Update and latest advances in mechanisms and management of colitis-associated colorectal cancer

Colitis-associated colorectal cancer(CAC)is defined as a specific cluster of colorectal cancers that develop as a result of prolonged colitis in patients with inflammatory bowel disease(IBD).Patients with IBD,including ulcerative colitis and Crohn’s disease,are known to have an increased risk of developing CAC.Although the incidence of CAC has significantly decreased over the past few decades,individuals with CAC have increased mortality compared to individuals with sporadic colorectal cancer,and the incidence of CAC increases with duration.Chronic inflammation is generally recognized as a major contributor to the pathogenesis of CAC.CAC has been shown to progress from colitis to dysplasia and finally to carcinoma.Accumulating evidence suggests that multiple immune-mediated pathways,DNA damage pathways,and pathogens are involved in the pathogenesis of CAC.Over the past decade,there has been an increasing effort to develop clinical approaches that could help improve outcomes for CAC patients.Colonoscopic surveillance plays an important role in reducing the risk of advanced and interval cancers.It is generally recommended that CAC patients undergo endoscopic removal or colectomy.This review summarizes the current understanding of CAC,particularly its epidemiology,mechanisms,and management.It focuses on the mechanisms that contribute to the development of CAC,covering advances in genomics,immunology,and the microbiome;presents evidence for management strategies,including endoscopy and colectomy;and discusses new strategies to interfere with the process and development of CAC.These scientific findings will pave the way for the management of CAC in the near future.

Comparison of fecal calprotectin levels and endoscopic scores for predicting relapse in patients with ulcerative colitis in remission

BACKGROUND Although the usefulness of endoscopic scores,such as the Mayo Endoscopic Subscore(MES),Ulcerative Colitis Endoscopic Index of Severity(UCEIS),and Ulcerative Colitis Colonoscopic Index of Severity(UCCIS),and biomarkers such as fecal calprotectin(FC)for predicting relapse in ulcerative colitis(UC)has been reported,few studies have included endoscopic scores for evaluating the entire colon.AIM To compare the usefulness of FC value and MES,UCEIS,and UCCIS for predicting relapse in patients with UC in clinical remission.METHODS In total,75 patients with UC in clinical and endoscopic remission who visited our institution between February 2019 and March 2022 were enrolled.The diagnosis of UC was confirmed based on the clinical presentation,endoscopic findings,and histology,according to the current established criteria for UC.Fecal samples were collected the day before or after the colonoscopy for measurement of FC.Endoscopic evaluations were performed using MES,UCEIS,and UCCIS.The primary outcome measure of this study was the assessment of the association between relapse within 12 mo and MES,UCEIS,UCCIS,and FC.The secondary outcome was the comparison between endoscopic scores and biomarkers in en-rolled patients with UC with mucosal healing.RESULTSFC and UCCIS showed a significant correlation with UCEIS (r = 0.537, P < 0.001 and r = 0.957, P < 0.001, respectively).Receiver-operating characteristic analysis for predicting MES 0 showed that the area under the curve ofUCCIS was significantly higher than that of FC (P < 0.01). During the 1-year observation period, 18 (24%) patientsexperienced a relapse, and both the FC and UCCIS of the relapse group were significantly higher than that of theremission group. The cut-off values for predicting relapse were set at FC = 323 mg/kg and UCCIS = 10.2. The areaunder the curve of the receiver-operating characteristic analysis for predicting relapse did not show a significantdifference between FC and UCCIS. The accuracy of the endoscopic scores and biomarkers in predicting relapse was86.7% for UCCIS, 85.3% for UCEIS, 76.0% for FC, and 73.3% for MES.CONCLUSIONThe three endoscopic scores and FC may predict UC relapse during clinical remission. Among these scores, UCEISmay be the most useful in terms of ease of evaluation and accuracy.

