Improved colonoscopy success rate with a distally attached mucosectomy cap

Efficacy of combination colonoscopy using modified cap-assisted and water-exchange colonoscopy with prone position for detection of colorectal adenomas

The efficacy of cap-assisted and water-exchange colonoscopy, individually or in combination for adenoma detection is well documented. Moreover, prone positioning colonoscopy may also improve adenoma detection by decreasing loop formation. However, the efficacy of triple-combination colonoscopy using the above methods for adenoma detection is unclear. This study aimed to compare the effectiveness of combining modified cap-assisted and water-exchange colonoscopy with prone position (CWP) and conventional colonoscopy (CC) for adenoma detection. A total of 746 patients who underwent either CWP or CC, performed by 2 board-certified gastroenterologists between December 2019 and March 2020, were investigated retrospectively. Cap-assisted colonoscopy was modified using hooking and dragging maneuver. We evaluated the polyp detection rate (PDR), adenoma detection rate (ADR), and the mean number of adenomas detected per procedure (MAP). There was no significant difference in sex, age, the indication of colonoscopy and quality of bowel preparation between the 2 groups. PDR, ADR, and proximal colon MAP were significantly higher in the CWP group than in the CC group (PDR: 84.9% vs 59.8%, P < .01; ADR: 70.1%, vs 49.2%, P < .01; proximal colon MAP: 1.24 vs 0.55, P < .01). CWP is more effective than CC for PDR, ADR, and proximal colon MAP. Although it may facilitate adenoma detection, further studies assessing the synergistic or complementary effects of combining these methods are needed.

Indications and outcomes of endoscopic resection for non-pedunculated colorectal lesions: A narrative review

In the last years, endoscopic techniques gained a crucial role in the treatment of colorectal flat lesions. At the same time, the importance of a reliable assessment of such lesions to predict the malignancy and the depth of invasion of the colonic wall emerged. The current unsolved dilemma about the endoscopic excision techniques concerns the necessity of a reliable submucosal invasive cancer assessment system that can stratify the risk of the post-procedural need for surgery. Accordingly, this narrative literature review aims to compare the available diagnostic strategies in predicting malignancy and to give a guide about the best techniques to employ. We performed a literature search using electronic databases (MEDLINE/PubMed, EMBASE, and Cochrane Library). We collected all articles about endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) registering the outcomes. Moreover, we analyzed all meta-analyses comparing EMR vs ESD outcomes for colorectal sessile or non-polypoid lesions of any size, preoperatively estimated as non-invasive. Seven meta-analysis studies, mainly Eastern, were included in the analysis comparing 124 studies and overall 22954 patients who underwent EMR and ESD procedures. Of these, eighty-two were retrospective, twenty-four perspective, nine case-control, and six cohorts, while three were randomized clinical trials. A total of 18118 EMR and 10379 ESD were completed for a whole of 28497 colorectal sessile or non-polypoid lesions > 5-10 mm in size. In conclusion, it is crucial to enhance the preoperative diagnostic workup, especially in deciding the most suitable endoscopic method for radical resection of flat colorectal lesions at risk of underlying malignancy. Additionally, the ESD necessitates further improvement because of the excessively time-consuming as well as the intraprocedural technical hindrances and related complications. We found a higher rate of en bloc resections and R0 for ESD than EMR for non-pedunculated colorectal lesions. Nevertheless, despite the lower local recurrence rates, ESD had greater perforation rates and needed lengthier procedural times. The prevailing risk for additional surgery in ESD rather than EMR for complications or oncologic reasons is still uncertain.

Performance of radiographic imaging after incomplete colonoscopy for nonmalignant causes in clinical practice

BACKGROUND AND AIMS

CT colonography (CTC) or barium enema are commonly ordered to complete colorectal imaging after an incomplete colonoscopy. We evaluated the sensitivity of radiographic studies performed for this purpose in clinical practice outside clinical trials.

METHODS

Adult patients referred to an expert endoscopist for incomplete colonoscopy because of a redundant colon or a difficult sigmoid and who underwent previous radiographic imaging between July 2001 and July 2019 were identified. None of the patients had a malignant obstruction as the cause of incomplete colonoscopy. Data on polyp size, location, and pathology were obtained from colonoscopy and radiology reports. Polyps identified on imaging and colonoscopy were matched based on polyp size and location.

RESULTS

Among 769 patients referred for incomplete colonoscopy, we identified 65 with a radiographic examination performed within 36 months of colonoscopy at our center. Per-patient sensitivity for CTC was suboptimal (70%) and was very low for barium enema (26.7%). Per-polyp sensitivity for both CTC and barium enema was poor (23.8% and 7.6%). Quality of the examination did not seem to affect procedure sensitivity.

CONCLUSIONS

Radiographic imaging after incomplete colonoscopy for reasons other than malignant obstruction had poor sensitivity for polyps. Patients with incomplete colonoscopies should be considered for repeat colonoscopy by an expert.

When Experts Fail: Use of a Short Turning Radius Colonoscope Facilitates Successful Completion of Colonoscopy in Patients with Bowel Fixity

BACKGROUND

Rates of incomplete colonoscopy in non-expert settings range up to 13%. Expert colonoscopists can complete ~ 95% colonoscopies when other endoscopists fail; however, a small number remain incomplete even in expert hands, typically due to bowel fixity.

AIMS

Pentax Retroview™ (EC-3490TLi) is a new slim colonoscope with a short turning radius (STR) and greater tip deflection (210°), which allows easy maneuverability across sharply angulated/fixed colonic bends. We evaluated the utility of this colonoscope for completing colonoscopies that fail even in the hands of expert colonoscopists.

METHODS

Retrospective chart review was performed, and main outcomes measured included cecal intubation rate, lesions detected, dosage of sedation used, and complications.

RESULTS

Using the STR colonoscope, complete colonoscopy to the cecum was possible in 34/37 patients (91.9%). No loss of lumen/blind advancement was necessary in any of the procedures. No adverse events occurred. Among the completed colonoscopies, 6/34 (17.6%) patients had adenomas, all proximal to the site of prior failure, including one advanced adenoma. All failures (n = 3, 8.1%) had a history of cancer surgeries, with peritoneal carcinomatosis/extensively fixed/frozen bowel (two patients) and an additional diverticular stricture with colo-vesical fistula (one patient).

CONCLUSION

STR colonoscope facilitates completion of a high proportion (91.9%) of colonoscopies that previously failed in expert hands. Its STR allows easy maneuverability across segments of sharp angulation with bowel fixity without need for blind advancement. The use of this colonoscope led to the detection of adenomas in 17.6% of patients, all proximal to the site of prior failed colonoscopy.

Use of a Transparent Cap Increases the Diagnostic Yield in Antegrade Single-Balloon Enteroscopy for Obscure GI Bleed

BACKGROUND AND AIMS

Single-balloon enteroscopy (SBE) is utilized in the evaluation of obscure gastrointestinal bleeding, but 40-50% of these patients experience continued GI blood loss, in part due to missed lesions. The utilization of a transparent cap attached to the end of the endoscope can improve mucosal visualization in other endoscopic applications, but has not yet been evaluated in SBE. The aim of this study was to evaluate the impact of a cap on the diagnostic yield of SBE.

