Alternatives to Incomplete Colonoscopy

Strategies to manage the difficult colonoscopy

During endoscopy, an endoscopist is inevitably faced with the occasional “difficult colonoscopy,” in which the endoscopist finds it challenging to advance the endoscope to the cecum. Beyond optimization of technique, with minimized looping, minimal insufflation, sufficient sedation, and abdominal splinting when needed, sometimes additional tools may be needed. In this review, we cover available techniques and technologies to help navigate the difficult colonoscopy, including the ultrathin colonoscope, rigidizing overtube, balloon-assisted colonoscopy and the abdominal compression device.

Feasibility of salvage colonoscopy by water exchange for failed air-insufflated patients: a prospective, randomized, controlled trial

BACKGROUND

A complete colonoscopy is crucial for screening colorectal diseases and colorectal cancer. However, a failure rate of up to 43% still exists. Several studies have indicated that the water exchange method can enhance the cecal intubation rate while reducing discomfort of the patient. Water exchange colonoscopy (WEC) might be a salvage treatment for the patients who failed from air insufflation colonoscopy (AIC). We aimed to assess the feasibility of WEC as a salvage measure following the failure of conventional AIC.

METHODS

Patients willing to undergo unsedated colonoscopy at a tertiary-care referral center in China were randomly assigned 1:1 to WEC or AIC group for salvage after the initial AIC attempt failed. Patients were blinded to group assignment. The primary outcome was cecal intubation rate, the secondary outcomes included time to the cecum, maximum pain scores, and technical difficulty level.

RESULTS

Recruited 104 patients were randomized to the WEC (n = 52) or AIC (n = 52) group. WEC significantly increased the cecal intubation rate (92.3% vs 73.1%; p = .02). The maximum pain scores and technical difficulty level in the WEC group were significantly lower than the AIC group during salvage procedure (p < .001).

CONCLUSIONS

This randomized, controlled trial confirms that the WEC significantly enhanced cecal intubation rate in difficult colonoscopy in unsedated patients after the failure of standard AIC. The increased cecal intubation rate, lower pain scores and technical difficulty level suggest WEC is a good alternative for incomplete unsedated colonoscopy. Clinical trial registration number: ChiCTR2100051483.

Scoring Systems for Clinical Colon Capsule Endoscopy-All You Need to Know

In the constantly developing era of minimal diagnostic invasiveness, the role of colon capsule endoscopy in colonic examination is being increasingly recognised, especially in the context of curtailed endoscopy services due to the COVID-19 pandemic. It is a safe diagnostic tool with low adverse event rates. As with other endoscopic modalities, various colon capsule endoscopy scores allow the standardisation of reporting and reproducibility. As bowel cleanliness affects CCE’s diagnostic yield, a few operator-dependent scores (Leighton–Rex and CC-CLEAR scores) and a computer-dependent score (CAC score) have been developed to grade bowel cleanliness objectively. CCE can be used to monitor IBD mucosal disease activity through the UCEIS and the panenteric CECDAIic score for UC and CD, respectively. CCE may also have a role in CRC screening, given similar sensitivity and specificity rates to conventional colonoscopy to detect colonic polyps ≥ 10 mm and CRC. Given CCE’s diagnostic yield and reproducible clinical scores with high inter-observer agreements, CCE is fast becoming a suitable alternative to conventional colonoscopy in specific patient populations.

The Impact of Sedation on Adenoma Detection Rate and Cecal Intubation Rate in Colonoscopy

Purpose

To explore the effect of sedation on the quality of colonoscopy.

Methods

The data collected from the Digestive Endoscopy Center of Shanghai Tongji Hospital from March 2012 to June 2019 were retrospectively analyzed. The rate of sedation and quality metrics of colonoscopy such as adenoma detection rate (ADR) and cecal intubation rate (CIR) were calculated. The logistic regression model was used to explore the relationship between sedation and quality metrics of colonoscopy. The interaction effects between experience of endoscopists and sedation on quality of colonoscopy was also investigated in subgroups stratified by total number of colonoscopies during career using the logistic regression model.

