopy and Device-assisted Enteroscopy].

For improved examination of video capsule endoscopy (VCE) and device-assisted enteroscopy (DAE), bowel preparation is an essential issue. Multiple factors like air bubbles, food material in the small bowel, and gastric and small bowel transit time affect the small bowel visualization quality (SBVQ), diagnostic yield (DY) and cecal completion rate (CR). Bowel preparation with polyethylene glycol (PEG) solution enhances SBVQ and DY, but it has no effect on CR. Bowel preparation with PEG solution 2 L is similar to PEG 4 L in SBVQ, DY, and CR. Bowel preparation with fasting or PEG solution combined with anti-foaming agents like simethicone enhance SBVQ, but it has no effect on CR. Bowel preparation with prokinetics is not commonly recommended. Optimal timing for purgative bowel preparation has yet to be established. However, the studies regarding bowel preparation for DAE are not sufficient. European Society of Gastrointestinal Endoscopy (ESGE) recommends 8-12 hours fasting from solid food and 4-6 hours fasting from liquids prior to the antegrade DAE. For retrograde DAE, colonoscopy preparation regimen is recommended. This article reviews the literature and ESGE, 2013 Korean published guidelines regarding bowel preparation for VCE and DAE, following suggestion for optimal bowel preparation for VCE and balloon enteroscopy.

Efficacy of a modified double-guidewire technique using an uneven double lumen cannula (uneven method) in patients with surgically altered gastrointestinal anatomy (with video).

BACKGROUND: Balloon enteroscopy-assisted endoscopic retrograde cholangiopancreatography (BE-ERCP) has been reported to be effective for patients with surgically altered gastrointestinal anatomy. However, selective biliary cannulation remains difficult in BE-ERCP. We examined the usefulness of a modified double-guidewire technique using an uneven double lumen cannula (the uneven method) for BE-ERCP in patients with surgically altered gastrointestinal anatomy. METHODS: To clarify the usefulness of the uneven method for selective biliary cannulation in BE-ERCP in comparison to the pancreatic guidewire (PGW) method, 40 patients with surgically altered gastrointestinal anatomy who underwent BE-ERCP with successful placement of a guidewire in the pancreatic duct were evaluated. The uneven method was used in 18 cases (uneven group) and the PGW method was used in the remaining 22 cases (PGW group). RESULTS: The technical success rate of biliary cannulation was higher in the uneven group than in the PGW group (83.3 vs. 59.0%; P = 0.165). In addition, the time to biliary cannulation were significantly shorter in the uneven group than in the PGW group (6 vs. 18 min; P = 0.004; respectively). In the PGW group, post-ERCP pancreatitis (PEP) occurred in 3 of 22 cases (13.6%). No adverse events, including PEP, occurred in the uneven group. CONCLUSIONS: The uneven method may be a useful option of selective biliary cannulation in BE-ERCP for the patients with surgically altered gastrointestinal anatomy.

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.

Device-assisted enteroscopy: A review of available techniques and upcoming new technologies.

The advent of video capsule endoscopy into clinical routine more than 15 years ago led to a substantial change in the diagnostic approach to patients with suspected small bowel diseases, often indicating a deep enteroscopy procedure for diagnostical confirmation or endoscopic treatment. Device assisted enteroscopy was developed in 2001 and for the first time established a practicable, safe and effective method for evaluation of the small bowel. Currently with double-balloon enteroscopy, single-balloon enteroscopy and spiral enteroscopy three different platforms are available in clinical routine. Summarizing, double-balloon enteroscopy seems to offer the deepest insertion depth to the small bowel going hand in hand with the disadvantage of a longer procedural duration. Manual spiral enteroscopy seems to be a faster procedure but without reaching the depth of the DBE in currently available data. Finally, single-balloon enteroscopy seems to be the least complicated procedure to perform. Despite substantial improvements in the field of direct enteroscopy, even nowadays deep endoscopic access to the small bowel with all available methods is still a complex procedure, cumbersome and time-consuming and requires high endoscopic skills. This review will give an overview of the currently available techniques and will further discuss the role of the upcoming new technology of the motorized spiral enteroscopy (PowerSpiral).

A reliable detachable balloon that prevents abdominal cavity contamination during transrectal natural orifice transluminal endoscopic surgery.

OBJECTIVE: To evaluate the efficacy and safety of a detachable endoluminal balloon in the prevention of abdominal cavity contamination during transrectal natural orifice transluminal endoscopic surgery (NOTES). METHODS: The efficacy and safety of a detachable endoluminal balloon to maintain disinfection in the distal colon of the pigs were evaluated. The bacterial loads and colonic cleanliness were monitored. Additionally, the device was applied to another nine pigs that underwent a cholecystotomy by transrectal NOTES. Necropsy and pathological examination were performed after 28-day follow-up. RESULTS: All animals exposed to the device and one of the seven pigs not exposed to the device scored three points on the bowel cleanliness scale (P < 0.001). After 30 min bacterial loads of the test (with balloon occlusion) and control (without balloon occlusion) groups showed a significant difference (0.8 × 103 CFU/mL vs 186.8 × 103 CFU/mL, P < 0.01). Cholecystotomy by transrectal NOTES with the device was successfully performed. The mean intraperitoneal procedure time was 102.9 ± 37.7 min. There were no procedure-related adverse events. During the follow-up, all animals presented normal behavior and appetite. No peritoneal infection or adhesion was detected at autopsy. Cholecystotomy and rectal incision were histologically healed and no histological abnormalities were detected in the colon related to balloon placement. CONCLUSIONS: The detachable balloon provides a reliable solution for preventing peritoneal contamination during transluminal operations. The technique may assist in future transrectal NOTES.