New endoscopy devices to improve population adherence to colorectal cancer prevention programs

Despite recent advances in medicine,colorectal cancer (CRC)remains one of the greatest hazards for public health worldwide and especially the industrialized world.It has been well documented with concrete data that regular screening colonoscopy aimed at early detection of precancerous polyps can help decrease the incidence of CRC.However,the adherence of the general population to such screening programs has been shown to be lower than that expected,thus allowing CRC to remain a major threat for public health.Various reasons have been suggested to explain the disappointing compliance of the population to CRC screening programs,some of them associated with colonoscopy per se,which is viewed by many people as an unpleasant examination.Governments,medical societies,individual gastroenterologists,as well as the medical industry are working in order to improve endoscopic devices and/or to improve standard colo-noscopy.The aim is to improve the acceptance of the population for this method of CRC screening,by providing a painless and reliable examination of the colon.This review focuses on some of the latest improve-me-nts in this fie-ld.

Feasibility of full-spectrum endoscopy:Korea's first full-spectrum endoscopy colonoscopic trial

AIM: To evaluate the full-spectrum endoscopy(FUSE) colonoscopy system as the first report on the utility thereof in a Korean population.METHODS: We explored the efficacy of the FUSE colonoscopy in a retrospective, single-center feasibility study performed between February 1 and July 20, 2015. A total of 262 subjects(age range: 22-80) underwent the FUSE colonoscopy for colorectal cancer screening, polyp surveillance, or diagnostic evaluation. The cecal intubation success rate, the polyp detection rate(PDR), the adenoma detection rate(ADR), and the diverticulum detection rate(DDR), were calculated. Also, the success rates of therapeutic interventions were evaluated with biopsy confirmation.RESULTS: All patients completed the study and the success rates of cecal and terminal ileal intubation were 100% with the FUSE colonoscope; we found 313 polyps in 142 patients and 173 adenomas in 95. The overall PDR, ADR and DDR were 54.2%, 36.3%, and 25.2%, respectively, and were higher in males, and increased with age. The endoscopists and nurses involved considered that the full-spectrum colonoscope improved navigation and orientation within the colon.No colonoscopy was aborted because of colonoscope malfunction.CONCLUSION: The FUSE colonoscopy yielded a higher PDR, ADR, DDR than did traditional colonoscopy, without therapeutic failure or complications, showing feasible, effective, and safe in this first Korean trial.

New endoscopes and add-on devices to improve colonoscopy performance

Colonoscopy is the gold standard for colorectal cancer prevention; however, it is still an imperfect modality. Precancerous lesions can be lost during screening examinations, thus increasing the risk of interval cancer. A variety of factors either patient-, or endoscopist dependent or even the procedure itself may contribute to loss of lesions. Sophisticated modalities including advanced technology endoscopes and add-on devices have been developed in an effort to eliminate colonoscopy's drawbacks and maximize its ability to detect potentially culprit polyps. Novel colonoscopes aim to widen the field of view. They incorporate more than one cameras enabling simultaneous image transmission. In that way the field of view can expand up to 330°. On the other hand a plethora of add-on devices attachable on the standard colonoscope promise to detect lesions in the proximal aspect of colonic folds either by offering a retrograde view of the lumen or by straightening the haustral folds during withdrawal. In this minireview we discuss how these recent advances affect colonoscopy performance by improving its quality indicators(cecal intubation rate, adenoma detection rate) and other metrics(polyp detection rate, adenomas per colonoscopy, polyp/adenoma miss rate) associated with examination's outcomes.

Colonoscopic perforation:Incidence,risk factors,management and outcome

This review discusses the incidence,risk factors,management and outcome of colonoscopic perforation(CP).The incidence of CP ranges from 0.016% to 0.2% following diagnostic colonoscopies and could be up to 5% following some colonoscopic interventions.The perforations are frequently related to therapeutic colonoscopies and are associated with patients of advanced age or with multiple comorbidities.Management of CP is mainly based on patients' clinical grounds and their underlying colorectal diseases.Current therapeutic approaches include conservative management(bowel rest plus the administration of broadspectrum antibiotics),endoscopic management,and operative management(open or laparoscopic approach).The applications of each treatment are discussed.Overall outcomes of patients with CP are also addressed.