Results

A total of 63,417 colonoscopies including 11,417 colonoscopies without sedation and 52,000 colonoscopies with sedation were enrolled in our study. The proportion of colonoscopy with sedation was 82.0%. The ADR and CIR were all significantly higher in cases with sedation compared with cases without sedation (ADR, 22.5% vs. 17.0%, p < 0.001; CIR, 94.7% vs. 91.2%, p < 0.001). Multivariate analysis showed that the sedation was an independent factor associated with adenoma detection (OR = 1.448, 95% CI: 1.372~1.529, p < 0.001) and cecal intubation (OR = 1.560, 95% CI: 1.446~1.683, p < 0.001). A total of 14 endoscopists with complete colonoscopy data in our database and corresponding 20,949 colonoscopies data were enrolled for further analysis. The logistic regression model yielded a similar result that sedation was an independent factor on adenoma detection and cecal intubation when the factor, experience of endoscopists, was also entered into the model as a confounder (adenoma detection, OR = 1.408, 95% CI: 1.333~1.487, p < 0.001; cecal intubation, OR = 1.601, 95% CI: 1.482-1.729, p < 0.001).

Conclusion

Colonoscopy with sedation has a positive effect on ADR and CIR in all endoscopists with different experience of colonoscopy, which makes the quality of colonoscopy better.

Incidence of clinically significant perforation at low dose non-contrast CT and its value prior to same day CT colonography following incomplete colonoscopy

PURPOSE

Routine low dose non-contrast CT of the abdomen and pelvis has been suggested prior to same day completion CT colonography (CTC) to assess for occult perforation at preceding incomplete colonoscopy, before further gaseous insufflation at CTC. The aim of our study is to examine the incidence of clinically significant perforation at low dose CT. We also examine the benefits of low dose pre-scan in assessing adequacy of bowel preparation and identifying any other relevant contraindications to CT colonography.

MATERIALS AND METHODS

We conducted a retrospective review of all low dose non-contrast CTs performed following failed colonoscopies over a 4-year period (n = 392). We also assessed the adequacy of bowel preparation on a scale of 1-5, in order of increasingly adequate preparation. Incidentally noted bowel pathology and contraindications to CT colonography were also recorded.

RESULTS

No perforation was identified either prospectively or in the course of our retrospective review. However, 15 patients (3.8%) were found to have potential contraindications to CT colonography, including: acute diverticulitis, acute colitis, and poor bowel preparation. Overall, the bowel preparation was felt to be adequate (≥ 3) in 86% percent of patients. Two patients (0.5%) identified prospectively had their CT colonography postponed due to poor bowel preparation.

Emerging next-generation robotic colonoscopy systems towards painless colonoscopy

Advances in the field of robotics have allowed modern technology to be integrated into medicine and that can minimize patients suffering from the side effects that are inherent to procedures for improving their quality of life. Conventional devices that are used for colonoscopies are rigid and require a high level of expertise from endoscopists to perform the procedure. Advances in robot-assisted colonoscopic systems now produce softer, more slender, automated designs that no longer require the operator to use forceful pushing to advance the colonoscope inside the colon, reducing risks to the patient of perforation and pain. It is challenging to reprocess these scopes for reuse as the materials used can be damaged during decontamination, leading to the possible risks of cross-infection by pathogenic microorganisms when reused by patients. An ideal solution is to eliminate these contamination risks to patients by adopting sterile, single-use scopes straight from the manufacturer's package to the patient. With this idea in mind, emerging developments that push the boundaries in this area will benefit patients and encourage the public to participate in and adhere better to colonoscopy screening to reduce the development of colorectal cancer. Thus, in light of these concerns and challenges, to encourage patients undergoing colorectal screening to comply with colonoscopy procedures that they are less invasive, changes in the design and materials are necessary. One of the more promising technological advances in this area is the advent of robotic colonoscopy.

New technologies improve adenoma detection rate, adenoma miss rate, and polyp detection rate: a systematic review and meta-analysis

BACKGROUND AND AIMS

The need to increase the adenoma detection rate (ADR) for colorectal cancer screening has ushered in devices that mechanically or optically improve conventional colonoscopy. Recently, new technology devices (NTDs) have become available. We aimed to compare the ADR, polyp detection rate (PDR), and adenoma miss rate (AMR) between NTDs and conventional colonoscopy and between mechanical and optical NTDs.