METHODS

Consecutive adult patients scheduled for anterograde SBE for the evaluation of obscure GI bleeding were screened for inclusion from 2014 to 2017. Patients were randomized to SBE with or without a transparent cap. The primary outcome was the proportion of enteroscopies in which a P2 lesion (high potential for bleeding) was identified.

RESULTS

A total of 90 patients (65.7 ± 12.7 years old, 47.7% female) were analyzed. There were significantly more P2 arteriovenous malformations identified in the cap group (14.8% vs. 0%, p = 0.02). Additionally, the use of a cap was associated with a significantly greater depth of small bowel insertion (191.9 cm vs. 156.2 cm, p = 0.01). There was one perforation in the group without a cap, successfully treated with clip placement, and no adverse events in the cap group.

CONCLUSIONS

The use of a transparent cap during SBE performed for the evaluation of obscure gastrointestinal bleeding may be an important, safe augmentation to standard SBE techniques.

Cap-assisted endoscopy: Do we have enough evidence?

So, is there enough evidence to incorporate CC in clinical practice? If we interpret the literature and the meta-analysis by Nutalapati et al., the answer for the clinically-focused endoscopist, with regard to adenoma detection rate (ADR), at present, may be "no". Significant differences do not necessarily imply clinical benefits and translation into clinical practice. The answer for the improvement of cecal intubation frequency and intubation time by the cap depends on the focus of training commitment, because these effects of the cap may be beneficial, especially for unexperienced endoscopists. It is obvious that further studies are needed. In this line, it is interesting to know, that in a recent meta-analysis of prospective studies, the length of the transparent cap had opposite effects on investigation time and polyp detection rate. Whereas, the anal to cecal time was significantly shortened by a cap length of > 7 mm and a polyp detection rate was significantly improved by a cap length of < 4 mm.

PillCamColon2 after incomplete colonoscopy - A prospective multicenter study

AIM

To evaluate the ability of PillCamColon2 to visualize colonic segments missed by incomplete optical colonoscopy (OC) and to assess the diagnostic yield.

METHODS

This prospective multicentre study included 81 patients from nine centres who underwent second-generation colon capsule endoscopy (CCE) following incomplete OC performed by an experienced gastroenterologist (> 1000 colonoscopies). Patients with stenosis were excluded. According to patient preferences, CCE was performed the following day (protocol A) after staying on clear liquids and 0.75 L Moviprep in the morning or within 30 d after new split-dose Moviprep (protocol B). Boosts consisted of 0.75 L and 0.25 L Moviprep, and phospho-soda was given as a rescue if the capsule was not excreted after seven hours.

RESULTS

Seventy-four patients were analysed (51% of them in group A; 49% in group B). Bowel cleansing was adequate in 67% of cases, and CCE could visualize colonic segments missed by incomplete colonoscopy in 90% of patients under protocol A and 97% of patients under protocol B (P = 0.35, n.s.). Significant polyps including adenocarcinoma were detected in 24% of cases. Detection rates for all polyps and significant polyps per patient were similar in both protocols. Polyps were found predominantly in the right colon (86%) in segments that were not reached by OC. Extracolonic findings - such as reflux esophagitis, suspected Barrett esophagus, upper GI-bleeding, gastric polyps, gastric erosions and angiectasia - were detected in eight patients. PillCamColon2 capsule was retained in the ileum of one patient (1.4%) without symptoms and removed during an uneventful resection for unknown Crohn’s disease that was diagnosed as the cause of anemia, which was the indication for colonoscopy. CCE was well tolerated. One patient suffered from self-limiting vomiting after consuming the phospho-soda.

CONCLUSION

Second-generation CCE using a low-volume preparation is useful after incomplete OC, and it allows for the detection of additional relevant findings, but cleansing efficiency could be improved.

The efficacy of cap-assisted colonoscopy performed by a single endoscopist in patients after colorectal resection

BACKGROUND

The use of a transparent cap is regarded as a simple method to obtain better outcomes compared with standard colonoscopy. In this study, we investigated whether cap-assisted colonoscopy can improve the quality of procedure-related outcomes in patients with a history of colorectal resection.

METHODS

This study was designed as a prospective, randomized, controlled trial conducted at a single tertiary center by a single endoscopist (Kang J.). A total 183 patients after colorectal resection due to primary colorectal cancer were enrolled and 1:1 randomized to undergo either cap-assisted colonoscopy (CAP group) or standard colonoscopy (non-CAP group). The primary endpoint was the comparison of cecal intubation time between the 2 groups.

RESULTS

The mean cecal intubation time of the CAP group (n = 89) was significantly shorter than that of the non-CAP group (n = 89) (538 seconds vs 677 seconds, P = 0.024). In the CAP group, the endoscopist performed faster intubation than average more often compared with the non-CAP group (71.9% vs 57.3%). In regard to moving average curve, the CAP group showed a gentle slope during the learning period, while the non-CAP group showed a steep decrease.

CONCLUSION

The cap-assisted colonoscopy could reduce cecal intubation time and achieve more frequent faster intubation compared with standard colonoscopy in patients after colorectal resection.

Novel endocuff-assisted colonoscopy significantly increases the polyp detection rate: a randomized controlled trial

GOALS AND BACKGROUND

Screening colonoscopy for colorectal cancer has proven to reduce mortality rates. Recently the Endocuff (EC), an attachment to the distal tip of the colonoscope, was introduced. The aim of our study was to compare EC-assisted colonoscopies with standard colonoscopies for the detection of colonic polyps.

STUDY

This study is a randomized prospective 2-center trial. The study was conducted at 2 tertiary care centers.

PARTICIPANTS

A total of 498 patients [249 males; median age 67 y; interquartile range (IQR), 56-75 y] for colon adenoma screening purposes were included. All patients underwent standard colonoscopy with or without the use of EC. Overall polyp detection rate, the number of colonic polyps, and the polyp distribution in the colon were measured. Difference in recognition of polyps with or without the use of EC was assessed. Statistical analysis was applied.

RESULTS

In the EC group, the number of polyps detected per patient was 63% higher [2.00 (IQR, 1.00-4.00) vs. 1.00 (IQR, 1.00-2.25), P<0.0001]. The polyp detection rate in patients increased by 14% with the use of EC (56% vs. 42%, P=0.001). For polyp detection, superiority by use of EC could be observed in the sigmoid (P=0.001) and cecum (P=0.002) for polyps <1 cm in diameter. In the EC group, the number of adenomas detected per patient significantly increased by 86% (P=0.002). No major complications occurred in both groups.

CONCLUSIONS

The use of the EC is feasible and safe with significantly higher polyp detection rates, especially for those located in the sigmoid region. The cuff system has the potential to improve the accuracy of screening colonoscopies.

Difficult colonoscopy score identifies the difficult patients undergoing unsedated colonoscopy

Background

Many factors have been found to affect the difficulty of colonoscope insertion, such as age, gender, body mass index (BMI), history of abdominal surgery and operator etc. However, a scoring system may be more useful to predict the difficulty during colonoscopy.

