Search tips
Search criteria

Results 1-25 (1004294)

Clipboard (0)

Related Articles

1.  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 meta-analyses 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 meta-analysis 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.
PMCID: PMC3819558  PMID: 24222966
Colonoscope; Magnetic endoscope imaging; Magnetic; Standard colonoscope; Meta-analysis
2.  Effect of a proprietary intraluminal stiffening wire device on cecal intubation time and rate with used colonoscopes; a randomized, controlled trial 
BMC Research Notes  2013;6:48.
Colonoscopes are designed with balance between flexibility, required to negotiate angulations, and stiffness, required to counteract the propensity for looping in unfixed sections of the colon, which retards advancement of the instrument. Colonoscopy can be challenging with old instruments that have lost native stiffness and become less responsive to torquing.
A new intraluminal stiffening device has become available in two grades of stiffness. However, there is no published evidence of its effectiveness. This randomized, controlled trial was designed to determine the effectiveness of the stiffening wires in improving cecal intubation rate and time following routine application. A secondary analysis determines effectiveness of application only after intractable failure with the unaided colonoscope.
The colonoscope tested was an Olympus CF-100TL, approximately fifteen years old. Patients were randomly assigned to the unaided colonoscope or the standard or firm wire introduced routinely on entry into transverse colon. Each phase of colonoscopy was timed. Failure to advance the colonoscope for 5 minutes (despite usual manipulations to minimize looping) required switching to another intervention according to a prescribed methodology and the originally assigned intervention was recorded as failed.
The study was terminated after accrual of 112 participants (target sample size 480) because the colonoscope required repairs (no damage attributable to stiffening wires) which would have been uneconomical. There were no statistically significant differences between per-protocol cecal intubation rates (81.1, 71.1 and 70.3 percent respectively), a finding which persisted after multiple imputation for a virtual sample size of 480. Similarly, there were no statistically significant differences between per-protocol cecal intubation times (15, 16.2 and 13.9 minutes). However, a statistically significant improvement in cecal intubation rate (from 81.1% to 97.3%, P = 0.0313) was achieved when the wires were applied after intractable failure of the unaided colonoscope in the first intervention group.
Routine application of either stiffening wire does not improve caecal intubation rate nor time compared to the unaided colonoscope. However, application of the stiffening wires after intractable failure of the unaided colonoscope enabled a statistically significant improvement in cecal intubation rate.
Trial Registration Identifier: NCT01115010
PMCID: PMC3571927  PMID: 23379922
Used colonoscope; Old colonoscope; Colonoscope stiffness; Colonoscope stiffening device; Colonoscope stiffening wire
3.  Use of an electromagnetic colonoscope to assess maneuvers associated with cecal intubation 
BMC Gastroenterology  2009;9:24.
Safe and effective colonoscopy is aided by the use of endoscopic techniques and maneuvers (ETM) during the examination including patient repositioning, stiffening of the endoscope and abdominal pressure.
To better understand the use and value of ETM during colonoscopy by using a device that allows real-time imaging of the colonoscope insertion shaft.
The use of ETM during colonoscopy and their success was recorded. Experienced colonoscopists and endoscopy assistants used a commercially available electromagnetic (EM) transmitter and a special adult variable stiffness instrument with 12 embedded sensors to examine 46 patients. In 5 of these a special EM probe passed through the instrument channel of a standard pediatric variable stiffness colonoscope was used instead of the EM colonoscope.
Thirty-nine men and 7 women with a mean age of 64 years (range 33–90) were studied. The cecum was intubated in 93.5% (43/46). The mean time to reach the cecum was 10.6 minutes (range 3–25). ETM were used a total of 174 times in 41 of the patients to assist with cecal intubation. When ETM were required to reach the cecum, and the cecum was intubated, an average of 3.82 ETM/patient was used. While ETM were used most often when the tip of the colonoscope was in the left side of the colon (rectum 5.0%, sigmoid colon 20.7%, descending colon 5.0%, and splenic flexure 11.6%), when the instrument was in the transverse colon (14.8%), hepatic flexure (20.7%) and ascending colon (19.8%) the use of ETM was also required. When the colonoscope tip was in the transverse colon, hepatic flexure and ascending colon, ETM success rates were less (61.1%, 52.0%, and 41.7% respectively) compared to the left colon success rates (rectum 83.3%, sigmoid colon 84.0%, descending colon 100%, and splenic flexure 85.7%).
The EM colonoscope allows imaging of the insertion shaft without fluoroscopy and is a useful device for evaluating the efficacy of ETM. ETM are important tools of the colonoscopist and are used most often in the left colon where they are most effective.
PMCID: PMC2670842  PMID: 19358723
4.  Incomplete colonoscopy: Maximizing completion rates of gastroenterologists 
Cecal intubation is one of the goals of a quality colonoscopy; however, many factors increasing the risk of incomplete colonoscopy have been implicated. The implications of missed pathology and the demand on health care resources for return colonoscopies pose a conundrum to many physicians. The optimal course of action after incomplete colonoscopy is unclear.
To assess endoscopic completion rates of previously incomplete colonoscopies, the methods used to complete them and the factors that led to the previous incomplete procedure.
All patients who previously underwent incomplete colonoscopy (2005 to 2010) and were referred to St Paul’s Hospital (Vancouver, British Columbia) were evaluated. Colonoscopies were re-attempted by a single endoscopist. Patient charts were reviewed retrospectively.