Risk factors for colonoscopic perforation: A population-based study of 80118 cases

AIM: To assess the incidence and risk factors associated with colonic perforation due to colonoscopy. METHODS: This was a retrospective cross-sectional study. Patients were retrospectively eligible for inclusion if they were 18 years and older and had an inpatient or outpatient colonoscopy procedure code in any facility within the Geisinger Health System during the period from January 1, 2002 to August 25, 2010. Data are presented as median and inter-quartile range, for continuous variables, and as frequency and percentage for categorical variables. Baseline comparisons across those with and without a perforation were made using the two-sample t -test and Pearson's χ2 test, as appropriate.RESULTS: A total of 50 perforations were diagnosed out of 80118 colonoscopies, which corresponded to an incidence of 0.06% (95%CI: 0.05-0.08) or a rate of 6.2 per 10000 colonoscopies. All possible risk factors associated with colonic perforation with a P -value < 0.1 were checked for inclusion in a multivariable logbinomial regression model predicting 7-d colonic perforation. The final model resulted in the following risk factors which were significantly associated with risk of colonic perforation: age, gender, body mass index, albumin level, intensive care unit (ICU) patients, inpatient setting, and abdominal pain and Crohn's disease as indications for colonoscopy. CONCLUSION: The cumulative 7 d incidence of colonic perforation in this cohort was 0.06%. Advanced age and female gender were significantly more likely to have perforation. Increasing albumin and BMI resulted in decreased risk of colonic perforation. Having a colonoscopy indication of abdominal pain or Crohn's disease resulted in a higher risk of colonic perforation. Colonoscopies performed in inpatients and particularly the ICU setting had substantially greater odds of perforation. Biopsy and polypectomy did not increase the risk of perforation and only three perforations occurred with screening colonoscopy.

Comparison of postpolypectomy bleeding between epinephrine and saline submucosal injection for large colon polyps by conventional polypectomy:A prospective randomized,multicenter study

AIM:To evaluate and compare the clinical outcomes of prophylactic submucosal saline-epinephrine injection and saline injection alone for large colon polyps by conventional polypectomy. METHODS:A prospective study was conducted from July 2003 to July 2004 at 11 tertiary endoscopic centers. Large colon polyps (> 10 mm in diameter) wererandomized to undergo endoscopic polypectomy with submucosal saline-epinephrine injection (epinephrine group) or normal saline injection (saline group). Endoscopic polypectomy was performed by the conventional snare method,and early (< 12 h) and late bleeding complications (12 h-30 d) were observed. RESULTS:A total of 561 polyps in 486 patients were resected by endoscopic polypectomy. Overall,bleeding complications occurred in 7.6% (37/486) of the patients,including 4.9% (12/244) in the epinephrine group,and 10.3% (25/242) in the saline group. Early and late postpolypectomy bleeding (PPB) occurred in 6.6% (32/486) and 1% (5/486) of the patients,respectively,including 4.5% (11/244),0.4% (1/244) in the epinephrine group,and 8.7% (21/242),1.7% (4/242) in the saline group. No significant differences in the rates of overall,early and late PPB were observed between the 2 groups. Multivariate stepwise logistic regression analysis revealed that large size (> 2 cm) and neoplastic polyps were independently and significantly associated with the presence of PPB. CONCLUSION:The prophylactic submucosal injection of diluted epinephrine does not appear to provide an additional advantage over the saline injection alone for the prevention of PPB.

Does flexible small-diameter colonoscope reduce insertion pain during colonoscopy?

AIM It is well known that colonoscopy can bedifficult due to abdominal pain induced duringcolonoscope insertion,if sedative agents are notgiven.Recently,an extra-flexible,small-diameter colonoscope(CF-SV,Olympus Inc.,Japan)was developed in order to improve safetyand comfort.The aim of this study was toaccess the usefulness of the CF-SV.METHODS One hundred patients undergoingsigmoidoscopy were recruited and colonoscopywas performed by one experiencedcolonoscopist.First,a routine-type colonoscope(CF-2301)was inserted into the colon withoutsedation.When the patient complained ofabdominal pain(even if mild),the scope wasnot advanced further and was withdrawn afterthe anatomic location of its tip was determinedfluoroscopically.Then,the CF-SV was inserteduntil it reached the cecun or the site whereabdominal pain occurred.Previous abdominalsurgery and abdominal disease were consideredas unfavorable factors(UF)and the relationshipbetween abdominal pain and UF,age and genderwere investigated.Furthermore,the colonicinsertion pressures in 36 patients with abdominalpain were measured with a force gauge.RESULTS Thirty-four cases(34%)felt no painwith the CF-2301 and successful pancolon-0scopies to the cecum were performed.Sixty-six cases(66%)complained of abdominal pain.The procedure was painless for 47% of men and24% of women,respectively.The CF-2301 scopefailed to reach the sigmoid-descending colon junctions in 59(89.4%)of the 66 patientscomplaining of abdominal pain.However,CF-SVreached proximal area in 94.9% of those whofailed with CF-2301.The median pressure forpain-inducing was 700 g/cm^2.CONCLUSION Unsedated patients with UFwere prone to complain of pain when thestandard-type CF-2301 scope was used.Thenewly developed extra-flexible CF-SV is usefulfor the aged and for those with UF or being proneto suffer from abdominal pain.Sedative agentsmay be unnecessary if this new type ofcolonoscope is used.