Methods

The individual and procedure-related data of 616 patients undergoing colonoscopy were prospectively collected from December 2013 through February 2014 in Xijing Hospital of Digestive Diseases. Cox regression analysis was used to identify high-risk factors associated with difficulty of colonoscopy. A predicting model with the difficult colonoscopy score (DCS) was developed.

Results

Total cecum intubation rate was 98.9% (609/616). Advanced age, lower BMI, inexperienced operator and fair or poor sleep quality were identified as independent factors of prolonged insertion time (all p < 0.05), which were used to develop the DCS. Based on the score, patients could be divided into high-risk and low-risk groups with distinct incomplete rates within 10 min (42.0% vs. 16.5%, p < 0.001). Compared with those with DCS ≤ 1, patients with DCS > 1 had increased insertion time (10.6 ± 0.7 min vs. 6.9 ± 0.2 min, p < 0.001) and pain score (1.9 ± 1.5 vs. 1.4 ± 1.4, p = 0.002). More abdominal compression (36.9% vs. 16.8%, p < 0.001) and position change (51.4% vs. 22.6%, p < 0.001) were needed in this group of patients.

Conclusion

Patients with DCS > 1 had longer insertion time, higher pain score and needed more abdominal compression and position changes. DCS was useful for predicting the difficulty of colonoscope intubation.

(ClinicalTrials.gov NCT02105025 05/05/2014).

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-015-0273-7) contains supplementary material, which is available to authorized users.

Spatial orientation in pathway surgery

BACKGROUND

In the field of minimally invasive surgery, specifically in pathway surgery (i.e. minimal invasive procedures carried out transluminally or through instrument-created pathways), spatial disorientation is a common experience to endoscopists. In this article, two effects that may cause spatial disorientation in pathway surgery, 'control-display compatibility' and 'local disorientation', were studied.

METHOD

A custom-developed simulator Endo-PaC was developed and used for mimicking pathway surgical scenarios. In Study 1, two ways of control-display alignment, normal mapping and mirrored mapping, were tested in combination with two control devices, thumb control and wrist control, in an orienting task using Endo-PaC. In Study 2, a tethered viewpoint was added to the virtual instrument tip. It was hypothesized that the visible tip would provide a cue of orientating direction in the reference frame during the instrument navigation. In both studies, novice participants were involved, and their performance was evaluated with regard to task time, path length travelled by the virtual tip, time and number of warnings, and subjective workload and personal preference.

RESULTS

In Study 1, normal-thumb and normal-wrist mapping yielded significantly lower means than mirrored-thumb and mirrored-wrist control for all investigated objective and subjective performance measurements. Out of 24 participants, 20 participants preferred normal control mapping. In Study 2, participants performed the task in shorter time and with shorter path length when the tip was visible tip on the monitor using a tethered viewpoint, but with a lower number and time of warnings without a visible tip.

CONCLUSION

The results of our studies show that eliminating the visual-display misalignment would greatly improve novice participants' performance, reduce the training time and their cognitive workload. A visible tip on the monitor would provide strong direction cue and shorten the performance time, but might introduce collision errors to novices and therefore requires longer training time.

Novel use of cap-assisted enteroscopy for detection of colorectal tumor in a patient with incarcerated inguinal hernia

Multiple reports have documented unsuspected inguinal hernias which result in difficulties during the colonoscopic examinations of patients. In most cases, the colonoscopy can be delayed until a surgical consult has further evaluated the inguinal hernia. This case report documents a patient who required a colonoscopy but surgical intervention for the detected inguinal hernia was not appropriate due to his co-morbid medical conditions. With the use of the combination of an enteroscope fitted with a cap and fluoroscopy, the inguinal hernia was able to be negotiated and the diagnosis of a cecal carcinoma was able to be confirmed.

Cap-assisted gastroscope versus cap-assisted colonoscope for examination of difficult sigmoid colons in a nonsedated Asian population: a randomized study

BACKGROUND

Studies have estimated that cecal intubation failure occurs with conventional colonoscopy in about 10% of cases. Various methods have been adopted to improve the cecal intubation rate, including a transparent cap and special colonoscopes.

OBJECTIVE

To assess the efficacy of using a cap-assisted gastroscope (E-cap) compared with a cap-assisted colonoscope (C-cap) for the complete examination of the colon in nonsedated patients with technically difficult sigmoid colons.

DESIGN

Randomized, controlled study.

SETTING

Tertiary-care referral center.

PATIENTS

One hundred thirty-nine patients with technically difficult sigmoid colons were studied.

INTERVENTION

Colonoscopy with either an E-cap (n = 69) or a C-cap (n = 70).

MAIN OUTCOME MEASUREMENTS

Cecal intubation rate, cecal intubation time, patient-assessed pain score, and endoscopist-assessed pain score.

RESULTS

The cecal intubation rate was significantly higher in the E-cap (65/69, 94.2%) than in the C-cap group (50/70, 71.4%; P < .0001). Patient-assessed pain (moderate to severe) was more frequently reported in the C-cap (14/70, 20.0%) than in the E-cap group (5/69, 7.2%; P = .029). Endoscopist-assessed pain (moderate to severe) was more frequently reported in the C-cap (13/70, 18.6%) than in the E-cap group (3/69, 7.2%; P = .009). For patients with a low body mass index (≤ 22 kg/m(2)), the cecal intubation rate was significantly higher in the E-cap (37/38, 97.4%) than in the C-cap group (15/29, 51.7%; P < .0001).

LIMITATIONS

Single-center experience, lack of a gastroscope control group without a cap.

CONCLUSION

The cap-assisted gastroscope is more tolerable and effective than cap-assisted colonoscope for the complete examination of the colon in patients with technically difficult sigmoid colons. (

CLINICAL TRIAL REGISTRATION NUMBER

KCT0000744.).

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.

Cap-assisted colonoscopy

Cap-assisted colonoscopy is a simple, practical, and inexpensive technique that serves several useful purposes in enhancing the performance of colonoscopy. It helps improve polyp detection by its ability to visualize otherwise blind mucosal areas on the proximal aspects of folds and flexures, although its effect on adenoma detection is inconsistent. By helping navigate the colon more efficiently, it facilitates intubation of the cecum faster, with lesser patient discomfort. Cap-assisted colonoscopy can be tried as a salvage procedure in cases of failed cecal intubation with regular colonoscopy and can be of assistance during polypectomy, especially for polyps located on the proximal aspects of folds.

Cap-assisted water immersion for minimal sedation colonoscopy: prospective, randomized, single-center trial

BACKGROUND AND AIM

Water immersion insertion is able to reduce discomfort and need for sedation during colonoscopy. A cap attached to the colonoscope tip may improve insertion during air insufflation colonoscopy. According to several reports, both techniques alone may result in higher detection of neoplastic lesions. Our study was designed to evaluate the efficacy of cap-assisted water immersion compared to water immersion colonoscopy in minimally sedated patients.

METHODS

A total of 208 consecutive outpatients were randomized to either cap-assisted water immersion (Cap Water) or water immersion colonoscopy (Water). The primary endpoint was cecal intubation time.