A total of 90 patients (29 males) with a mean (± SD) age of 58±13.2 years were included in the analysis. Thirty patients (33%) had their initial colonoscopy performed by a gastroenterologist. Indications for initial colonoscopy included surveillance or screening (23%), abdominal pain (15%), gastrointestinal bleeding (29%), change in bowel habits or constitutional symptoms (18%), anemia (7%) and chronic diarrhea (8%). Reasons for incomplete colonoscopy included poor preparation (11%), pain or inadequate sedation (16%), tortuous colon (30%), diverticular disease (6%), obstructing mass (6%) and stricturing disease (10%). Reasons for incomplete procedures in the remaining 21% of patients were not reported by the referring physician. Eighty-seven (97%) colonoscopies were subsequently completed in a single attempt at the institution. Seventy-six (84%) colonoscopies were performed using routine manoeuvres, patient positioning and a variable-stiffness colonoscope (either standard or pediatric). A standard 160 or 180 series Olympus gastroscope (Olympus, Japan) was used in five patients (6%) to navigate through sigmoid diverticular disease; a pediatric colonoscope was used in six patients (7%) for similar reasons. Repeat colonoscopy on the remaining three patients (3%) failed: all three required surgery for strictures (two had obstructing malignant masses and one had a severe benign obstructing sigmoid diverticular stricture).
Most patients with previous incomplete colonoscopy can undergo a successful repeat colonoscopy at a tertiary care centre with instruments that are readily available to most gastroenterologists. Other modalities for evaluation of the colon should be deferred until a second attempt is made at an expert centre.
PMCID: PMC3441163  PMID: 22993727
Barium enema; Colonoscopy; CT colonography; Double-balloon enteroscopy; Incomplete colonoscopy
5.  Magnetic imaging-assisted colonoscopy vs conventional colonoscopy: A randomized controlled trial 
World Journal of Gastroenterology : WJG  2014;20(36):13178-13184.
AIM: To compare magnetic imaging-assisted colonoscopy (MIC) with conventional colonoscopy (CC).
METHODS: Magnetic imaging technology provides a computer-generated image of the shape and position of the colonoscope onto a monitor to give visual guidance to the endoscopist. It is designed to improve colonoscopy performance and tolerability for patients by enabling visualization of loop formation and endoscope position. Recently, a new version of MIC technology was developed for which there are limited data.To evaluate this latest generation of MIC among experienced rather than inexperienced or trainee endoscopists, a prospective randomized trial was performed using only gastroenterologists with therapeutic endoscopy training. Consecutive patients undergoing elective outpatient colonoscopy were randomized to MIC or CC, with patients blinded to their group assignment. Endoscopic procedural metrics and quantities of conscious sedation medications were recorded during the procedures. The procedure was classified as “usual” or “difficult” by the endoscopist at the conclusion of each case based on the need for adjunctive maneuvers to facilitate endoscope advancement. After more than one hour post-procedure, patients completed a 10 cm visual analogue pain scale to reflect the degree of discomfort experienced during their colonoscopy. The primary outcome was patient comfort expressed by the visual analogue pain score. Secondary outcomes consisted of endoscopic procedural metrics as well as a sedation score derived from standardized dose increments of the conscious sedation medications.
RESULTS: Two hundred fifty-three patients were randomized and underwent MIC or CC between September 2011 and October 2012. The groups were similar in terms of the indications for colonoscopy and patient characteristics. There were no differences in cecal intubation rates (100% vs 99%), insertion distance-to-cecum (82 cm vs 83 cm), time-to-cecum (6.5 min vs 7.2 min), or polyp detection rate (47% vs 52%) between the MIC and CC groups. The primary outcome of mean pain score (1.0 vs 0.9 out of 10, P = 0.41) did not differ between MIC and CC groups, nor did the mean sedation score (8.2 vs 8.5, P = 0.34). Within the subgroup of cases considered more challenging or difficult, time-to-cecum was significantly faster with MIC compared to CC, 10.1 min vs 13.4 min respectively (P = 0.01). Sensitivity analyses confirmed a similar pattern of overall findings when each endoscopist was considered separately, demonstrating that the mean results for the entire group were not unduly influenced by outlier results from any one endoscopist.
CONCLUSION: Although the latest version of MIC resulted in faster times-to-cecum within a subgroup of more challenging cases, overall it was no better than CC in terms of patient comfort, sedation requirements and endoscopic procedural metrics, when performed in experienced hands.
PMCID: PMC4177499  PMID: 25278714
Colonoscopy; Conscious sedation; Magnetic endoscope imaging; Pain measurement; Randomized controlled trial
6.  Endoscopic innovations to increase the adenoma detection rate during colonoscopy 
Up to a quarter of polyps and adenomas are missed during colonoscopy due to poor visualization behind folds and the inner curves of flexures, and the presence of flat lesions that are difficult to detect. These numbers may however be conservative because they mainly come from back-to-back studies performed with standard colonoscopes, which are unable to visualize the entire mucosal surface. In the past several years, new endoscopic techniques have been introduced to improve the detection of polyps and adenomas. The introduction of high definition colonoscopes and visual image enhancement technologies have been suggested to lead to better recognition of flat and small lesions, but the absolute increase in diagnostic yield seems limited. Cap assisted colonoscopy and water-exchange colonoscopy are methods to facilitate cecal intubation and increase patients comfort, but show only a marginal or no benefit on polyp and adenoma detection. Retroflexion is routinely used in the rectum for the inspection of the dentate line, but withdrawal in retroflexion in the colon is in general not recommended due to the risk of perforation. In contrast, colonoscopy with the Third-Eye Retroscope® may result in considerable lower miss rates compared to standard colonoscopy, but this technique is not practical in case of polypectomy and is more time consuming. The recently introduced Full Spectrum Endoscopy™ colonoscopes maintains the technical capabilities of standard colonoscopes and provides a much wider view of 330 degrees compared to the 170 degrees with standard colonoscopes. Remarkable lower adenoma miss rates with this new technique were recently demonstrated in the first randomized study. Nonetheless, more studies are required to determine the exact additional diagnostic yield in clinical practice. Optimizing the efficacy of colorectal cancer screening and surveillance requires high definition colonoscopes with improved virtual chromoendoscopy technology that visualize the whole colon mucosa while maintaining optimal washing, suction and therapeutic capabilities, and keeping the procedural time as low and patient discomfort as optimal as possible.