Magnetic endoscopic imaging vs standard colonoscopy:Meta-analysis of randomized controlled trials

AIM:To assess the theoretical advantages of magnetic endoscope imaging(MEI)over standard colonoscopies(SCs)and to compare their efficacies.METHODS:Electronic databases,including PubMed,EMBASE,the Cochrane library and the Science Citation Index,were searched to retrieve relevant trials.In addition,abstracts from papers presented at professional meetings and the reference lists of retrieved articles were reviewed to identify additional studies.The metaanalyses were performed using RevMan 5.1.A random effect model with the Mantel-Haenszel method was used for pooling dichotomous and continuous data.A sensitivity analysis was performed by excluding the trials with a small number of patients and by excluding the trials performed by inexperienced providers.RESULTS:Eight randomized controlled trials(RCTs),including 2967 patients,were included in the metaanalysis to compare cecal intubation rates and times,sedation dose,abdominal pain scores and the use of ancillary maneuvers between MEI and SC.The overall OR was 1.92(95%CI:1.13-3.27,eight RCTs),as indicated by the cecal intubation rate of MEI compared with SC,but MEI did not have any distinct advantage over SC for cecal intubation time(MD=-0.07,95%CI:-0.16-0.02;three RCTs).MEI did not generally result in lower pain scores.Outcomes were also analyzed for the two subgroups based on the endoscopists’experience level to evaluate cecal intubation rates.MEI presented better outcomes for non-experienced colonoscopists than experienced colonoscopists.CONCLUSION:The real-time magnetic imaging system is of benefit in training and educating inexperienced endoscopists and improves the cecal intubation rate for experienced and inexperienced endoscopists.

Colonoscopic perforation:A report from World Gastroenterology Organization endoscopy training center in Thailand

AIM： To determine the incidence of colonoscopic perforation （CP）, and evaluate clinical findings, management and outcomes of patients with CP from the World Gastroenterology Organization （WGO） Endoscopy Training Center in Thailand. METHODS： All colonoscopies and sigmoidoscopies performed between 1999 and 2007 in the Endoscopic unit, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok were reviewed. Incidence of CP, patients＇ characteristics, endoscopic information, intraoperative findings, management and outcomes were analyzed. RESULTS： A total of 17357 endoscopic procedures of the colon （13 699 colonoscopies and 3658 flexible sigmoidoscopies） were performed in Siriraj hospital over a 9-year period. Fifteen patients （0.09%） had CP： 14 from colonoscopy and 1 from sigmoidoscopy. The most common site of perforation was in the sigmoid colon （80%）, followed by the transverse colon （13%）. Perforations were caused by direct trauma from either the shaft or the tip of the endoscope （n = 12,80%） and endoscopic polypectomy （n = 3, 20%）. All patients with CP underwent surgical management： primary repair （27%） and bowel resection （73%）. The mortality rate was 13% and postoperative complication rate was 53%. CONCLUSION： CP is a rare but serious complication following colonoscopy and sigmoidoscopy, with high rates of morbidity and mortality. Incidence of CP was 0.09%. Surgery is still the mainstay of CP management.

When and why a colonoscopist should discontinue colonoscopy by himself?