RESULTS

Cecal intubation time was 6.9 ± 2.9 min in Cap Water and 7.4 ± 4.2 min in the Water arm (P = 0.73). Success rate of minimal sedation colonoscopy was equal in both groups (92.9%, P = 1.00). From the endoscopist's point of view, there were non-significant trends towards lower discomfort (P = 0.06), less need for abdominal compression (P = 0.06) and lower difficulty score (P = 0.05) during Cap Water colonoscopy. Adenoma detection rate was similar in both arms (44% in Cap Water vs 45% in the Water group, P = 0.88). There were no complications recorded in the present study.

CONCLUSIONS

In comparison with water immersion without cap, cap-assisted water immersion colonoscopy was not able to shorten the cecal intubation time. However, it has the possibility of reducing patient discomfort and difficulty of colonoscope insertion. Potential impact on improved detection of neoplastic lesions has to be evaluated by further studies.

Colonoscopy using a small-caliber colonoscope with passive-bending after incomplete colonoscopy due to sharp angulation or pain

BACKGROUND

We evaluated the performance of a newly developed small-caliber (SC) colonoscope (PCF-PQ260L). This colonoscope (diameter 9.2 mm) is designed with passive-bending and high-force transmission. The SC colonoscope was used for rescue colonoscopy following incomplete colonoscopy with a standard (SD) colonoscope caused by sharp angulation, loop formation, or pain.

METHODS

Records of SC colonoscopy given to patients following an incomplete colonoscopy with the SD colonoscope and in the same session were analyzed. Cecal intubation rate, pain using a visual analog scale (0 = none, 100 = extremely painful) in the first and second colonoscopy, total time, new lesions detected with the SC colonoscopy, dosage of sedation used, and any complications were assessed. Examinations that could not be completed, because the colonoscope was not long enough to reach the cecum due to a redundant colon were excluded.

RESULTS

The records of 43 patients who were given SC colonoscopy following incomplete examinations using the SD colonoscope were reviewed. In 97.7 % of cases (42/43), cecal intubation was achieved with the SC colonoscope in the same session. The mean pain score during colonoscopy was significantly lower for the second SC colonoscopy than for the first SD colonoscopy (40.6 ± 14.1 vs. 74.5 ± 10.8, P < 0.001). Lesions were detected with the SC colonoscope in 41.8 % of cases (18/43).

CONCLUSIONS

When a colonoscopy with SD colonoscope failed due to sharp angulations, loop formation, or pain, subsequent colonoscopy with a SC colonoscope increased cecal intubation and lesion detection rates and decreased severity of reported pain.

Efficacy of cap-assisted endoscopy for routine examining the ampulla of Vater

AIM: To determine the efficacy of a cap-assisted endoscopy (CAE) to completely visualize the ampulla of Vater (AV) in patients failed by conventional endoscopy.

METHODS: A prospective study was conducted on 120 patients > 20 years of ages who visited the Health Promotion Center of Chungbuk National University Hospital for conscious sedation esophagogastroduodenoscopy (EGD) as a screening test from July to October, 2011. First, forward-viewing endoscopy was performed with reasonable effort using a push and pull method. We considered complete visualization of the AV when we could observe the entire AV including the orifice clearly, and reported the observation as complete or incomplete (partial or not found at all). Second, in cases of complete failure of the observation, an additional AV examination was conducted by attaching a short cap (D-201-10704, Olympus Medical Systems, Tokyo, Japan) to the tip of a forward-viewing endoscope. Third, if the second method failed, we replaced the short cap with a long cap (MH-593, Olympus Medical Systems) and performed a re-examination of the AV.

RESULTS: Conventional endoscopy achieved complete visualization of the AV in 97 of the 120 patients (80.8%) but was not achieved in 23 patients (19.2%). Age (mean ± SD) and gender [male (%)] were not significantly different between the complete observation and the incomplete observation groups. Additional short CAE was performed in patients in whom we could not completely visualize the AV. This group included 13 patients (10.9%) with partial observation of the AV and 10 (8.3%) in which the AV was not found. Short CAE permitted a complete observation of the AV in 21 of the 23 patients (91.3%). Patients in whom visualization of the AV failed with short CAE had satisfactory outcomes by replacing the short cap with a long cap. The additional time for CAE took an average of 141 ± 88 s. There were no complications and no significant mucosal trauma.

CONCLUSION: CAE is safe to use as a salvage method to achieve complete visualization of the AV when a regular EGD examination fails.

Benefits and limitations of cap-fitted colonoscopy in screening colonoscopy

BACKGROUND

Colonoscopy is widely used to detect colorectal cancer and to remove precancerous lesions to reduce the risk of colonic cancer.

AIMS

To examine the benefits and limitations of cap-fitted colonoscopy compared to conventional colonoscopy in terms of technical performance and colorectal adenoma detection rate.

METHODS

Screening colonoscopies performed from 2009 to 2010 with or without a transparent cap were retrospectively examined to compare the rate of successful intubation, cecal intubation time, and number, size, shape, and location of adenomas detected. An inclusion criterion was visualization of >95 % of the right colon.

RESULTS

Data from 2,301 colonoscopies (1,165 with cap-fitted colonoscopy, 1,136 without the transparent cap) were retrospectively analyzed. Procedures were performed by four experienced endoscopists. The subjects' demographic characteristics and technical performances were similar between the two methods. The only significant difference in the technical performance between the two techniques was a shorter cecal intubation time with cap-fitted colonoscopy (5.3 vs. 6.6 min; p = 0.045) by one endoscopist. The total number of adenomas detected was significantly higher with cap-fitted colonoscopy than without the cap (586 vs. 484, respectively; p < 0.0001). Adenoma detection with cap-fitted endoscopy was significantly higher in the right colon than in the left colon (19 vs. 12 %, respectively; p = 0.0001).

CONCLUSION

Cap-fitted colonoscopy did not improve the technical aspects of colonoscopy but significantly increased adenoma detection, especially in the right colon. It did not increase the detection rate of flat or depressed adenomas.

Transparent cap colonoscopy versus standard colonoscopy to improve caecal intubation

BACKGROUND

Colonoscopy is considered the gold-standard investigation for screening and diagnosis of colorectal cancer. It is also becoming increasingly desirable for assessment, management, diagnosis and follow-up of other colorectal diseases, such as inflammatory bowel diseases and acute diverticulitis. Hence, due to the increasing demand for colonoscopy, devices to advance examination techniques are highly sought-after and the colonoscope with the transparent cap could be one of these.

OBJECTIVES

To identify and review all relevant data in order to determine whether colonoscopy with a transparent cap is a more effective diagnostic tool than colonoscopy.

SEARCH METHODS

We searched the MEDLINE, EMBASE and CINAHL databases, and the Cochrane Central Register of Controlled Trials for all randomised controlled trials (RCTs) comparing the use of colonoscopy with a transparent cap with standard colonoscopy.

SELECTION CRITERIA

Studies were included if they were randomised controlled trials which compared the use of colonoscopy with a transparent cap with standard colonoscopy.

DATA COLLECTION AND ANALYSIS

Data on study methods, participants, interventions used and outcomes measured was extracted from each study. Data was entered into the Cochrane Review Manager software (RevMan 5.0, 2008) and analysed using Cochrane MetaView.