PMCID: PMC3942825  PMID: 24605019
Colonoscopy; Endoscopic innovations; Adenoma detection; Polyp detection; Gastrointestinal endoscopy
7.  A randomized, controlled trial comparing air insufflation, water immersion and water exchange during minimally sedated colonoscopy - an interim report 
Water-aided methods for colonoscopy are distinguished by timing of removal of infused water, predominantly during withdrawal (water immersion, WI), or during insertion (water exchange, WE).
In a prospective randomized controlled trial (RCT) we assessed the hypothesis that compared with air insufflation (AI), WE produces significantly greater reduction in insertion pain than WI.
The study was approval by local IRB and registered (NCT0090555). 200 patients were allocated into 3 groups by computerized randomization. AI, WI and WE were implemented as previously described. In all groups, during the insertion phase of colonoscopy, a study nurse asked the patient to report the level of pain (0=none, 10=most severe) at 2 to 3-min intervals or at any time the patient voiced discomfort. During the withdrawal phase, the pain was recorded in a similar manner. Procedural outcomes were recorded.
Demographic variables and final cecal intubation rates were comparable. Compared with AI, WI and WE both produced significantly better bowel preparation scores during colonoscope withdrawal and significantly lowered pain scores (AI 3.8±3.0, WI 2.4±2.6, WE 1.5±2.4, p<0.001) during colonoscope insertion. Compared with AI, WE produces significantly greater reduction in insertion pain than WI. The cecal intubation time was the longest in the WE group (AI vs. WI vs. WE, 8.9±7.3, 6.6±3.6 and 17.5±6.4 min, p<0.001)
Both WI and WE significantly reduced insertion pain compared with AI. Water exchange is superior to water immersion in attenuating insertion pain.
PMCID: PMC3895147  PMID: 24478927
water immersion; water exchange; air insufflation; pain; colonoscopy; intubation time; adenoma detection rate; bowel preparation score
8.  Small caliber overtube-assisted colonoscopy 
AIM: To combine the benefits of a new thin flexible scope with elimination of excessive looping through the use of an overtube.
METHODS: Three separate retrospective series. Series 1: 25 consecutive male patients undergoing unsedated colonoscopy using the new device at a Veteran’s hospital in the United States. Series 2: 75 male patients undergoing routine colonoscopy using an adult colonoscope, pediatric colonoscope, or the new device. Series 3: 35 patients who had incomplete colonoscopies using standard instruments.
RESULTS: Complete colonoscopy was achieved in all 25 patients in the unsedated series with a median cecal intubation time of 6 min and a median maximal pain score of 3 on a 0-10 scale. In the 75 routine cases, there was significantly less pain with the thin scope compared to standard adult and pediatric colonoscopes. Of the 35 patients in the previously incomplete colonoscopy series, 33 were completed with the new system.
CONCLUSION: Small caliber overtube-assisted colonoscopy is less painful than colonoscopy with standard adult and pediatric colonoscopes. Male patients could undergo unsedated colonoscopy with the new system with relatively little pain. The new device is also useful for most patients in whom colonoscopy cannot be completed with standard instruments.
PMCID: PMC4205440  PMID: 17990359
Colonoscopy; Endoscopy; Colon Cancer; Colon cancer screening
9.  Preoperative colonoscopy through the colonic stent in patients with colorectal cancer obstruction 
World Journal of Gastroenterology : WJG  2014;20(30):10570-10576.
AIM: To evaluate the feasibility of a preoperative colonoscopy through a self-expendable metallic stent (SEMS) and to identify the factors that affect complete colonoscopy.
METHODS: A total of 48 patients who had SEMS placement because of acute malignant colonic obstruction underwent preoperative colonoscopy. After effective SEMS placement, patients who showed complete resolution of radiological findings and clinical signs of acute colon obstruction underwent a standard bowel preparation. Preoperative colonoscopy was then performed using a standard colonoscope. If the passage of colonoscope was not feasible gastroscope was used. After colonoscopy, cecal intubation time, grade of bowel preparation, tumor location, stent location, presence of synchronous polyps or cancer, damage to colonoscopy and bleeding, and stent migration after colonoscopy were recorded.
RESULTS: Complete evaluation with colonoscope was possible in 30 patients (62.5%). In this group, adenoma was detected in 13 patients (43.3%). The factors that affected complete colonoscopy were also analyzed: Tumor location at an angle; stent placement at an angle; and stent expansion diameter, which affected complete colonoscopy significantly. However in multivariate analysis, stent expansion diameter was the only significant factor that affected complete colonoscopy. Complete evaluation using additional gastroscope was feasible in 42 patients (87.5%).
CONCLUSION: Preoperative colonoscopy through the colonic stent using only conventional colonoscope was unfavorable. The narrow expansion diameter of the stent may predict unfavorable outcome. In such a case, using small caliber scope should be considered and may expect successful outcome.
PMCID: PMC4130868  PMID: 25132777
Colon cancer; Stent; Preoperative colonoscopy; Complete colonoscopy
10.  A new variable stiffness colonoscope makes colonoscopy easier: a randomised controlled trial 
Gut  2000;46(6):801-805.
BACKGROUND—Colonoscopy remains technically difficult in 10-20% of procedures due to variable colonic anatomy and fixation. The ability to vary endoscope shaft flexibility may help insertion to the caecum.
METHODS—Consecutive patients attending for day case colonoscopy were randomised to examination with either the conventional Olympus CF200HL (200HL) or a new variable stiffness (VS) colonoscope. Intubation time, use of stiffening function, and patient pain scores were compared.