AIM: To investigate when and why a colonoscopist should discontinue incomplete colonoscopy by himself.METHODS: In this cross-sectional study, 517 difficult colonoscope insertions(Grade C, Kudo's difficulty classification) screened from 37800 colonoscopy insertions were collected from April 2004 to June 2014 by three 4th-level(Kudo's classification) colonoscopists. The following common factors for the incomplete insertion were excluded: structural obstruction of the colon or rectum, insufficient colon cleansing, discontinuation due to patient's discomfort or pain, severe colon disease with a perforation risk(e.g., severe ischemic colonopathy). All the excluded patients were re-scheduled if permission was obtained from the patients whose intubation had failed. If the repeat intubations were still a failure because of the difficult operative techniques, those patients were also included in this study. The patient's age, sex, anesthesia and colonoscope type were recorded before colonoscopy. During the colonoscopic examination, the influencing factors of fixation, tortuosity, laxity and redundancy of the colon were assessed, and the insertion time(> 10 min or ≤ 10 min) were registered. The insertion time was analyzed by t-test, and other factors were analyzed by univariate and multivariate logistic regression.RESULTS: Three hundred and twenty-two(62.3%) of the 517 insertions were complete in the colonoscope insertion into the ileocecum, but 195(37.7%) failed in the insertion. Fixation, tortuosity, laxity or redundancy occurred during the colonoscopic examination. Multivariate logistic regression analysis revealed that fixation(OR = 0.06, 95%CI: 0.03-0.16, P < 0.001) and tortuosity(OR = 0.04, 95%CI: 0.02-0.08, P < 0.001) were significantly related to the insertion into the ileocecum in the left hemicolon; multivariate logistic regression analysis also revealed that fixation(OR = 0.16, 95%CI: 0.06-0.39, P < 0.001), tortuosity(OR0.23, 95%CI: 0.13-0.43, P < 0.001), redundancy(OR = 0.12, 95%CI: 0.05-0.26, P < 0.001) and sex(OR = 0.35, 95%CI: 0.20-0.63, P < 0.001) were significantly related to the insertion into the ileocecum in the right hemicolon. Prolonged insertion time(> 10 min) was an unfavorable factor for the insertion into the ileocecum.CONCLUSION: Colonoscopy should be discontinued if freedom of the colonoscope body's insertion and rotation is completely lost, and the insertion time is prolonged over 30 min.

Combined Use of Single-balloon Enteroscope and Colonoscope for Self-expandable Metal Stent Placement in Patients with Malignant Small Intestinal Obstruction: a Single-center Comparative Clinical Observation

Small intestinal obstruction is a common complication of primary gastrointestinal cancer or metastatic cancers. Patients with this condition are often poor candidates for surgical bypasses, and placement of self-expanding metal stent(SEMS) can be technically challenging. In this study, we examined the feasibility of combined application of single-balloon enteroscope(SBE) and colonoscope for SEMS placement in patients with malignant small intestinal obstruction. Thirty-four patients were enrolled in this study, among which 22 patients received SEMS placement by using SBE and colonoscope, while the other 12 patients received conservative medical treatment. The patients were followed up for one year. Stent placement was technically feasible in 95.5%(21/22). Clinical improvement was achieved in 86.4%(19/22). For the 19 clinical success cases, the average time of benefits from a gastric outlet obstruction scoring system(GOOSS) increase ≥1 was 111.9±89.5 days. For the 12 patients receiving conservative medical treatment, no significant improvement in GOOSS score was observed. Moreover, a significant increase of Short-Form-36 health survey score was observed in the 19 patients at time of 30 days after stent placement. By Kaplan-Meier analysis, a significant survival improvement was observed in patients with successful SEMS placement, compared with patients receiving conservative medical treatment. Taken together, combined use of SBE and colonoscope makes endoscopic stent placement feasible in patients with malignant small intestinal obstruction, and patients can benefit from it in terms of prolonged survival and improved quality of life.