MAIN RESULTS

In the present meta-analysis, we considered 14 randomised controlled trials so far published. The findings of our work indicate that colonoscopy with transparent cap has a faster caecal intubation time when compared with standard colonoscopy. Reviewing studies individually would also seem to favour colonoscopy with transparent cap for polyp detection rate and pain during procedure but due to lack of comparable data meta-analysis was not feasible.

AUTHORS' CONCLUSIONS

This review suggests that a transparent cap on the end of the colonoscope may give a marginally faster caecal intubation time compared with standard colonoscopy. It also suggests that there is a better polyp detection rate and less pain with the cap. However, the authors feel that further randomised controlled trials in this area would provide more clinically significant information on this adjunct to colonoscopy.

Hood colonoscopy in trainees: a useful adjunct to improve the performance

BACKGROUND

The use of a transparent hood to improve colonoscopic performance has recently been proposed.

AIMS

The purpose of this study was to evaluate whether using the hood might improve the cecal intubation rate, cecal intubation time, number of attempts needed to intubate the ileo-cecal valve, and polyp detection rate in trainees.

METHODS

Patients undergoing colonoscopy (n = 378) were randomized in two groups, one studied with hood colonoscopy (n = 179) and the other (n = 199) with standard examination.

RESULTS

No differences were found between hood and standard colonoscopy with respect to cecal intubation rate (95 vs 92 %), whereas hood colonoscopy significantly shortened the cecal intubation time, the number of attempts needed to intubate the ileo-cecal valve, and the overall polyp detection rate (p < 0.01 for all these variables).

CONCLUSIONS

Hood colonoscopy might represent a useful adjunct to standard colonoscopy, especially improving the performance of endoscopic trainees.

The efficacy of cap-assisted colonoscopy in polyp detection and cecal intubation: a meta-analysis of randomized controlled trials

OBJECTIVES

The role of cap-assisted colonoscopy (CAC) in polyp detection and cecal intubation is unclear. We conducted a meta-analysis to compare the efficacy of CAC vs. standard colonoscopy (SC).

METHODS

Publications in English and non-English literatures (OVID, MEDLINE, and EMBASE) and abstracts in major international conferences were searched for controlled trials comparing CAC and SC. Outcome measures included the proportion of patients with polyps or adenomas detected, cecal intubation rate, cecal intubation time, and total colonoscopy time. The statistical heterogeneity of trials was examined and the effects were pooled by random-effects model. The risk of bias was evaluated by the assessment tool from the Cochrane Handbook. Subgroup analyses were performed for possible clinical and methodological heterogeneities.

RESULTS

From 2,358 citations, 16 randomized controlled clinical trials were included consisting of 8,991 subjects (CAC: 4,501; SC: 4,490). Mean age of subjects was 61.0 years old and 60% were males. CAC detected a higher proportion of patients with polyp(s) (relative risk (RR): 1.08; 95% confidence interval (CI): 1.00-1.17) and reduced the cecal intubation time (mean difference: -0.64 min; 95% CI: -1.19 to -0.10). Cecal intubation rate (RR: 1.00; 95% CI: 0.99-1.02) and total colonoscopy time (mean difference: -0.97 min; 95% CI: -2.33 to 0.40) were comparable between the two groups. In subgroup analyses, a short cap (≤4 mm) was associated with improved polyp detection, whereas a long cap (≥7 mm) was associated with a shorter cecal intubation time.

CONCLUSIONS

CAC demonstrated marginal benefit over SC for polyp detection and shortened the cecal intubation time.

Transparent-cap-fitted colonoscopy shows higher performance with cecal intubation time in difficult cases

AIM: To investigate the efficacy of cap-fitted colonoscopy (CFC) with regard to cecal intubation time.

METHODS: Two hundred and ninety-five patients undergoing screening colonoscopy at Gospel Hospital, Kosin University College of Medicine were enrolled in this randomized controlled trial between January and December 2010. Colonoscopies were conducted by a single endoscopist. Patient characteristics including age, sex, body mass index, history of abdominal surgery, quality of preparation, and the presence of diverticulosis were recorded.

RESULTS: One hundred and fifty patients were allocated into a CFC group and 145 into a non-CFC (NCF) group. Cecal intubations were achieved in all patients. Cecal intubation time in the CFC group was significantly shorter than in the NCF group for specific conditions: age ≥ 60 years, prior abdominal surgery, and poor bowel preparation. The number of detected adenomas was higher in the CFC group than in the NCF group (P = 0.040).

CONCLUSION: CFC facilitated shortening of the cecal intubation time in difficult cases, and was more sensitive for detecting adenomas than was NCF.

The cap-assisted technique enhances colonoscopy training: prospective randomized study of six trainees

BACKGROUND

Colonoscopy and polypectomy procedures have effectively reduced the incidence of colorectal cancer. Currently, competence in colonoscopy is an essential part of the education program for gastrointestinal (GI) trainees. However, considerable training is required for the optimal performance of a colonoscopy.

METHODS

This study involved six colonoscopy trainees, three of whom used the cap whereas the others did not. Each trainee managed 100 cases of screening colonoscopy from beginning to end. The cecal intubation success rate, cecal intubation time, polyp detection rate, adenoma detection rate, advanced adenoma detection rate, and adenocarcinoma detection rate were checked. The rate of successful cecal intubation and the cecal intubation time were reviewed every 10 cases.

RESULTS

The cecal intubation rate was 80.7 % (242/300) in the cap group and 63.3 % (190/300) in the non-cap group. The average cecal intubation time was 13.7 min in the cap group and 18.7 min in the non-cap group. The statistical analysis of these results suggested that the cap group had a significantly higher success rate (p < 0.001) and a shorter cecal intubation time (p < 0.001) than the non-cap group. However, the two groups did not differ significantly in the detection rate for polyps (45.3 vs 43 %; p = 0.565), adenomas (26.3 vs 25 %; p = 0.709), advanced adenomas (2.6 vs 0.6 %; p = 0.056), or adenocarcinomas (5.3 vs 3 %; p = 0.153).

CONCLUSION

Cap-assisted colonoscopies might help to increase the rate of cecal intubation success and shorten the cecal intubation time for GI trainees.

Transparent cap-assisted colonoscopy versus standard adult colonoscopy: a systematic review and meta-analysis

BACKGROUND

Cap-assisted colonoscopy uses a transparent plastic hood attached to the tip of the colonoscope to flatten the semilunar folds and improve mucosal exposure. Several studies have examined the effect of cap-assisted colonoscopy on polyp detection, but the data are inconsistent.

OBJECTIVE

This study aimed to evaluate whether cap-assisted colonoscopy improves the yield of colorectal neoplasia detected compared with standard colonoscopy.

DATA SOURCES

A systematic search of the PubMed, MEDLINE, Embase, and Cochrane databases identified 12 studies that met the inclusion criteria for data extraction.

STUDY SELECTION

Publications that compared cap-assisted colonoscopy vs standard colonoscopy in adults in a prospective randomized controlled study were selected for review.

MAIN OUTCOME MEASURES

The primary outcomes used for meta-analysis were cecal intubation rate, cecal intubation time, and polyp detection rate. The analysis was performed using a fixed-effect model. Outcomes were calculated as odds ratios or standardized mean differences with 95% confidence intervals. The average polyp miss rate determined by tandem colonoscopy was also calculated.