RESULTS—Of 100 cases, 43 were performed with the 200HL and 57 with the VS. Four incomplete examinations occurred with the 200HL (two sigmoid fixations, two benign strictures) and two with the VS (one obstructing cancer, one fixed sigmoid). Changing to the paediatric scope was successful in all but one patient from each group (obstructive lesions). Stiff mode was applied 23 times in 18 patients and was effective in 15 of these. Intubation time was quicker with the VS (median 6 minutes 32 seconds) than with the 200HL (median 10 minutes 35 seconds) (p=0.0005). Pain scores were less with the VS (median 7) than with the 200HL (median 24) (p=0.0081).
CONCLUSIONS—The variable stiffness colonoscope combines paediatric shaft characteristics with the ability to stiffen when needed. This instrument significantly reduces intubation time and patient discomfort. Further comparisons should be made with the newest colonoscopes which are less stiff.

Keywords: colonoscopy; colonoscopes; technology; pain
PMCID: PMC1756452  PMID: 10807891
11.  High Cecal Intubation Rates With a New Computer-Assisted Colonoscope: A Feasibility Study 
The acceptability of colonoscopy as a screening test is limited by several factors including patient discomfort. A new self-propelled colonoscope, the Invendo SC20 (Invendo Medical GmbH), may be helpful in reducing sedation. It consists of a sheathed endoscope contained within an “inverted sleeve,” and having an instrument channel and an electrohydraulic bendable tip; it is steered using a handheld device and propelled by a motorized drive unit. This study assessed the safety and efficacy of this new endoscope in volunteers undergoing colorectal cancer (CRC) screening.
Paid healthy volunteers aged 50–70 years and eligible for screening colonoscopy were included. Total colonoscopy using carbon dioxide insufflation or water instillation on demand was attempted, with all procedures being started without sedation. The main outcome parameters were safety and the cecal intubation rate.
A total of 61 volunteers participated (34 men and 27 women; mean age 57.5 years). The cecum was reached in 60 volunteers (cecal intubation rate of 98.4%). The median time to reach the cecum was 15 min (range 7–53.5). Sedation was given in three individuals (4.9%). On withdrawal (median time 15 min), the material for histological evaluation was obtained from 33 polyps (mean size 4.8 mm) in 23 people by biopsy forceps or snare. No device-related complications were encountered.
A new computer-assisted colonoscope, controlled using a handheld device, showed excellent cecal intubation rates during screening examinations, with sedation required in only ∼5% of screenees. Further clinical and comparative studies are warranted.
PMCID: PMC3185926  PMID: 21386833
12.  A Randomized Controlled Trial of Comparison on Time and Rate of Cecal and Termianl Ileal Intubation according to Adult-Colonoscope Length: Intermediate versus Long 
For a complete colonoscopic examination, a high intubation rate and a short intubation time have been demanded to colonoscopists, if possible. The aim of the present study was to compare these examination parameters, intubation time and rate, according to the length of colonoscope. A total of 507 healthy Korean subjects were randomly assigned into two groups: intermediate length adult-colonoscope (n=254) and long length adult-colonoscope (n=253). There were significant differences in cecal intubation time and in terminal ileal intubation rate according to the length of the colonoscope. Time-to-cecal intubation was shorter for the intermediate-scope group than for the long-scope group (234.2 ± 115.0 sec vs 280.7 ± 135.0 sec, P < 0.001). However, the success rate of terminal ileal intubation was higher in the long-scope group than in the intermediate-scope group (95.3% vs 84.3%, P < 0.001). There were no significant differences in other colonoscopic parameters between the two groups. The intermediate length adult-colonoscope decreased the time to reach the cecum, whereas the long-scope showed a success rate of terminal ileal intubation. These findings suggest that it is reasonable to prepare and use these two types of colonoscope appropriate to the needs of the patient and examination, instead of employing only one type of colonoscope.
PMCID: PMC3890483  PMID: 24431912
Colonoscopy; Intubation Time; Intubation Rate; Colonoscope Length
13.  Water exchange method for colonoscopy: learning curve of an experienced colonoscopist in a U.S. community practice setting 
Water exchange colonoscopy has been reported to reduce examination discomfort and to provide salvage cleansing in unsedated or minimally sedated patients. The prolonged insertion time and perceived difficulty of insertion associated with water exchange have been cited as a barrier to its widespread use.
To assess the feasibility of learning and using the water exchange method of colonoscopy in a U.S. community practice setting.
Quality improvement program in nonacademic community endoscopy centers.
Patients undergoing sedated diagnostic, surveillance, or screening colonoscopy.
After direct coaching by a knowledgeable trainer, an experienced colonoscopist initiated colonoscopy using the water method. Whenever >5 min elapsed without advancing the colonoscope, conversion to air insufflation was made to ensure timely completion of the examination.
Primary outcome
Water Method Intention-to-treat (ITT) cecal intubation rate (CIR).
Female patients had a significantly higher rate of past abdominal surgery and a significantly lower ITTCIR. The ITTCIR showed a progressive increase over time in both males and females to 85–90%. Mean insertion time was maintained at 9 to 10 min. The overall CIR was 99%.
Use of water exchange did not preclude cecal intubation upon conversion to usual air insufflation in sedated patients examined by an experienced colonoscopist. With practice ITTCIR increased over time in both male and female patients. Larger volumes of water exchanged were associated with higher ITTCIR and better quality scores of bowel preparation. The data suggest that learning water exchange by a busy colonoscopist in a community practice setting is feasible and outcomes conform to accepted quality standards.
PMCID: PMC3655367  PMID: 23805393
water exchange; colonoscopy; learning curve
14.  Prospective randomized controlled trial evaluating cap-assisted colonoscopy vs standard colonoscopy 
AIM: To study the significance of cap-fitted colonoscopy in improving cecal intubation time and polyp detection rate.