METHODS

MEDLINE and Embase databases were searched from inception through September 2017 for articles or abstracts reporting ADR, PDR, and AMR with NTDs. Randomized controlled trials and case-control studies with >10 subjects were included. Primary outcomes included ADR, PDR, and AMR odds ratio (OR) between conventional colonoscopy and NTDs. Secondary outcomes included cecal intubation rates, adverse events, cecal intubation time, and total colonoscopy time.

RESULTS

From 141 citations, 45 studies with 20,887 subjects were eligible for ≥1 analyses. Overall, the ORs for ADR (1.35; 95% confidence interval [CI] 1.24-1.47; P < .01) and PDR (1.51; 95% CI, 1.37-1.67; P < .01) were higher with NTDs. Higher ADR (OR, 1.52 vs 1.25; P = .035) and PDR (OR, 1.63 vs 1.10; P ≤ .01) were observed with mechanical NTDs. The overall AMR with NTDs was lower compared with conventional colonoscopy (OR, .19; 95% CI, .14-.26; P < .01). Mechanical NTDs had lower AMRs compared with optical NTDs (OR, .10 vs .33; P < .01). No differences in cecal intubation rates, cecal intubation time, or total colonoscopy time were found.

CONCLUSIONS

Newer endoscopic technologies are an effective option to improve ADR and PDR and decrease AMR, particularly with mechanical NTDs. No differences in operability and safety were found.

Single Balloon-assisted Colonoscopy for Placement of Colonic Manometry Catheters: Initial Experience in Children

OBJECTIVES

Colonic manometry is used frequently in children with long standing and difficult to manage constipation to aid in management decisions. Accurate analysis requires placement of the colonic manometry catheter in the colon without looping. This is technically difficult due to the long-standing nature of the constipation in most patients leading to sigmoid and other colonic redundancy. Single balloon colonoscopy has been successfully used in adult in cases of difficult colonoscopy. We report the first series of single balloon-assisted colonoscopy for performing difficult colonoscopy in children and placing colonic manometry catheters.

METHODS

Retrospective chart review was performed to identify patients undergoing the procedure. All patients had prior preparation with nasogastric golytely.

RESULTS

Using the single balloon technique, 36 patients underwent placement of the colonic manometry catheter (ages ranging from 3 to 16 years, weights 12 to 95 kg). Catheter placement was successful in all cases with procedure times of 20 to 105 minutes. No major complications were noted.

CONCLUSIONS

This is the first reported series of using single balloon-assisted colonoscopy to perform difficult colonoscopy in children and place colonic manometry catheters. It may have other therapeutic implications in children such as removal of polyps or placement of similar catheters.

High Efficacy of Repeating Colonoscopy by an Advanced Endoscopist after an Incomplete Colonoscopy

Background and Aims

This study aims to evaluate the role of an advanced endoscopist to study the entire colon after an incomplete colonoscopy.

Methods

All patients with an elective incomplete colonoscopy performed under deep sedation in our department between January 2010 and October 2016 were included. Patients with a colonic stenosis, an inadequate bowel preparation, or a colonoscopy performed without deep sedation were excluded. Included patients were followed up to evaluate if and what type of subsequent examinations (colonoscopy by an advanced endoscopist, single-balloon enteroscopy [SBE], and/or CT colonography) was performed to complete the study of the entire colon. Lesions found during these subsequent examinations were also recorded.

Results

Ninety-three patients had an incomplete colonoscopy, with no diagnosis of colorectal cancer (CRC) and a high-risk polyp rate of 5.4% (n = 5). Seventy-seven patients with incomplete colonoscopies underwent subsequent examinations, namely CT colonography in 45.5% (n = 35), colonoscopy by an advanced endoscopist in 53.2% (n = 41), and SBE in 13% (n = 10). In the 49 patients who performed either colonoscopy (n = 39) or SBE (n = 10) by an advanced endoscopist, the cecal intubation rate was 100%, and high-risk polyps were found in 26.5% (n = 13) and CRC in 4.1%. CT colonography revealed findings consistent with polyps and CRC in 22.9% (n = 8) and 2.9% (n = 1) of the cases, respectively. Colonoscopy was further repeated in 6 patients with suspected polyps in CT colonography, confirming the initial diagnosis in 5 patients.