RESULTS

The outcomes of 6185 patients were studied. Cap-assisted colonoscopy detected significantly more patients with polyps (OR 1.13; p = 0.030) and had a lower average polyp miss rate (12.2% vs 28.6%) than standard colonoscopy. Cap-assisted colonoscopy had a significantly higher cecal intubation rate than standard colonoscopy (OR 1.36; p = 0.020), whereas the time to cecal intubation (standard mean difference, 0.04 min; p = 0.280) was similar for the 2 colonoscope types.

CONCLUSIONS

Cap-assisted colonoscopy is associated with improved detection of colorectal neoplasia and higher cecal intubation rates than standard adult colonoscopy.

Usefulness of cap-assisted colonoscopy during colonoscopic EMR: a randomized, controlled trial

BACKGROUND

Clinical demand for total colonoscopy is increasing. Several articles have reported on the usefulness of a cap for faster cecal intubation and reduced patient discomfort, but results for polyp and adenoma detection have been inconsistent.

OBJECTIVE

To assess the efficacy of a cap attached to the tip of a colonoscope for detection and resection of polyps by experienced colonoscopists.

DESIGN

Prospective, randomized, controlled trial.

SETTING

A tertiary referral center.

PATIENTS AND INTERVENTION

A total of 329 patients who underwent colonoscopic EMR were randomized to cap-assisted colonoscopy (CAC) (CAC group, n = 166) or regular colonoscopy (RC) (RC group, n = 163).

MAIN OUTCOME MEASUREMENTS

Cecal intubation time, total procedure time, required time for colonoscopic EMR of each polyp, and missing polyp rate.

RESULTS

The cecal intubation time in the CAC group and RC group was 5.3 ± 3.3 minutes and 5.8 ± 3.7 minutes, respectively (P = .170). The total procedure time in the CAC group and RC group was 23.0 ± 15.5 minutes and 29.2 ± 13.4 minutes, respectively (P = .626). The time required for colonoscopic EMR of each polyp in the CAC group and RC group was 3.5 ± 4.5 minutes and 4.2 ± 5.1 minutes, respectively (P = .010). The number of polyps during the initial colonoscopy in the CAC group and RC group was 2.2 ± 1.7 and 2.0 ± 1.8, respectively (P = .221). The number of detected polyps during colonoscopic EMR in the CAC group and RC group was 3.4 ± 2.7 and 2.7 ± 1.9 (P = .003). The number of missed polyps in the CAC group and RC group was 1.1 ± 1.5 and 0.8 ± 0.9 (P = .024).

LIMITATION

Single-center experience.

CONCLUSIONS

CAC may reduce the time required for colonoscopic EMR of each polyp and may also improve the polyp detection rate.

Magnifying gastroscopy using a soft black hood for difficult colonoscopy

BACKGROUND

Various methods are reported as aids to cecal intubation for cases in which colonoscopy is difficult. This study aimed to investigate prospectively whether a gastroscope with magnification function, narrow-band imaging (NBI), and a soft black hood can aid insertion in cases of difficult colonoscopy and facilitate both accurate diagnosis and safe treatment.

METHODS

This prospective study recruited 177 patients. All were examined with a magnifying gastroscope. A commercially available soft black hood was attached to the gastroscope during insertion and magnification. Difficult colonoscopy was anticipated before colonoscopy in cases of patients with at least one of the following factors: low BMI (<20 kg/m(2)), adhesion due to previous surgery, or previous colonoscopy that could not reach to the cecum. The success rate and duration of cecal intubation then were assessed. All detected lesions were evaluated by magnifying NBI and then classified as non-neoplastic or neoplastic for endoscopic diagnosis. Subsequently, all the lesions were removed and examined histologically for comparison.

RESULTS

The overall success rate of cecal intubation was 100% (177/177), and the mean time taken to reach the cecum was 5.9 min. A total of 156 lesions were detected endoscopically, and the overall diagnostic accuracy of NBI with magnification was 98.7%. No associated complications occurred.

CONCLUSION

Magnifying gastroscopy using a soft black hood and NBI is useful for cecal intubation in cases wherein colonoscopy is difficult, facilitating accurate diagnosis and safe treatment.

Transparent Cap Colonoscopy versus Standard Colonoscopy for Investigation of Gastrointestinal Tract Conditions

BACKGROUND

Colonoscopy is considered the gold-standard investigation for screening and diagnosis of colorectal cancer. It is also becoming increasingly desirable for assessment, management, diagnosis and follow-up of other colorectal diseases, such as inflammatory bowel diseases and acute diverticulitis. Hence, due to the increasing demand for colonoscopy, devices to advance examination techniques are highly sought-after and the colonoscope with the transparent cap could be one of these.

OBJECTIVES

To identify and review all relevant data in order to determine whether colonoscopy with a transparent cap is a more effective diagnostic tool than colonoscopy.

SEARCH STRATEGY

We searched the MEDLINE, EMBASE and CINAHL databases, and the Cochrane Central Register of Controlled Trials for all randomised controlled trials (RCTs) comparing the use of colonoscopy with a transparent cap with standard colonoscopy.

SELECTION CRITERIA

Studies were included if they were randomised controlled trials which compared the use of colonoscopy with a transparent cap with standard colonoscopy.

DATA COLLECTION AND ANALYSIS

Data on study methods, participants, interventions used and outcomes measured was extracted from each study. Data was entered into the Cochrane Review Manager software (RevMan 5.0, 2008) and analysed using Cochrane MetaView.

MAIN RESULTS

In the present meta-analysis, we considered for the first time all five randomised controlled trials so far performed. The findings of our work indicate that colonoscopy with transparent cap has a faster caecal intubation time when compared with standard colonoscopy. Reviewing studies individually would also seem to favour colonoscopy with transparent cap for polyp detection rate and pain during procedure but due to lack of comparable data meta-analysis was not feasible.

AUTHORS' CONCLUSIONS

This review suggests that a transparent cap on the end of the colonoscope may give a marginally faster caecal intubation time compared with standard colonoscopy. It also suggests that there is a better polyp detection rate and less pain with the cap. However, the authors feel that further randomised controlled trials in this area would provide more clinically significant information on this adjunct to colonoscopy.

Transparent cap improves patients' tolerance of colonoscopy and shortens examination time by inexperienced endoscopists

OBJECTIVE

Up to 10% of colonoscopy procedures cannot be completed and polyps may be missed because of patients' discomfort and the endoscopists' technique. The aim of this study was to test the feasibility and safety of attaching a transparent cap to improve the outcome, especially for inexperienced endoscopists.

METHODS

A total of 250 patients were randomized to undergoing either a cap-fitted colonoscopy (CCF) or a normal colonoscopy without a cap (NCCF). The procedures were performed by an experienced or inexperienced endoscopist, and the time to reach the cecum, the total colonoscopy time and the polyp detection rate were recorded. Visual analogue scales (VAS) assessing the severity of abdominal pain and distension were obtained.

