Colon capsule endoscopy: detection of colonic polyps compared with conventional colonoscopy and visualization of extracolonic pathologies.

BACKGROUND: Conventional colonoscopy (CC) is the gold standard for diagnostic examination of the colon. However, the overall acceptance of this procedure is low due to patient fears of complications or embarrassment. Colon capsule endoscopy (CCE) represents a minimally invasive, patient-friendly procedure that offers complete visualization of the entire intestine. OBJECTIVE: To assess the PillCam Colon 2 (Given Imaging Ltd, Israel) capsule with regard to feasibility, sensitivity and specificity for the detection of colonic pathologies and additional recorded extracolonic findings. METHODS: CCE was performed before CC in patients indicated for CC for known or suspected colonic disease. The results of both techniques were compared with regard to polyp detection. Additionally, bowel preparation and extracolonic pathologies were analyzed. RESULTS: Twenty-four patients (mean age 51.1 years) were included in the analysis. Visualization of the colon was complete in 23 CCs and 17 CCEs. No adverse events or major technical failures occurred. CC detected 47 polyps and CCE detected 43 polyps of any size (per-finding sensitivity 90.9%, specificity 67.6%). The accuracy of CCE in detecting polyp carriers was 81.5% (per-patient analysis). On average, the colon was adequately cleansed in 90.1% of patients. CCE identified esophageal, gastric and small bowel pathologies in seven (24%), nine (38%) and 14 (58%) patients, respectively. CONCLUSIONS: CCE proved to be technically feasible and safe. Acceptable sensitivity and moderate specificity levels in polyp detection were recorded. Bowel preparation was adequate in most patients. Because extracolonic pathologies were effectively visualized, new indications for the PillCam Colon 2 may be defined.

QuickView video preview software of colon capsule endoscopy: reliability in presenting colorectal polyps as compared to normal mode reading.

OBJECTIVE. Colon capsule endoscopy (CCE) proved to be highly sensitive in detection of colorectal polyps (CP). Major limitation is the time-consuming video reading. The aim of this prospective, double-center study was to assess the theoretical time-saving potential and its possible impact on the reliability of "QuickView" (QV), in the presentation of CP as compared to normal mode (NM). METHODS. During NM reading of 65 CCE videos (mean patient´s age 56 years), all frames showing CPs were collected and compared to the number of frames presented by QV at increasing QV settings (10, 20, ... 80%). Reliability of QV in presenting polyps <6 mm and ≥6 mm (significant polyp), and identifying patients for subsequent therapeutic colonoscopy, capsule egestion rate, cleansing level, and estimated time-saving potential were assessed. RESULTS. At a 30% QV setting, the QV video presented 89% of the significant polyps and 86% of any polyps with ≥1 frame (per-polyp analysis) identified in NM before. At a 10% QV setting, 98% of the 52 patients with significant polyps could be identified (per-patient analysis) by QV video analysis. Capsule excretion rate was 74% and colon cleanliness was adequate in 85%. QV´s presentation rate correlates to the QV setting, the polyp size, and the number of frames per finding. CONCLUSIONS. Depending on its setting, the reliability of QV in presenting CP as compared to NM reading is notable. However, if no significant polyp is presented by QV, NM reading must be performed afterwards. The reduction of frames to be analyzed in QV might speed up identification of candidates for therapeutic colonoscopy.

Perforation during esophageal dilatation: a 10-year experience.

BACKGROUND & AIM: Esophageal stenosis can be caused by malignant, postsurgical, benign diseases etc. Endoscopic treatment options consist primarily of balloon dilatation and bougination. Both interventions carry a certain risk of further complications such as perforations. We aimed to evaluate this risk in our patients. METHODS: Frequency, perforation rates, further diagnostics, therapy, outcome and underlying diseases in 368 patients who underwent endoscopic dilatation or bougination in a 10 year period were evaluated. RESULTS: Overall, 1497 endoscopic interventions were performed for treatment of esophageal stricture, causing 8 perforations (0.53% per intervention, 2.17% per patient) and one lethal outcome (0.05% per intervention, 0.27% per patient). In 1286 bouginations, 8 perforations (0.62%) and one death occurred (0.08%), whilst no perforation was noted during 211 balloon dilatations. Outcome of the 8 perforations was greatly influenced by co-morbidities, causing a prolonged hospitalization and the death of one patient. CONCLUSION: Although complication rates are fairly small, patients should be under supervision or in contact for 24-72 hours after each intervention. In cases where perforation is suspected, radiological examinations should be conducted early. The perforation rate and mortality per patient may be used for patient information. Therapy and prognosis depend on the cause of perforation, localization and size of the perforation site as well as concomitant diseases.

Cleaning of occluded biliary endoprostheses: is shockwave application an alternative to regular stent exchange?