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 treatment for patients with gastric outlet stricture and biliary obstruction in the absence of endoscopic ultrasound: a retrospective study.

BACKGROUND AND AIM: Endoscopic biliary drainage is difficult in patients with biliary obstruction combined with gastric outlet stricture (GOS). Endoscopic ultrasound is useful for such patients, but needs advanced technique and sophisticated equipment. This study aimed to evaluate the efficacy and safety of conventional endoscopic retrograde cholangiopancreatography (ERCP) in patients with GOS and biliary obstruction without the assistance of endoscopic ultrasound. PATIENTS AND METHODS: Seventy-four patients with GOS proximal to the ampulla and biliary obstruction, including 27 with benign GOS and 47 with malignant GOS, were retrospectively enrolled. Three conventional methods were used to pass through the stricture and allow the duodenoscope to reach the papilla: adjusting the endoscope, balloon dilation, and metal stent insertion. The uncovered metal stent insertion was applied only in patients with malignant GOS. The primary outcome evaluated was successful biliary drainage. RESULTS: No serious complications occurred during or after ERCP. The overall success rate of biliary drainage in the patients was 81.1%. The success rate of duodenoscopy insertion by endoscope adjustment, balloon dilation, and stent insertion was 44.6, 68.9, and 71.4%, respectively. Endoscope adjustment was more successful in the patients in the benign group compared with the patients in the malignant group (60.9 vs. 35.7%). Similar findings were obtained for balloon dilation (92.3 vs. 59.4%). CONCLUSION: Most GOS, encountered during ERCP, can be safely dealt with using conventional endoscopic approaches in patients with biliary obstruction. However, the efficacy of endoscope adjustment or balloon dilation is better for benign GOS than for malignant GOS.

[Use of esophageal small balloon or papillary sphincter knife in the treatment of stent implantation for colorectal malignant obstruction].

OBJECTIVE: To explore the function of esophageal small balloon or papillary sphincter knife in the treatment of stent implantation for colorectal malignant obstruction, and to improve the success rate of colonic stent placement in such patients.
 Methods: A total of 49 patients with colorectal cancer complicated with almost complete obstruction or colorectal cancer were enrolled for this study. The esophageal small balloon or papillary sphincter knife was used in the guide wires. The guide wires gradually crossed the tumor gap and they were placed in the contralateral intestinal cavity with balloon progression. X-ray was then used to confirm whether the guide wire was inserted in the lesion intestinal cavity, and then the metal bare stent was inserted.
 Results: The guide wires was successfully inserted with conventional methods in these 49 cases, while they were also successfully placed the guide wire and the stent in the new way.
 Conclusion: For the patients with colorectal cancer complicated with complete obstruction or colorectal cancer located in obviously angled location, the use of esophageal small balloon or papillary sphincter knife can help the guide wire insert. They greatly improve the success rate of stent implantation.

A Deeper Look at the Small Bowel: Training Pathways in Video Capsule Endoscopy and Device-Assisted Enteroscopy.

BACKGROUND: Although there are guidelines for video capsule endoscopy (VCE) and device-assisted enteroscopy (DAE), little is known about fellowship training in these technologies. AIMS: The aims were to better characterize current small bowel endoscopy training in 3-year GI fellowship programs and 4th-year advanced endoscopy programs in the U.S. METHODS: We developed an online multiple-choice survey to assess current GI fellowship program training in small bowel endoscopy. The survey was distributed via email to GI fellowship program directors in the U.S. RESULTS: Of the 168 program directors contacted, 59 responded (response rate = 35.1%). There was no statistically significant difference in the availability of VCE or DAE between respondents and non-respondents. VCE training was universally available in 3-year training programs, with 84.8% (50/59) requiring it for fellows. The majority of 3-year GI fellows graduated with independence in VCE: 83.1% (49/59) of programs reported "most" or "all" graduates were able to read independently. DAE techniques were available in 86.4% of training programs (51/59). Training in DAE was more limited and shared between 3-year and 4th-year programs: 12.1% (7/58) of 3-year programs required training in DAE and 22.9% (8/35) of 4th-year programs required training in DAE . CONCLUSIONS: Training in VCE is widely available in U.S. GI fellowship programs, although programs have different ways of incorporating this training into the curriculum and of measuring competency. While DAE technology was available in the majority of programs, training was less frequently available, and training is shared between 3-year fellowship programs and 4th-year advanced endoscopy programs .