RESULTS

For the experienced endoscopist there was no difference between CCF and NCCF on the time to reach the cecum and the time for the whole procedure. But for the inexperienced endoscopist, both times were significantly shorter in the CCF group than in the NCCF group (9.48 min vs. 12.45 min; 18.50 min vs. 21.89 min, respectively, P < 0.05). No complication was observed except some abdominal pain and distension. The VAS scores of abdominal pain and distension were significantly lower in CCF group than those in the NCCF group for the two endoscopists. There was no significant difference in the number of polyps found between the two groups.

CONCLUSION

A cap-fitted colonoscopy can shorten the examination time for inexperienced endoscopists. It can also reduce the patients' discomfort during the procedure.

Cap-fitted colonoscopy: a randomized, tandem colonoscopy study of adenoma miss rates

BACKGROUND

Failures of adenoma detection diminish the effectiveness of colonoscopy.

OBJECTIVE

This study investigated the impact of cap-fitted colonoscopy (CFC) on the adenoma miss rate at colonoscopy.

DESIGN

Randomized, tandem colonoscopy study.

SETTING

University hospital.

PATIENTS

This study involved patients undergoing elective screening or surveillance colonoscopy.

INTERVENTION

Patients were randomized to undergo cap-fitted (n = 52) or regular, high-definition (n = 48) colonoscopy before undergoing a second colonoscopy by the alternate method. During CFC, a plastic cap or hood was attached to the tip of the colonoscope, which was used to flatten haustral folds and improve mucosal exposure.

MAIN OUTCOME MEASUREMENTS

The primary outcome measure was the miss rate for adenomas between patients who underwent CFC first and patients who underwent regular colonoscopy first.

RESULTS

A total of 238 adenomas were detected in 67 patients (67%), with a combined overall miss rate of 27.7%, comprising 66 missed adenomas in 38 patients. Patients undergoing initial CFC had a significantly lower miss rate for all adenomas compared with that of patients undergoing regular colonoscopy (21% vs 33%, P = .039). Miss rates with CFC were significantly lower for adenomas of ≤5 mm (22% vs 35%; P = .037). There was no significant difference in per-patient miss rates between the initial CFC group (51%, n = 18) and the initial regular colonoscopy group (63%, n = 20, P = .36).

LIMITATIONS

Single-center study with two endoscopists.

CONCLUSION

CFC reduces miss rates for all adenomas and specifically for small adenomas. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT00577083).

Advances in endoscopic imaging of colorectal neoplasia

Colon cancer screening is arguably the most important activity performed by gastroenterologists. Recent decreases in rates of death from colorectal cancer indicate that screening methods such as colonoscopy have a positive impact. There is still room for improvement, however, particularly in prevention of right-sided colon cancer. Practice issues, such as making colonoscopy more comfortable, safer, and less costly, are keys to continued success in cancer prevention. Colonoscopy techniques, technologies, and quality control measures have advanced to improve detection, classification, and removal of early neoplasias. In particular, slow, careful inspection of the colon by gastroenterologists who have been trained in lesion recognition has improved rates of detection of polypoid and flat neoplasias. Image enhancement methods such as chromoendoscopy have greatly improved neoplasia detection in patients with chronic colitis, but are not widely used because they are perceived as inconvenient. More convenient methods, such as "digital" chromoendoscopy, show promise but have had mixed results. Ultra-high magnification systems, including optical magnification and confocal endomicroscopy, can be used during the colonoscopy examination to evaluate small polyps, allowing physicians to make immediate diagnoses and decisions about whether to remove polyps. In patients with inflammatory bowel disease, improved imaging techniques could eliminate the needs for analysis of randomly selected biopsy samples and resection of all (neoplastic and non-neoplastic) polyps. It is important to maintain high standards of quality for colonoscopy examination, detection, and removal of high-risk lesions, as well as to make colon cancer screening more widely accepted and affordable for the entire at-risk population.

Primary endoscopic approximation suture under cap-assisted endoscopy of an ERCP-induced duodenal perforation

Duodenal perforation during endoscopic retrograde cholangiopancreatography (ERCP) is a rare complication, but it has a relatively high mortality risk. Early diagnosis and prompt management are key factors for the successful treatment of ERCP-related perforation. The management of perforation can initially be conservative in cases resulting from sphincterotomy or guide wire trauma. However, the current standard treatment for duodenal free wall perforation is surgical repair. Recently, several case reports of endoscopic closure techniques using endoclips, endoloops, or fully covered metal stents have been described. We describe four cases of iatrogenic duodenal bulb or lateral wall perforation caused by the scope tip that occurred during ERCP in tertiary referral centers. All the cases were simply managed by endoclips under transparent cap-assisted endoscopy. Based on the available evidence and our experience, endoscopic closure was a safe and feasible method even for duodenoscope-induced perforations. Our results suggest that endoscopists may be more willing to use this treatment.

Hood-assisted colonoscopy is more effective in detection of colorectal adenomas than narrow-band imaging

BACKGROUND & AIMS

Colonoscopy, using either a transparent retractable extension device or narrow band imaging, is thought to improve colon adenoma detection. We compared the abilities of a transparent retractable extension device and narrow band imaging to detect colorectal adenomas.

METHODS

One hundred and seven patients with colonic adenomas that were detected by traditional colonoscopy were randomly assigned to groups that underwent a second colonoscopy that used either a transparent retractable extension or narrow band imaging; adenomas were removed. The principal outcome parameters were the number, size, shape, and location of adenomas detected. The patients' demographic characteristics, indications for colonoscopy, and cecal intubation times were similar between groups.

RESULTS

Use of the transparent retractable extension resulted in detection of 31% more adenomas than the initial procedure (P < .0001). The majority of newly discovered adenomas were sessile (79%; 26/33) and less than 5 mm in size (73%; 24/33). There was no significant increase in adenoma detection (5%) between first colonoscopy and second colonoscopy using narrow band imaging. Additional adenomas were found in 40.7% of patients that were examined using the transparent hood (22/54) versus 13.2% of those examined using narrow band imaging (7/53) (P = .0028).

CONCLUSIONS

Colonoscopy with a transparent retractable extension significantly improved the adenoma detection rate compared with repeat colonoscopy using narrow band imaging.

The impact of narrow band imaging in screening colonoscopy: a randomized controlled trial

BACKGROUND & AIMS

Narrow band imaging (NBI) is an imaging technique that allows a better definition of capillary pattern and improves the contrast between adenomas and the surrounding mucosa. Conflicting data exist on the ability of NBI to improve detection of colonic neoplasm; the impact of NBI is being tested in several screening scenarios. We evaluated whether the routine use of NBI, compared with white light (WL), during the withdrawal phase of screening colonoscopy improved adenoma detection.

METHODS

This randomized controlled study included consecutive 50- to 69-year-old patients with positive immunologic fecal occult blood tests. They were randomly assigned to groups that were examined with WL (n = 108) or NBI (n = 103) during the withdrawal phase of their colonoscopies. The primary end point was the adenoma detection rate. The prevalence of non-polypoid and the total number of adenomas were also evaluated.

RESULTS

The number of total and mean per-patient adenomas were 201 (1.95 +/- 2.3) and 198 (1.83 +/- 2.1) in the NBI and WL groups, respectively (P = .69). The adenoma detection rates were 57.3% for patients examined by NBI and 58.3% for those examined by WL (P = .88). A total of 41 non-polypoid adenomas were identified (26 in the NBI and 15 in the WL groups, P = .16). The flat adenoma detection rates were 21.4% and 9.3% in the NBI and WL groups, respectively (P = .019).