METHODS: This study was a prospective randomized controlled trial conducted from March 2008 to February 2009 in a tertiary referral hospital at Sydney. The primary end point was cecal intubation time and the secondary endpoint was polyp detection rate. Consecutive cases of total colonoscopy over a 1-year period were recruited. Randomization into either standard colonoscopy (SC) or cap-assisted colonoscopy (CAC) was performed after consent was obtained. For cases randomized to CAC, one of the three sizes of cap was used: D-201-15004 (with a diameter of 15.3 mm), D-201-14304 (14.6 mm) and D-201-12704 (13.0 mm). All of these caps were produced by Olympus Medical Systems, Japan. Independent predictors for faster cecal time and better polyp detection rate were also determined from this study.
RESULTS: There were 200 cases in each group. There was no significant difference in terms of demographic characteristics between the two groups. CAC, when compared to the SC group, had no significant difference in terms of cecal intubation rate (96.0% vs 97.0%, P = 0.40) and time (9.94 ± 7.05 min vs 10.34 ± 6.82 min, P = 0.21), or polyp detection rate (32.8% vs 31.3%, P = 0.75). On the subgroup analysis, there was no significant difference in terms of cecal intubation time by trainees (88.1% vs 84.8%, P = 0.40), ileal intubation rate (82.5% vs 79.0%, P = 0.38) or total colonoscopy time (23.24 ± 13.95 min vs 22.56 ± 9.94 min, P = 0.88). On multivariate analysis, the independent determinants of faster cecal time were consultant-performed procedures (P < 0.001), male patients (P < 0.001), non-usage of hyoscine (P < 0.001) and better bowel preparation (P = 0.01). The determinants of better polyp detection rate were older age (P < 0.001), no history of previous abdominal surgery (P = 0.04), patients not having esophagogastroduodenoscopy in the same setting (P = 0.003), trainee-performed procedures (P = 0.01), usage of hyoscine (P = 0.01) and procedures performed for polyp follow-up (P = 0.01). The limitations of the study were that it was a single-center experience, no blinding was possible, and there were a large number of endoscopists.
CONCLUSION: CAC did not significantly different from SC in term of cecal intubation time and polyp detection rate.
PMCID: PMC2923764  PMID: 20712051
Cap; Hood; Cecum; Colonoscopy; Cecal intubation; Colonic polyps
15.  Predictive factors affecting cecal intubation failure in colonoscopy trainees 
Successful cecal intubation (SCI) is not only a quality indicator but also an important marker in a colonoscopy trainee’s progress. We conducted this study to determine factors predicting SCI in colonoscopy trainees, and to compare these factors before and after trainees achieve technical competence.
Design of this study was a cross-sectional studies of two time series design for one year at a single center. From March 2011 to February 2012, a total 2,050 subjects who underwent colonoscopy by four first-year gastrointestinal fellows were enrolled at Christian hospital, Wonju, Republic of Korea. Four gastrointestinal fellows have filled out the colonoscopic documentation. Main outcome measurement was predictive factors affecting cecal intubation failure and learning curves.
Colonoscopy was successfully completed to the cecum in 1,720 patients (83.9%). Success rates gradually increased as trainees performed more colonoscopies: the rate of SCI was 62% in the first 50 cases, and grew to 93% by the 250th case. Logistic regression analysis of factors affecting cecal intubation failure showed that female gender, low BMI (BMI < 18.5 kg/m2), poor bowel preparation, and past history of stomach surgery were more often associated with cecal intubation failure, particularly before the trainees achieved technical competence.
Several patient characteristics were identified that may predict difficulty of cecal intubation in colonoscopy trainees. Particularly, low BMI, inadequate bowel cleansing, and previous stomach operation were predictors of cecal intubation failure before the trainees have reached technical competency. The results could be informative so that trainees enhance the success rate regarding better colonoscopy training programs.
PMCID: PMC3560110  PMID: 23331720
16.  Retrospective analysis showing the water method increased adenoma detection rate — a hypothesis generating observation 
A water method developed to attenuate discomfort during colonoscopy enhanced cecal intubation in unsedated patients. Serendipitously a numerically increased adenoma detection rate (ADR) was noted.
To explore databases of sedated patients examined by the air and water methods to identify hypothesis-generating findings. Design: Retrospective analysis. Setting: VA endoscopy center. Patients: creening colonoscopy. Interventions: From 1/2000–6/2006 the air method was used - judicious air insufflation to permit visualization of the lumen to aid colonoscope insertion and water spray for washing mucosal surfaces. From 6/2006–11/2009 the water method was adopted - warm water infusion in lieu of air insufflation and suction removal of residual air to aid colonoscope insertion. During colonoscope withdrawal adequate air was insufflated to distend the colonic lumen for inspection, biopsy and polypectomy in a similar fashion in both periods. Main outcome measurements: ADR.
The air (n=683) vs. water (n=495) method comparisons revealed significant differences in overall ADR 26.8% (183 of 683) vs. 34.9% (173 of 495) and ADR of adenomas >9 mm, 7.2% vs. 13.7%, respectively (both P<0.05, Fisher's exact test). Limitations: Non-randomized data susceptible to bias by unmeasured parameters unrelated to the methods.
Confirmation of the serendipitous observation of an impact of the water method on ADR provides impetus to call for randomized controlled trials to test hypotheses related to the water method as an approach to improving adenoma detection. Because of recent concerns over missed lesions during colonoscopy, the provocative hypothesis-generating observations warrant presentation.
PMCID: PMC3109466  PMID: 21686105
colorectal cancer screening; optical colonoscopy; water method; adenoma detection
17.  Benefit of “transparent soft-short-hood on the scope” for colonoscopy among experienced gastroenterologists and gastroenterologist trainee: a randomized, controlled trial 
Surgical Endoscopy  2011;26(4):1041-1046.
The attachment of a transparent hood to the colonoscope tip has been reported to offer some benefits, such as enabling the endoscopist to perform the colonoscopy more easily and to save time. However, there have been no randomized, controlled trials concerning these benefits, nor have any reports been published regarding the use of hoods for the purpose of training colonoscopists. Therefore, we conducted this study to evaluate the possible benefits of the transparent soft short hood when used by both experienced and trainee endoscopist groups.