Conclusions

Colonoscopy by an advanced endoscopist achieved cecal intubation in all patients, representing a good choice after an incomplete colonoscopy.

Contribution of intraoperative colonoscopy in a colorectal surgery unit. Scand J Gastroenterol 2017;52:1292-1297. [PMID: 28768440 DOI: 10.1080/00365521.2017.1362465]

OBJECTIVES

Intraoperative colonoscopy (IC) is routinely used in colorectal surgery procedures, both oncologic and benign ones. Despite its extensive use there is a lack of literature addressing this important issue. The aims of this paper are to determine the contributions of this tool, especially considering changes in attitude from preoperative designed intervention.

MATERIALS AND METHODS

This study is a retrospective analysis of a prospective maintained database. Patients who underwent colorectal resection and IC during a four-year period (2009-2012). The indications for performing IC in our unit are: Incomplete preoperative colonoscopy, confirm the exact location of the tumor and polypectomy of any lesion distant from the planned resection segment.

RESULTS

The success rate in performing IC is 100%, including 42% of them made trans-anastomotic. No postoperative complications that were attributable to the endoscopy were detected. Routine practice led to a change in attitude in 5% of the patients analyzed; 2% of the global sample corresponded to synchronous tumors finding. Of those patients in whom polypectomies where achieved during the procedure a 14.3% of potentially malignant lesions were resected.

CONCLUSIONS

Intraoperative colonoscopy is a useful and safe tool that in view of these results should be taken into account at any colorectal surgery unit. Trans-anastomotic techniques do not raise morbidity.

Cap-assisted colonoscopy versus standard colonoscopy: is the cap beneficial? A meta-analysis of randomized controlled trials

Background:

In an effort to improve visualization during colonoscopy, a transparent plastic cap or hood may be placed on the end of the colonoscope. Cap-assisted colonoscopy (CAC) has been studied and is thought to improve polyp detection. Numerous studies have been conducted comparing pertinent clinical outcomes between CAC and standard colonoscopy (SC) with inconsistent results.

Methods:

Numerous databases were searched in November 2016. Only randomized controlled trials (RCTs) involving adult subjects that compared CAC to SC were included. Outcomes of total colonoscopy time, time to cecum, cecal intubation rate, terminal ileum intubation rate, polyp detection rate (PDR), and adenoma detection rate (ADR) were analyzed in terms of odds ratio (OR) or mean difference (MD) with fixed effect and random effects models.

Results:

Five hundred eighty-nine articles and abstracts were discovered. Of these, 23 RCTs (n=12,947) were included in the analysis. CAC showed statistically significant superiority in total colonoscopy time (MD -1.51 min; 95% confidence interval [CI] -2.67 to -0.34; P<0.01) and time to cecum (MD -0.82 min; 95%CI -1.20 to -0.44; P<0.01) compared to SC. CAC also showed better PDR (OR 1.17; 95%CI 1.06-1.29; P<0.01) but not ADR (OR 1.11; 95%CI 0.95-1.30; P=0.20). In contrast, on sensitivity analysis, ADR was better with CAC. Terminal ileum intubation and cecal intubation rates demonstrated no significant difference between the two groups (P=0.11 and P=0.73, respectively).

Conclusions:

The use of a transparent cap during colonoscopy improves PDR while reducing procedure times. ADR may improve in cap-assisted colonoscopy but further studies are required to confirm this.

Video capsule colonoscopy in routine clinical practice

BACKGROUND

Colon capsule endoscopy (CCE) offers direct mucosal visualisation without sedation or gas insufflation required in conventional colonoscopy (CC). However, evidence for the role of CCE as an adjunct or alternative to CC remains equivocal. In this observational cohort study, we report our experience of using CCE to investigate patients with suspected colon pathology at a tertiary referral centre.

METHODS

From 2007-2015, consecutive patients requiring colonoscopy were recruited from a tertiary care centre in Malmo, Sweden. Data collected: patient demographics, indication for CCE, findings, bowel cleansing, colon transit time (CTT) and completeness of colon examination.