Occlusion is the major limitation of plastic biliary endoprostheses (PBE), making regular stent exchange necessary. The aim of the in vitro analysis was to evaluate the cleansing effect of shockwave application (SWA) on occluded PBE. Thirty-five PBE removed from 24 patients were analyzed. Three hundred and fifty shockwave pulses were administered every 10 mm along the prosthesis stored in a liquid-filled latex balloon. Occlusion rates were measured before and after SWA. The cleansing rate was calculated in comparison to the native prosthesis. Mean occlusion rate was 76 ± 30% (Range 16-100%) before SWA. Cleansing effect was 47 ± 52% (0-100%) after SWA. Cleaning was complete (100%) in seven (20%) and satisfying (75-99%) in another seven prostheses. Degree of stent occlusion and indwelling time were significantly associated to the cleansing effect. In conclusion, SWA showed a limited cleaning effect in clogged PBE and is no suitable alternative for regular stent replacement to date.

Does heparin coating reduce encrustation of biliary plastic endoprostheses? A prospective randomized trial.

OBJECTIVE: Common bile duct stenting is widely performed for bridging benign and malignant obstructions. A major limitation is early stent occlusion making regular stent exchange necessary. Covalent binding of glycosaminoglycanes to polyethylene stents proved to reduce encrustation in urological implants. Since development of urological and biliary stent occlusion shows parallels, the aim of the study was to evaluate the efficacy of heparin coating of biliary endoprostheses in preventing encrustation. MATERIAL AND METHODS: In a prospective randomized trial, heparin-coated and native stents were endoscopically placed for almost 90 days on average. After removal, all stents were dried (50°C, 24 h), weighed and after longitudinal incision visible encrustation and discoloration recorded. Fifty-three patients (21 females/32 males, 70 ± 12 (42-87) years) were included; 13 patients (4 females/9 males, 58-79 years) completed the study according to the protocol. RESULTS: After removal, mean weight of encrustation in native stents was more than double as high as of covered stents (native: 37.9 ± 19.8 (16-93) mg; covered: 17.6 ± 6.7 (9-33) mg). In 12 of 13 cases, the encrustation weight of the native stent was higher than that of the corresponding covered stent in the same patient. Premature stent explantation became necessary in 3 of 13 native stents, because of recurrent jaundice or cholangitis but only in 1 of 13 covered stents. After longitudinal incision, the three uncovered stents showed excessive encrustation whereas no significant encrustation was found in the covered prosthesis. Altogether, covered stents showed less visible accumulation of clogging material and discoloration than native stents. CONCLUSIONS: Covalent bound heparin is highly effective in preventing encrustation of biliary polyethylene endoprostheses.

Cleaning of occluded pancreatic duct endoprostheses: a new indication for extracorporeal shock wave lithotripsy?

BACKGROUND: Pancreatic duct stenting is widely performed for bridging main pancreatic duct obstruction in patients with chronic pancreatitis. The major limitation is early stent occlusion, making regular stent exchange necessary. OBJECTIVE: To date, no measures are available to prevent stent occlusion. The aim of this study was to evaluate the cleansing effect of shock wave application (SWA) on occluded pancreatic duct stents in vitro. DESIGN: In vitro study. PATIENTS: We analyzed occlusion rates of 25 plastic endoprostheses removed from 21 patients with chronic pancreatitis. INTERVENTION: We administered 350 shock wave pulses every 10 mm along the prosthesis, which was stored in a latex balloon filled with gas-free physiologic saline solution, by using a pressure of 42 megapascals. MAIN OUTCOME MEASUREMENTS: After SWA, the occlusion rate was measured again, and the cleansing rate was calculated in comparison with the native prosthesis. RESULTS: The mean (± SD) occlusion rate was significantly reduced (64.7 ± 28.7 [15%-100%]) before SWA vs 9.8 ± 25.3 [0-100%]) after SWA; P = .038). In 16 of 25 prostheses (64%), cleaning was complete. Four of the remaining 9 prostheses (16%) showed satisfactory cleaning of 95%, on average. Residual clogging material was found mainly at the duodenal tip and the middle of the stent. No significant association was found between patient-related or stent-related parameters and the cleansing effect of SWA. LIMITATIONS: In vitro study design. CONCLUSION: SWA is effective in cleaning occluded pancreatic endoprostheses in vitro. Prolongation of stent placement seems possible if regular SWA is performed. Extracorporeal shock wave lithotripsy therefore might become a new indication for patients under treatment with pancreatic endoprostheses.

Interventional endoscopic therapy in chronic pancreatitis including temporary stenting: a definitive treatment?

OBJECTIVE: In the past 15 years there have been tremendous advances in endoscopic management of chronic pancreatitis (CP). However, the value of endoscopic pancreatic stenting is still debatable. MATERIAL AND METHODS: In 98 patients suffering from symptomatic CP (84 M, 14 F, 49+/-12, age range 23-83 years) endotherapy including temporary stenting of the pancreatic duct was performed. After final stent removal, indicating the primary end-point of endotherapy, 96 patients were followed for 35+/-28 (8 days-111) months. All data were assessed retrospectively. RESULTS: As well as other endoscopic procedures, a total of 358 prostheses were inserted in the pancreatic duct and left in place for 3+/-1 (1 day-11) months. Total stent treatment time was 10+/-10 (6 days-49) months. At 46+/-27 (4-111) months after limited endotherapy, 57 patients had no need for secondary intervention, two-thirds were even without further pain sensations. In 22 patients, surgical treatment and in 17 patients further endoscopic therapy became necessary, which was significantly correlated with continued alcohol consumption. CONCLUSIONS: Temporary stent placement as a part of interventional endoscopic therapy in CP shows a high rate of technical and long-term clinical success, with no need for secondary treatment in a remarkable number of patients. Continued cessation of alcohol consumption supports the treatment benefit significantly.