Colonoscopy can miss diverticula of the left colon identified by barium enema

AIM: To identify the diagnostic value of colonoscopy for diverticulosis as determined by barium enema. METHODS: A total of 65 patients with hematochezia who underwent colonoscopy and barium enema were analyzed, and the diagnostic value of colonoscopy for diverticula was assessed. The receiver operating characteristic area under the curve was compared in relation to age (< 70 or ≥ 70 years), sex, and colon location. The number of diverticula was counted, and the detection ratio was calculated. RESULTS: Colonic diverticula were observed in 46 patients with barium enema. Colonoscopy had a sensitivity of 91% and specificity of 90%. No significant differences were found in the receiver operating characteristic area under the curve (ROC-AUC) for age group or sex. The ROC-AUC of the left colon was significantly lower than that of the right colon (0.81 vs 0.96, P=0.02). Colonoscopy identified 486 colonic diverticula, while barium enema identified 1186. The detection ratio for the entire colon was therefore 0.41 (486/1186). The detection ratio in the left colon (0.32, 189/588) was significantly lower than that of the right colon (0.50, 297/598) (P < 0.01). CONCLUSION: Compared with barium enema, only half the number of colonic diverticula can be detected by colonoscopy in the entire colon and even less in the left colon.

Which scope is appropriate for endoscopic retrograde cholangiopancreatography after Billroth II reconstruction:An esophagogastroduodenoscope or a colonoscope?

BACKGROUND Recently,with the advent of more advanced devices and endoscopic techniques,endoscopic retrograde cholangiopancreatography(ERCP)in Billroth II(B-II)patients has been increasingly performed.However,the procedures are difficult,and the techniques and strategies have not been defined.AIM To reveal the appropriate scope for ERCP in B-II patients.METHODS Sixty ERCP procedures were performed on B-II patients between June 2005 and May 2018 at Fukushima Medical University Hospital,and in 44 cases,this was the first ERCP procedure performed by esophagogastroduodenoscopy(EGDS)or colonoscopy(CS)after B-II gastrectomy.These cases were divided into two groups:17 cases of ERCP performed by EGDS(EGDS group)and 27 cases of ERCP performed by CS(CS group).The patient characteristics and ERCP procedures were compared between the EGDS and CS groups.RESULTS The procedural time was significantly shorter in the EGDS group than in the CS group[median(range):60(20-100)vs 90(40-128)min,P value<0.01].CS was an independent factor of a longer ERCP procedural time according to the univariate and multivariate analyses(odds ratio:3.97,95%CI:1.05-15.0,P value=0.04).CONCLUSION Compared to CS,EGDS shortened the procedural time of ERCP in B-II patients.

Intestinal pseudo-obstruction:An uncommon condition with heterogeneous etiology and unpredictable outcome

Intestinal pseudo-obstruction (IPO) either acute or chronic is a condition including features of intestinal ileus in absence of mechanical obstruction. Our paper presents such a rare case of idiopathic IPO in a 53-year-old male patient with recurrent episodes of pseudo-obstruction, which were successfully resolved by anticholinesterase agents, motilin agonists or colonic decompression. However, the patient finally underwent total colectomy. Huge colonic dilatation was identified intraoperatorily, while histology showed a neuropathic variant of chronic intestinal pseudo-obstruction. Etiologic mechanisms and current therapeutic methods are reviewed in this paper, which concludes that IPO is a condition in which conservative treatment usually fails. Total colectomy with ileoanal pouch may be the only solution in these situations.

Study on Active Drive System for Colonoscope

The paper deals with active drive system for colonoscope. The system is mainly composed of soft mobile mechanism for earthworm locomotion and turning mechanism based on shape memory effect. The soft mobile mechanism contacts colon wall with air in inflatable balloons, so the robot has better soft and non invasive properties. The turning mechanism can be actively bent by shape memory alloy components. It ensures the colonoscope to adapt to the tortuous shape of colon. Some experiment results are given in the paper.

Colonoscopically Assisted Laparoscopic Polypectomy–An Alternative to Right Hemicolectomy for Large Right-Sided Benign Polyps