A multicenter experience of through-the-scope balloon-assisted enteroscopy in surgically altered gastrointestinal anatomy.

BACKGROUND: Surgically altered gastrointestinal anatomy poses challenges for deep enteroscopy. Current overtube-assisted methods have long procedure times and utilize endoscopes with smaller working channels that preclude use of standard accessories. A through-the-scope balloon-assisted enteroscopy (TTS-BAE) device uses standard endoscopes with a large working channel to allow metallic and plastic stent insertion. We aim to determine the efficacy and safety of TTS-BAE in patients with altered surgical anatomy. METHODS: A retrospective, multicenter study of TTS-BAE in altered anatomy patients at two USA and one German institution was performed between January 2013 and December 2014. Type of anatomy, procedure indication and duration, adverse events, and target, technical, and clinical success were recorded. RESULTS: A total of 32 patients (mean age 54 years, Caucasian 81.6%, female 42.1%, mean BMI 25.4 kg/m2) underwent 38 TTS-BAE procedures. Thirty-two percent of cases had a prior attempt at conventional enteroscopy which failed to reach the target site. The target was successfully reached in 23 (60.5%) cases. Of the 23 cases that reached the intended target, 22 (95.7%) achieved technical success and 21 (91.3%) achieved clinical success. The median procedure time was 43 min. Target, technical, and clinical success rates for TTS-BAE-assisted ERCP (n = 31) were 58.1, 54.8 and 54.8%. Seven self-expandable metallic stents (five biliary, two jejunal) were attempted, and all successfully deployed. Adverse events occurred in 4 (10.4%) cases, including one luminal perforation. CONCLUSION: TTS-BAE is an alternative to overtube-assisted enteroscopy that is comparable in safety in patients with surgically altered anatomies. Technical success in the instances where the target had been reached was excellent. TTS-BAE confers an advantage over overtube-assisted enteroscopy as it can facilitate the deployment of self-expandable metallic stents in the biliary tree and deep small bowel.

A Case Series: Outcomes of Endoscopic Biliary Self-Expandable Metal Stent for Malignant Biliary Obstruction with Surgically Altered Anatomy.

BACKGROUND: Few studies have reported the outcomes of self-expandable metal stent (SEMS) placement for malignant biliary obstruction in patients with surgically altered anatomy. AIMS: To evaluate the outcomes of biliary metal stent placement with the use of a short-type single-balloon enteroscope (working length, 1520 mm; channel diameter, 3.2 mm) in such patients. METHODS: We retrospectively studied 13 malignant biliary obstructions treated by SEMS placement. Technical success rate, functional success rate, time to recurrent biliary obstruction (RBO), and complications were evaluated. RESULTS: Technical success rate was 100 % (13/13), functional success rate was 92 % (12/13), and the median time to RBO was 247 days (95 % CI 205.6-285.5). Complications comprised mild pancreatitis in one patient. Uncovered SEMSs were placed in three obstructions, partially covered SEMS in five obstructions, and fully covered SEMSs in five obstructions. Three stents occluded (two ingrowths and one mucosal hyperplasia), and one symptomatic distal stent migration occurred after more than 30 days from placement. CONCLUSIONS: A short-type single-balloon enteroscope was useful for the placement of various SEMS in this patient population with satisfactory outcomes.

Long-term rebleeding risk following endoscopic therapy of small-bowel vascular lesions with device-assisted enteroscopy.

BACKGROUND AND AIMS: The effectiveness of endoscopic therapy of small-bowel vascular lesions (SBVL) remains unclear as recent studies report high recurrence rates after 2 years of follow-up. This study aimed to evaluate the long-term rebleeding risk after endoscopic therapy of SBVL and to identify predictive factors of rebleeding. METHODS: This was a retrospective single-center series of patients with SBVL treated endoscopically between July 2007 and February 2015. Relevant data from patient files, capsule endoscopies, and enteroscopy reports were retrieved. The primary endpoint was long-term rebleeding and the secondary endpoints were risk factors for rebleeding and transfusion requirements. RESULTS: Thirty-five patients were included. Capsule endoscopies indicated angioectasias in 74.3% and blood in the remaining; angioectasias were found in 97.1% of enteroscopies. Rebleeding occurred in 40% of patients during a median follow-up of 23 months (interquartile range 9-43). The rebleeding rate at 1, 2, 3, 4, and 5 years was 32.7, 38.3, 46.0, 53.7, and 63.0%, respectively. Only the presence of high-risk comorbidities (aortic valve stenosis, chronic renal or liver disease, or Osler-Weber-Rendu syndrome) was associated with higher rebleeding (P=0.006) in the univariate and multivariate analyses, being 51.3%/67.6% at 1/3 years, compared with 6.7%/22.2% in patients without any of these comorbidities. Transfusion requirements decreased to 6.3 (0.0-6.0) packed red blood cells units the year after endoscopic therapy compared with 11.5 (2.0-17.0) in the previous year (P=0.002). CONCLUSION: More than half of the patients had rebleeding after 5 years of follow-up, although transfusion requirements decreased. Patients with high-risk comorbidities are more likely to rebleed.