This randomized, controlled trial to assess the results of using a transparent soft short hood attached to the tip of the colonoscope was undertaken by two groups of investigators: experienced endoscopists and gastroenterologist trainees. The cecal and ileal intubation times, as well as the doses of sedative medication required, were analyzed.
A total of 112 patients, 65 of whom were female, underwent colonoscopy by 2 endoscopists and 5 gastroenterologist trainees. Colonoscopy was complete in 100% of the patients. The study showed significant shortening of the cecal intubation time when using the soft short hood, in both the endoscopist and gastroenterologist trainee groups (6.8/4.61 min, P = 0.006; and 9.36/7.36 min, P = 0.03). The ileal intubation time had a trend to be significantly less when using the transparent hood in the trainee group (126.4/52.9 s), although this was not statistically significant (P = 0.08). The average dose of propofol, when using the transparent hood, was significantly lower in the endoscopist group (180/120 mg, P = 0.001). No significant complications occurred in the hood or non-hood groups.
The transparent soft short hood shortened the cecal intubation time in both the experienced endoscopist and gastroenterologist trainee groups, as well as reducing the dose of sedative medication required in the experienced endoscopist group. Interestingly, it also reduced the trainee ileal intubation time. The attachment of this type of hood enabled both the experienced endoscopists and gastroenterological trainees to perform colonoscopy more quickly and easily, without any complications.
PMCID: PMC3310994  PMID: 22042588
Transparent hood; Colonoscopy; Cecal intubation time; Ileal intubation time
18.  Ileocecal valve dysfunction in small intestinal bacterial overgrowth: A pilot study 
AIM: To explore whether patients with a defective ileocecal valve (ICV)/cecal distension reflex have small intestinal bacterial overgrowth.
METHODS: Using a colonoscope, under conscious sedation, the ICV was intubated and the colonoscope was placed within the terminal ileum (TI). A manometry catheter with 4 pressure channels, spaced 1 cm apart, was passed through the biopsy channel of the colonoscope into the TI. The colonoscope was slowly withdrawn from the TI while the manometry catheter was advanced. The catheter was placed across the ICV so that at least one pressure port was within the TI, ICV and the cecum respectively. Pressures were continuously measured during air insufflation into the cecum, under direct endoscopic visualization, in 19 volunteers. Air was insufflated to a maximum of 40 mmHg to prevent barotrauma. All subjects underwent lactulose breath testing one month after the colonoscopy. The results of the breath tests were compared with the results of the pressures within the ICV during air insufflation.
RESULTS: Nineteen subjects underwent colonoscopy with measurements of the ICV pressures after intubation of the ICV with a colonoscope. Initial baseline readings showed no statistical difference in the pressures of the TI and ICV, between subjects with positive lactulose breath tests and normal lactulose breath tests. The average peak ICV pressure during air insufflation into the cecum in subjects with normal lactulose breath tests was significantly higher than cecal pressures during air insufflation (49.33 ± 7.99 mmHg vs 16.40 ± 2.14 mmHg, P = 0.0011). The average percentage difference of the area under the pressure curve of the ICV from the cecum during air insufflations in subjects with normal lactulose breath tests was significantly higher (280.72% ± 43.29% vs 100% ± 0%, P = 0.0006). The average peak ICV pressure during air insufflation into the cecum in subjects with positive lactulose breath tests was not significantly different than cecal pressures during air insufflation 21.23 ± 3.52 mmHg vs 16.10 ± 3.39 mmHg. The average percentage difference of the area under the pressure curve of the ICV from the cecum during air insufflation was not significantly different 101.08% ± 7.96% vs 100% ± 0%. The total symptom score for subjects with normal lactulose breath tests and subjects with positive lactulose breath tests was not statistically different (13.30 ± 4.09 vs 24.14 ± 6.58). The ICV peak pressures during air insufflations were significantly higher in subjects with normal lactulose breath tests than in subjects with positive lactulose breath tests (P = 0.005). The average percent difference of the area under the pressure curve in the ICV from cecum was significantly higher in subjects with normal lactulose breath tests than in subjects with positive lactulose breath tests (P = 0.0012). Individuals with positive lactulose breath tests demonstrated symptom scores which were significantly higher for the following symptoms: not able to finish normal sized meal, feeling excessively full after meals, loss of appetite and bloating.
CONCLUSION: Compared to normal, subjects with a positive lactulose breath test have a defective ICV cecal distension reflex. These subjects also more commonly have higher symptom scores.
PMCID: PMC3520169  PMID: 23239918
Ileocecal valve; Ileocecal sphincter; Cecum; Reflex; Lactulose breath test; Small bowel bacterial overgrowth
19.  Point-of-care, peer-comparator colonoscopy practice audit: The Canadian Association of Gastroenterology Quality Program – Endoscopy 
Point-of-care practice audits allow documentation of procedural outcomes to support quality improvement in endoscopic practice.
To evaluate a colonoscopists’ practice audit tool that provides point-of-care data collection and peer-comparator feedback.
A prospective, observational colonoscopy practice audit was conducted in academic and community endoscopy units for unselected patients undergoing colonoscopy. Anonymized colonoscopist, patient and practice data were collected using touchscreen smart-phones with automated data upload for data analysis and review by participants. The main outcome measures were the following colonoscopy quality indicators: colonoscope insertion and withdrawal times, bowel preparation quality, sedation, immediate complications and polypectomy, and biopsy rates.
Over a span of 16 months, 62 endoscopists reported on 1279 colonoscopy procedures. The mean cecal intubation rate was 94.9% (10th centile 84.2%). The mean withdrawal time was 8.8 min and, for nonpolypectomy colonoscopies, 41.9% of colonoscopists reported a mean withdrawal time of less than 6 min. Polypectomy was performed in 37% of colonoscopies. Independent predictors of polypectomy included the following: endoscopy unit type, patient age, interval since previous colonoscopy, bowel preparation quality, stable inflammatory bowel disease, previous colon polyps and withdrawal time. Withdrawal times of less than 6 min were associated with lower polyp removal rates (mean difference −11.3% [95% CI −2.8% to −19.9%]; P=0.01).