CONCLUSIONS

The routine use of NBI in screening colonoscopy did not increase the adenoma detection rate. NBI seems to improve the detection of flat adenomas, although additional studies are necessary.

Impact of a transparent hood on the performance of total colonoscopy: a randomized controlled trial

BACKGROUND

Clinical demand for total colonoscopy (TCS) is increasing. Improvement of the cecal intubation rate and shortening of the examination time would expand the capacity for TCS.

OBJECTIVE

To assess the efficacy of a transparent hood attached to the tip of a colonoscope for cecal intubation in TCS.

DESIGN

Prospective, randomized, controlled study.

SETTING

Single tertiary-referral center.

INTERVENTIONS

TCS.

MAIN OUTCOME MEASUREMENTS

Cecal intubation time and rate, complications, patient discomfort, and detection rate of colonic polyps.

METHODS

Patients who were to undergo screening and/or surveillance TCS for colorectal cancer were invited to participate in the study. Cecal intubation time and rate, complications, patient discomfort, and detection rate of colonic polyps were evaluated.

RESULTS

A total of 592 patients enrolled in this study were randomly allocated to the hood group and no-hood group. The mean (SD) cecal intubation time in the hood group and the no-hood group was 10.2 +/- 12.5 minutes and 13.4 +/- 15.8 minutes, respectively (P = .0241). The effect of its use was more prominent in the expert endoscopists group compared with those with moderate experience. The cecal intubation rate and the detection rate of small polyps in the 2 groups were similar. The grade of patient discomfort was significantly lower in the hood group. No complications were encountered with the use of the hood.

CONCLUSIONS

Use of a transparent hood on the tip of a colonoscope shortened the time required for cecal intubation and decreased patient discomfort; such use was more effective among experts in shortening the examination time.

Colonoscopy: Art or science?

The focus on colorectal neoplasia has led to an exponential increase in the use of colonoscopy in many countries. Although colonoscopy facilitates the diagnosis and treatment of colonic disease, there are public health issues that include access, training, diagnostic accuracy, complications and additions to health-care costs. Because of this, colonoscopists have a responsibility to ensure that the procedure is appropriate, safe and of high-quality. This article addresses the issue of variation in technical skills that is known to exist within the endoscopic community, even among individuals with similar experience. While some of this variation reflects innate manual dexterity, another aspect is variation in the adoption of technical manoeuvers that facilitate various aspects of the procedure including rates for cecal intubation. Although technical manoeuvers are difficult to evaluate in controlled trials, there is persuasive data that high cecal intubation rates can be achieved by minimizing inflation and looping in the sigmoid colon and by the appropriate use of positional changes and abdominal pressure. In difficult settings, there is also benefit from the use of non-standard endoscopes and various accessories including overtubes.

Efficacy of cap-assisted colonoscopy in comparison with regular colonoscopy: a randomized controlled trial

OBJECTIVES

Colonoscopy cannot be completed in up to 10% of cases. We postulate that cap-assisted colonoscopy (CAC), by fitting a mucosectomy cap to the tip of a colonoscope, could improve the outcome.

METHODS

We conducted a prospective randomized controlled trial in two regional endoscopy centers. All colonoscopies were performed by experienced colonoscopists. Patients 18 years or older undergoing their first colonoscopy were recruited. Patients were randomized to the CAC group or to the regular colonoscopy (RC) group. The first successful cecal intubation rate, rescue cecal intubation rate, cecal intubation and total colonoscopy times, and polyp detection rate were compared.

RESULTS

One thousand patients were enrolled (mean age 52.6 years, 46% men). There was no statistically significant difference in the first successful cecal intubation rate between CAC and RC groups (96.2% vs. 94.6%, P=0.23). The cecal intubation and total colonoscopy times were shorter in the CAC group than in the RC group (6.0+/-4.0 min vs. 7.2+/-4.8 min, P<0.001; 14.7+/-8.6 min vs. 16.7+/-10.3 min, P=0.001). The adenoma detection rate was significantly lower in the CAC group than in the RC group (30.5% vs. 37.5%, P=0.018), but there was no significant difference in the detection of advanced lesions. In case of failing cecal intubation, use of CAC as a rescue method could achieve a higher success rate than RC (66.7% vs. 21.1%, P=0.003).

CONCLUSIONS

Among experienced colonoscopists, CAC did not improve the initial cecal intubation rate and had a lower adenoma detection rate. However, it shortened the cecal intubation time and performed better as a rescue method. Its utilization should be reserved for selected cases, especially when initial cecal intubation fails.

Not your father's colonoscopy: a high-tech future for screening and surveillance of colorectal cancer

The 20-year technology slump in endoscopic innovation is finally giving way to a flurry of technologies, of which many are directed specifically at improving or even replacing traditional colonoscopy. These technologies include "smart" overtubes, electronically mapped and driven instruments, and completely self-propelled devices. In addition to nonendoscopic technologies such as CT, these innovations may dramatically alter the practice of colorectal cancer screening, the "bread and butter" of gastroenterologists in this country. There are multiple and complex forces driving these changes, including a mismatch between the supply and demand in colonoscopy, patient convenience and comfort, costs, and more recently, a growing concern about the miss rate of conventional colonoscopy.

A motor-driven single-use colonoscope controlled with a hand-held device: a feasibility study in volunteers

BACKGROUND

Several new instruments have been developed in the effort to improve the acceptance of colonoscopy for colorectal cancer screening. A new colonoscope, the Invendoscope, is presented here. It consists of an endoscopic sheath with an inverted sleeve, instrument channel, and an electrohydraulic deflecting tip. The instrument is steered by a hand-held device and propelled by a motorized drive unit.

OBJECTIVE

Our purpose was to evaluate the feasibility of the new Invendoscope SC40.

DESIGN

Prospective single-arm pilot study over 2 time periods using 2 different instrument prototypes (170 and 180/200 cm).

PATIENTS

Thirty-four healthy volunteers (19 men, mean age 49.7 years). Technical instrument defects led to premature termination in 5 additional volunteers during the 2 study periods (4 in phase 1, 1 in phase 2), who were excluded from further analysis.

INTERVENTIONS

Total colonoscopy was attempted, with all procedures being performed without sedation.

MAIN OUTCOME MEASUREMENTS

Cecal intubation rate.

RESULTS

The cecum was reached in 82% of the 34 cases (95% CI, 66%-92%), with better results in period 2 than in period 1 (90% vs 79%); of the 6 incomplete examinations, 4 reached the mid transverse colon or beyond and 2 were stopped in the sigmoid colon because of pain. The volunteer rating showed a mean score of 1.96 (range 1-6; 1 = no discomfort). No complications were encountered.

LIMITATIONS

No data regarding diagnostic accuracy and no data comparing the instrument with conventional colonoscopy are available as yet.

CONCLUSIONS

This pilot proof-of-principle study of a new motor-driven colonoscope showed promising cecal intubation rates and an absence of pain in 92% of cases. Further clinical and comparative studies are warranted.