Pancreatic endoprostheses in chronic pancreatitis: criteria to predict stent occlusion.

BACKGROUND: Good clinical results of main pancreatic duct (MPD) stent placement in chronic pancreatitis (CP) are clouded by early stent occlusion. The aim of this study was to increase knowledge about stent occlusion and its effects on clinical symptoms, and to define criteria that enable the prediction of clogging. METHODS: A total of 100 pancreatic endoprostheses of 47 patients (32 men, 15 women; mean age, 53 years; standard deviation, 9 years) with CP were bench tested by simulating the pathophysiologically increased MPD pressure. The main study parameter was the reduction of water flow through clogged stents in comparison with native endoprostheses of identical type, length, and diameter. Major stent occlusion was defined as flow reduction by > or = 75%. The association between time to stent occlusion and stent- or patient-related variables was evaluated. RESULTS: Occlusion took place in nearly all endoprostheses (97%). No significant association of occlusion with clinical or blood parameters was found. Multifactorial analysis proved 4 risk factors for major stent occlusion: (A) stent diameter > 8.5F, (B) stent length > 8 cm, (C) female gender, (D) exocrine pancreatic insufficiency that required regular oral enzyme supplementation. According to the relative risk, these factors were given the following scores: A, 3 points; B to D, 2 points. Stents in patients with a score sum > 5 showed a significantly higher risk of major stent occlusion within 90 days. CONCLUSIONS: Stent clogging in CP seems to be an inevitable phenomenon. Because clinical and laboratory data do not reliably indicate clogging, stent removal or exchange should be performed in high-risk patients (score sum > 5) within 3 months.

Composition of clogging material in pancreatic endoprostheses.

BACKGROUND: Endoscopic management of chronic pancreatitis (CP), especially pancreatic stent placement, has made tremendous advances. However, good clinical results are hampered by rapid occlusion. The objective of this study was to understand mechanisms and materials that cause stent occlusion. METHODS: The clogging material of 50 lyophilized pancreatic endoprostheses (length 8.5 cm, range 5-14 cm, diameter 7-11F) from patients with CP was completely removed and weighed. Protein solubilization was achieved at pH 8.0 by using sodium dodecyl sulfate (SDS) and 2-mercaptoethanol in the presence of proteasome inhibitors. Proteins were separated by using a SDS-polyacrylamide gel electrophoresis. Protein identification was performed by the Western blot technique, as well as by mass spectrometry. Insoluble components were examined by polarized light microscopy and after staining (periodic acid-Schiff [PAS]). RESULTS: Clogging material was found in 49 prostheses, mainly at the duodenal flap (80%). More than a third of the prostheses contained visible calcium carbonate calculi. Light microscopy and PAS staining showed plant debris (80%), crystals (73.5%), and mucopolysaccharides (100%). The dry weight of clogging material (18 +/- 13 mg, range 3-72 mg) correlated significantly with the stent diameter ( p = 0.029) but not with any other stent- or patient-related criteria. Albumin, its degradation products, and lithostathine were identified as the main proteinaceous components. CONCLUSIONS: Almost all pancreatic stents had clogging material, predominantly located at the duodenal flap, which contained plant material, mucopolysaccharides, and crystals, as well as visible calcium carbonate calculi. Albumin and lithostathine may play an important role in the development of stent occlusion.

Pancreatic duct stones in chronic pancreatitis: criteria for treatment intensity and success.

BACKGROUND: The aim of the study was to evaluate interventional endoscopic management of pancreatic duct stones in patients with chronic pancreatitis by describing therapeutic methods and defining factors that predict technical success. METHODS: Records were retrospectively analyzed for 125 patients with symptoms caused by chronic pancreatitis with pancreatic duct stones (single 43, multiple 82) treated by interventional endoscopy, including extracorporeal shockwave lithotripsy. RESULTS: Technical success was achieved in 85% of patients (11 patients by mechanical lithotripsy, 114 by piezoelectric extracorporeal shockwave lithotripsy). There were no serious complications from lithotripsy. Univariate analysis disclosed a statistically significant association between treatment success and patient age as well as prepapillary location of stones. A greater therapeutic effort was necessary in patients with stones located in the tail of the pancreas, 2 or more stones, a stone 12 mm or more in diameter, or who have had a longer duration (>8 years) of the disease. However, with exception of the last parameter, correction for multiple testing of data removed statistical significance. CONCLUSIONS: Extracorporeal shockwave lithotripsy enhances endoscopic measures for treatment of pancreatic duct stones when mechanical lithotripsy fails. Middle-aged patients in the early stages of chronic pancreatitis with stones in a prepapillary location proved to be the best candidates for successful treatment. Unfavorable patient-related or morphologic factors can be compensated for through more intense efforts at therapy.