Cecal intubation rates exceeded 90% and polypectomy rates exceeded 30%, but withdrawal times were frequently shorter than recommended. There are marked practice variations consistent with previous observations.
Real-time, point-of-care practice audits with prompt, confidential access to outcome data provide a basis for targeted educational programs to improve quality in colonoscopy practice.
PMCID: PMC3027329  PMID: 21258663
Colonoscopy; Health care; Practice audit; Quality assurance; Quality indicators
20.  The water method colonoscopy in routine unsedated colonoscopy examinations: a randomized controlled trial in diagnostic cases in Indonesian patients 
A proof-of-principle randomized controlled trial (RCT) by a US colonoscopist with limited experience in scheduled unsedated colonoscopy showed that water exchange produced significant patient-centered benefits at the expense of prolonged procedural times.
To determine if a colonoscopist experienced in scheduled unsedated colonoscopy in Indonesia can reproduce the beneficial effects without negative procedural outcomes.
Prospective, RCT (NCT01341847)
Single center, in and outpatients of Sardjito General Hospital
110 consecutive symptomatic patients meeting inclusion criteria
In the water-aided (study) method the air pump was turned off; water at room temperature was infused to aid colonoscope advancement. Residual colonic air was bypassed. Except for cleansing the infused water was suctioned during withdrawal. In the air (control) method air insufflation was used during insertion.
Main Outcome Measurements
The discomfort during insertion (primary outcome) was scored by the patient (visual analog scale: 0=none, 10=most severe) shortly after completion of colonoscopy. Secondary outcomes included patient and procedural measures.
57 and 53 patients were randomized to the control or study method, respectively. Air vs. water-aided method comparisons revealed: mean discomfort score (±SD), 6.4±2.4 vs. 4.1±2.6 (p<0.001, t-test); willingness to repeat, 62.7% vs. 83.7% (p=0.024, Fisher's exact test); cecal intubation time 12.9±7.1 vs.11.9±5.5 minutes (p=0.38); cecal intubation rate, 89.5% vs. 92.4% (p=0.74). Discomfort score was not correlated with duration of examination.
Unblinded study
Experience in scheduled unsedated colonoscopy permitted replication of patient-centered benefits of water-aided method in Indonesian patients without adverse impacts on colonoscopist-centered procedural outcomes.
PMCID: PMC3791534  PMID: 24147221
colonoscopy; unsedated; air method; water-aided method; discomfort score
21.  Maximizing the general success of cecal intubation during propofol sedation in a multi-endoscopist academic centre 
BMC Gastroenterology  2010;10:123.
Achieving the target of 95% colonoscopy completion rate at centres conducting colorectal screening programs is an important issue. Large centres and teaching hospitals employing endoscopists with different levels of training and expertise risk achieving worse results. Deep sedation with propofol in routine colonoscopy could maximize the results of cecal intubation.
The present study on the experience of a single centre focused on estimating the overall completion rate of colonoscopies performed under routine propofol sedation at a large teaching hospital with many operators involved, and on assessing the factors that influence the success rate of the procedure and how to improve this performance, analyzing the aspects relating to using of deep sedation. Twenty-one endoscopists, classified by their level of specialization in colonoscopic practice, performed 1381 colonoscopies under deep sedation. All actions needed for the anaesthesiologist to restore adequate oxygenation or hemodynamics, even for transient changes, were recorded.
The "crude" overall completion rate was 93.3%. This finding shows that with routine deep sedation, the colonoscopy completion rate nears, but still does not reach, the target performance for colonoscopic screening programs, at centers where colonoscopists of difference experience are employed in such programs.
Factors interfering with cecal intubation were: inadequate colon cleansing, endoscopists' expertise in colonoscopic practice, patients' body weight under 60 kg or age over 71 years, and the need for active intervention by the anaesthesiologist. The most favourable situation - a patient less than 71 years old with a body weight over 60 kg, an adequate bowel preparation, a "highly experienced specialist" performing the test, and no need for active anaesthesiological intervention during the procedure - coincided with a 98.8% probability of the colonoscopy being completed.
With routine deep sedation, the colonoscopy completion rate nears the target performance for colonoscopic screening programs, at centers where colonoscopists of difference experience are employed in such programs. Organizing the daily workload to prevent negative factors affecting the success rate from occurring in combination may enable up to 85% of incomplete procedures to be converted into successful colonoscopies.
PMCID: PMC2975653  PMID: 20961451
22.  A randomized double blind crossover placebo-controlled clinical trial to assess the effects of a mouthwash containing chlorine dioxide on oral malodor 
Trials  2008;9:71.
Previous research has shown the oxidizing properties and microbiological efficacies of chlorine dioxide (ClO2), however, its clinical efficacies on oral malodor have been evaluated only with organoleptic measurements (OM) or sulphide monitors. No clinical studies have investigated the inhibitory effects of ClO2 on volatile sulfur compounds (VSCs) using gas chromatography (GC). The aim of this study was to assess the inhibitory effects of a mouthwash containing ClO2 on morning oral malodor using OM and GC.
A randomized, double blind, crossover, placebo-controlled clinical trial was conducted among 15 healthy male volunteers, who were divided into 2 groups. In the first test phase, the group 1 subjects (N = 8) were instructed to rinse with the experimental mouthwash containing ClO2, and those in group 2 (N = 7) to rinse with the placebo mouthwash without ClO2. In the second test, phase after a one week washout period, each group used the opposite mouthwash.
Oral malodor was evaluated before rinsing, right after rinsing and every 30 minutes up to 4 hours with OM, and concentrations of hydrogen sulfide (H2S), methyl mercaptan (CH3SH) and dimethyl sulfide ((CH3)2S), the main VSCs of human oral malodor, were evaluated with GC.