RESULTS

Seventy-seven patients (57 F/20 F, median age 56 years) were included. The reason for CCE was previously incomplete or refused CC in 39 and 26 cases, and follow up of previous findings in 12 cases, respectively. The main clinical indications were gastrointestinal (GI) bleeding (n=28; 36%) and suspected inflammatory bowel disease (IBD) or follow-up of known IBD (n=23; 30%). CCE was complete in 58/77 (75%) patients. In 3 patients the colon was not reached; in the other 16, the capsule reached the rectum (n=4), sigmoid (n=6), descending colon (n=5) and transverse colon (n=1). Findings were: normal CCE (n=15; 19%) colonic diverticula (n=29; 38%), polyps (n=17; 22%), active IBD (n=12; 16%), haemorrhoids (n=8; 10%), colonic angioectasia (n=4; 5%) and cancer (n=1; 1%). Small-bowel findings were recorded in 8 (10%) patients. All patients tolerated bowel preparation and CCE well. Two patients with an ulcerated small-bowel stricture and cancer respectively experienced temporary capsule retention with spontaneous resolution.

CONCLUSIONS

CCE is a well-tolerated alternative to CC, but requires technological improvement and optimisation of clinical practice to meet current reference standards. Although further technical development is required, CCE may complement or even replace CC for certain clinical indications.

Is capsule colonoscopy the solution for incomplete conventional colonoscopy?

The era of colon capsule endoscopy (CCE) started in 2007. Few years later second-generation CCE (CCE-2) (Medtronic, Minneapolis, USA) was launched, featuring an improved optical system allowing for nearly 360° coverage via two 172° angle cameras, and adaptive frame rate function (ranging from 4 to 35 images per second depending on capsule motion). At present the main clinical indications for CCE are: a) completion of incomplete colonoscopy; b) polyp detection; and c) investigation of inflammatory bowel disease (IBD).

Review: capsule colonoscopy-a concise clinical overview of current status

The colon capsule endoscopy (CCE) was first introduced in 2007. Currently, the main clinical indications for CCE are completion of incomplete colonoscopy, polyp detection and investigation of inflammatory bowel disease (IBD). Although conventional colonoscopy is the gold standard in bowel cancer screening, incomplete colonoscopy remains a problem as lesions are missed. CCE compares favourably to computer tomography colonography (CTC) in adenoma detection and has therefore been proposed as a method for completing colonoscopy. However the data on CCE remains sparse and current evidence does not show its superiority over CTC or conventional colonoscopy in bowel cancer screening. CCE also seems to show good correlation with conventional colonoscopy when used to evaluate IBD, but there are not many published studies at present. Other significant limitations include the need for aggressive bowel preparation and the labour-intensiveness of CCE reading. Therefore, much further software and hardware development is required to enable CCE to fulfill its potential as a minimally-invasive and reliable method of colonoscopy.

PillCam colon capsule endoscopy (PCCE) in colonic diseases

Diseases affecting the colon are common worldwide and can cause a major health problem. Colorectal cancer (CRC) as well as Inflammatory bowel diseases represent a major cause of morbidity and mortality in western countries. PillCam colon capsule endoscopy (PCCE) is a novel and promising technology that can be useful for the screening and monitoring of colonic diseases. In the recent years many articles examined the use of various versions of PCCE-the 1st and 2nd generation versus various other endoscopic or radiologic modalities both for detection of colonic polyps or cancer and in both ulcerative colitis (UC) and Crohn's disease. The aim of the current review is to provide up to date information regarding the use and usefulness of this method in these disease.

Accrediting for screening-related colonoscopy services: What is required of the endoscopist and of the endoscopy service?

Colorectal cancer (CRC) screening is widely implemented to reduce CRC incidence and related mortality. The impact of screening as well as the balance between screening burden and benefits strongly depends on the quality of colonoscopy. Besides quality, safety of the endoscopic procedure and patient satisfaction are important outcome parameters for a screening program. Therefore the requirements for both CRC screening endoscopy services and endoscopists focus on technical aspects, patient safety, and patient experience. Stringent quality assurance by means of routine monitoring of quality indicators for the performance of endoscopists and endoscopy units is recommended. This allows setting minimum standards, targeted interventions, and enhancement of the overall quality of population screening. This reviews deals with guidelines and quality standards for colorectal cancer screening, with focus on both endoscopist and endoscopy services.