Introduction: Laparoscopic assisted colonoscopic polypectomies have been well described in the literature and are well established in surgical practice, for removal of large, inaccessible, or flat based polyps. Laparoscope allows the endoscopist a serosal viewpoint and thus clear indication of perforation, in addition to enhancing endoscopic positioning through colonic mobilisation, facilitating polypectomy. We describe a previously rarely published technique, in which the colonoscope directs the surgeon to polyps and laparoscopy enables wedge resection of benign polyps using Endo GIA staplers. Using this method, the colonoscope provides an intra-luminal view ensuring adequate excision with margins whilst the laparoscope provides intra-peritoneal access for the wedge resection. Methods: This is a case series of 12 patients with large tubulovillous adenomas, found and biopsied at colonoscopy. Under a general anaesthetic, an on table colonoscopy was performed to identify and reassess the polyp, whilst a laparoscopy was performed to excise the polyp via wedge resection, using the endoscopic view as guidance. Results: The polyp was identified and completely resected in our 12 patients. All patients were discharged on the first post-operative day. Of the polyps excised, a focus of adenocarcinoma was detected in one and an adjacent endocrine tumour was found in another patient in histology along with tubulovillous adenoma. Rest were all tubulovillous adenomas only. Conclusion: We propose that this technique should be regarded as an alternative to Right hemicolectomies and difficult endoscopic mucosal resections for large adenomas, and be regarded as a definitive and safe procedure in its own right.

“Passive-bending colonoscope”significantly improves cecal intubation in difficult cases

Colonoscopy sometimes causes pain during insertion,especially in difficult cases.Over-insufflation of air causes elongation or acute angulations of the colon,making passage of the scope difficult and causing pain.We previously reported a sedative-risk-free colonoscopy insertion technique,namely,"Water Navigation Colonoscopy".Complete air suction after water infusion not only improves the vision,but also makes water flow down to the descending colon,while the sigmoid colon collapses and shortens.While non-sedative colonoscopy can be carried out without pain in most cases,some patients do complain of pain.Most of these patients have abnormal colon morphology,and the pain is caused while negotiating the "hairpin" bends of the colon.The "hairpin" bends of the colon should be negotiated by gently pushing the full-angled colonoscope.The proximal 10-20 cm from the angulated part of the conventional colonoscope is stiff,with a wide turning radius,therefore,a conventional colonoscope cannot be negotiated through the "hairpin" bends of the colon without stretching them and causing pain.The "passive-bending colonoscope" has a flexible tip with a narrow turning radius,so that the scope can be negotiated through the "hairpin" bends of the colon with a minimum turning radius and minimal discomfort.Therefore,the intubation and pain-reducing performance of the "passive-bending colonoscope" was assessed in difficult cases.

Evaluation of the Efficacy of Transcutaneous Electrical Acupoint Stimulation during the Treatment of Painless Colonoscopy

Objective:To investigate the clinical efficacy of transcutaneous electrical acupoint stimulation combined with propofol infusion during the treatment of patients under colonoscopy.Methods:A total of 90 patients received painless colonoscopy were randomly divided into three groups:transcutaneous electrical acupoint stimulation combined with propofol group(group T),sufentanil combined with propofol group(group S)and propofol group(group P),with 30 cases in each group.The patients in group T were anesthetized with propofol after transcutaneous electrical acupoint stimulation of 30min at Hegu(LI4),Neiguan(PC6),Zusanli(ST36),Shangjuxu(ST37)and Sanyinjiao(SP6)on both sides,and the electrical stimulation lasted until the end of the operation.Group S and group P were pasted electrode slices at the same acupoint with group T,but no electrical stimulation was given.The other treatments were the same as those in group T.Group S was given sufentanil 0.1ug/kg at the beginning of anesthesia.The levels of blood pressure(MAP),heart rate(HR)and pulse oxygen saturation(SpO2)were continuously monitored at time points of entering operating room(T0),disappearance of eyelash reflex(T1),during operation(through the liver region T2)and immediately after operation(T3),and the total dosage of propofol,awakening time and incidence of adverse reactions in each group were recorded.Results:Compared with group P,the blood pressure and heart rate of the patients at T1 and T2 in group T were more stable(P<0.05),the awakening time after operation was significantly shorter(P<0.05),and the dosage of propofol was significantly lower than that in group P(P<0.05).The incidence of bradycardia,hypotension and respiratory depression decreased significantly(P<0.05).Compared with group S,the postoperative awakening time of group T was significantly shorter(P<0.05),and there was no significant difference in other indexes.Conclusion:Transcutaneous electrical acupoint stimulation is effective during the treatment of analgesia under colonoscopy.It can reduce the dosage of anesthetics,reduce the incidence of postoperative adverse reactions and shorten the awakening time of patients.