The baseline oral condition in the subjects in the 2 groups did not differ significantly. The mouthwash containing ClO2 improved morning bad breath according to OM and reduced concentrations of H2S, CH3SH and (CH3)2S according to GC up to 4 hours after rinsing. OM scores with ClO2 were significantly lower than those without ClO2 at all examination times. Significant reductions in the concentrations of the three kinds of VSCs measured by GC were also evident at all examination times. The concentrations of the three gases with ClO2 were significantly lower than those without ClO2 at most examination times.
In this explorative study, ClO2 mouthwash was effective at reducing morning malodor for 4 hours when used by healthy subjects.
Trial registration NCT00655772
PMCID: PMC2637235  PMID: 19068114
23.  Cap assisted colonoscopy for the detection of serrated polyps: a post-hoc analysis 
BMC Gastroenterology  2015;15:11.
Colonoscopy offers limited protection against right-sided colon cancer, a significant proportion of which arise from the serrated pathway of carcinogenesis. The aim of this study was to compare cap-assisted colonoscopy and standard high-definition white light colonoscopy regarding serrated polyps’ detection.
Post hoc analysis was performed of a previously conducted randomized controlled trial comparing standard and cap-assisted colonoscopy for adenoma detection. Randomization was stratified based on the indication of colonoscopy and all procedures were performed by three experienced endoscopists. Following cecal intubation, the colonic mucosa was carefully inspected during withdrawal of colonoscope and all polyps detected were documented for their size, location, morphology and then removed and sent for histopathology. Detection rates of significant serrated polyps between both arms were compared using the Fisher’s exact test and Wilcoxon Rank Sum test.
427 patients were enrolled (7 exclusions, 210 completed study in each arm, mean age of 61 years, 95% male, 75% Caucasian, 67% screening colonoscopies). There were no significant differences in baseline characteristics between both groups. Cap-assisted colonoscopy detected a significantly higher proportion of subjects with significant serrated polyps as well as a higher total number of significant serrated polyps compared to standard colonoscopy (12.8% vs. 6.6%, p =0.047 and 40 vs. 20,p = 0.03 respectively).
In this post-hoc analysis, Cap-assisted colonoscopy is a safe technique that offers a higher detection rate of significant serrated polyps when compared to standard colonoscopy. If confirmed in future trials, this simple technique has the potential to improve protection against interval colon cancers.
PMCID: PMC4334853  PMID: 25652842
Colorectal cancer; Serrated polyps; Cap-assisted colonoscopy; Interval colon cancer
24.  A prospective intervention study of colonoscopy reporting among patients screened or surveilled for colorectal neoplasia 
The impact of modifying electronic colonoscopy reporting software for improving adherence to guidelines regarding quality standards documentation remains poorly characterized.
Consecutive colonoscopy reports of patients undergoing screening or surveillance for colorectal neoplasia were reviewed. Following a pre-intervention quality audit conducted in 2009, some modifications were made to the reporting software (Endoworks, Olympus Corporation, USA), including changes to field navigation, drop-down menus and visual cues, to optimize all compulsory items identified by existing guidelines in the report-generating template. Results from both audits were compared. Independent validation of 10% of all data was completed.
In 250 patient reports (mean [± SD] age 61.7±10.2 years, 51.2% female, February to May 2011) of five endoscopists (mean 11.6±7.8 years in practice), procedural indication was always present, as was informed consent. Seventy-six per cent of patients had undergone previous colonoscopy, 41% provided a previous colonoscopy date, with details on past polyp removal in 42.9%. Most procedural indicators were recorded (examination date 100%, medications given 100%, difficulty level 96.4%, preparation quality 100%). All reports noted extent of visualization (cecal intubation in 97.6%, photo documentation in 96.8%). Total procedural time was recorded in 8.2% and withdrawal time in 44%. Polyps were reported in 112 patients (44.8%), with polyp size (5.01±4.42 mm) reported in 95.5%, morphology in 88.4% and anatomical location in all. The method of polyp removal was missing in 2.7% of reports. Significant improvements were noted in the documentation of withdrawal and total time, cecal landmarks, type of bowel preparation, completeness of removal, morphology and method of polyp removal, and photo documentation compared with the 2009 audit.
These results illustrate the value of targeted modifications to an electronic colonoscopic reporting system in significantly enhancing the quality of reporting.
PMCID: PMC3472912  PMID: 23061065
Audit; Colonoscopy; Colorectal cancer; Endoscopy; Quality; Reporting; Surveillance
25.  Diagnostic and therapeutic applications of water-immersion colonoscopy 
Colonoscopy techniques combining or replacing air insufflation with water infusion are becoming increasingly popular. They were originally designed to reduce colonic spasms, facilitate cecal intubation, and lower patient discomfort and the need for sedation. These maneuvers straighten the rectosigmoid colon and enable the colonoscope to be inserted deeply without causing looping of the colon. Water-immersion colonoscopy minimizes colonic distension and improves visibility by introducing a small amount of water. In addition, since pain during colonoscopy indicates risk of bowel perforation and sedation masks this important warning, this method has the potential to be the favored insertion technique because it promotes patient safety without sedation. Recently, this water-immersion method has not only been used for colonoscope insertion, but has also been applied to therapy for sigmoid volvulus, removal of lesions, lower gastrointestinal bleeding, and therapeutic diagnosis of abnormal bowel morphology and irritable bowel syndrome. Although a larger sample size and prospective head-to-head-designed studies will be needed, this review focuses on the usefulness of water-immersion colonoscopy for diagnostic and therapeutic applications.
PMCID: PMC4458756  PMID: 26074684
Colonoscopy; Water immersion; Water exchange; Underwater; Unsedated; Sigmoid volvulus; Detorsion; Polypectomy; Gastrointestinal bleeding; Irritable bowel syndrome

Results 1-25 (1004294)