Factors associated with incomplete colonoscopy at a Japanese academic hospital

Optimization of colonoscopy quality: Comprehensive review of the literature and future perspectives

Colonoscopy is crucial in preventing colorectal cancer (CRC) and reducing associated mortality. This comprehensive review examines the importance of high-quality colonoscopy and associated quality indicators, including bowel preparation, cecal intubation rate, withdrawal time, adenoma detection rate (ADR), complete resection, specimen retrieval, complication rates, and patient satisfaction, while also discussing other ADR-related metrics. Additionally, the review draws attention to often overlooked quality aspects, such as nonpolypoid lesion detection, as well as insertion and withdrawal skills. Moreover, it explores the potential of artificial intelligence in enhancing colonoscopy quality and highlights specific considerations for organized screening programs. The review also emphasizes the implications of organized screening programs and the need for continuous quality improvement. A high-quality colonoscopy is crucial for preventing postcolonoscopy CRC- and CRC-related deaths. Health-care professionals must develop a thorough understanding of colonoscopy quality components, including technical quality, patient safety, and patient experience. By prioritizing ongoing evaluation and refinement of these quality indicators, health-care providers can contribute to improved patient outcomes and develop more effective CRC screening programs.

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.

The optimal use of colon capsule endoscopes in clinical practice

Colon capsule endoscopy (CCE) has been available for nearly two decades but has grappled with being an equal diagnostic alternative to optical colonoscopy (OC). Due to the COVID-19 pandemic, CCE has gained more foothold in clinical practice. In this cutting-edge review, we aim to present the existing knowledge on the pros and cons of CCE and discuss whether the modality is ready for a larger roll-out in clinical settings. We have included clinical trials and reviews with the most significant impact on the current position of CCE in clinical practice and discuss the challenges that persist and how they could be addressed to make CCE a more sustainable imaging modality with an adenoma detection rate equal to OC and a low re-investigation rate by a proper preselection of suitable populations. CCE is embedded with a very low risk of severe complications and can be performed in the patient's home as a pain-free procedure. The diagnostic accuracy is found to be equal to OC. However, a significant drawback is low completion rates eliciting a high re-investigation rate. Furthermore, the bowel preparation before CCE is extensive due to the high demand for clean mucosa. CCE is currently not suitable for large-scale implementation in clinical practice mainly due to high re-investigation rates. By a better preselection before CCE and the implantation of artificial intelligence for picture and video analysis, CCE could be the alternative to OC needed to move away from in-hospital services and relieve long-waiting lists for OC.

Colonoscopy Insertion in Patients with Gastrectomy: Does Position Impact Cecal Intubation Time?

BACKGROUND

A history of abdominal surgery is associated with difficulty in colonoscopy insertion. Few studies have reported effective colonoscopy insertion for patients who underwent abdominal surgery due to stomach cancer.

AIM

We aimed to compare the impact of supine position (SP) and left lateral position (LLP) as the starting position of colonoscopy insertion in patients who underwent abdominal surgery due to stomach cancer.

METHODS

This was a prospective, randomized controlled trial. Patients undergoing colonoscopy for screening or post-polypectomy surveillance after gastrectomy due to stomach cancer were enrolled and randomized to the SP or LLP group as the starting position of colonoscopy insertion. All colonoscopic examinations were performed with a transparent cap. The primary outcome was to compare the cecal intubation time between the two groups.

RESULTS

A total of 224 patients were enrolled. The mean cecal intubation time was not significantly different between the SP and LLP groups (364.5 s versus 306.9 s; p = 0.105). In patients with a lower body mass index (< 21 kg/m²) or who underwent gastrectomy within three years, the mean cecal intubation time of the LLP group was shorter than the SP group. In the multivariate analysis for the factors affecting to increase in the cecal intubation time (> 5 min), the starting position was not an independent factor.

CONCLUSION

Either the SP or LLP could serve as a possible starting position of colonoscopy insertion for patients who underwent abdominal surgery due to stomach cancer.

Strategies to minimise the current disadvantages experienced by women in faecal immunochemical test-based colorectal cancer screening

Currently, women are disadvantaged compared to men in colorectal cancer (CRC) screening, particularly in programmes that use faecal immunochemical tests for haemoglobin (FIT) followed by colonoscopy. Although there is no single cause for all the known disadvantages, many can be attributed to the ubiquitous finding that women have lower faecal haemoglobin concentrations (f-Hb) than men; there are many plausible reasons for this. Generally, a single f-Hb threshold is used in CRC screening programmes, leading to lower positivity for women than men, which causes poorer outcomes for women, including lower CRC detection rate, higher interval cancer (IC) proportion, and higher CRC mortality. Many of the now widely advocated risk scoring strategies do include factors taking account of sex, but these have not been extensively piloted or introduced. Using different f-Hb thresholds for the sexes seems advantageous, but there are difficulties, including deciding which characteristic should be selected to achieve equivalency, for example, positivity, IC proportions, or specificity. Moreover, additional colonoscopy resources, often constrained, would be required. Governments and their agencies should be encouraged to prioritise the allocation of resources to put simple strategies into practice, such as different f-Hb thresholds to create equal positivity in both sexes.

Capsule Endoscopy Versus Colonoscopy in Patients With Previous Colorectal Surgery: A Prospective Comparative Study

Background

Colonic capsule endoscopy (CCE) derived from the video capsule endoscopy, initially proposed to explore the small bowel, has demonstrated high sensitivity and specificity for colonic polyp detection. The primary outcome of the study was to assess the safety, feasibility, and reliability of CCE after colorectal surgery. Secondary outcomes were to identify the detection rate of colonic lesions and recognition of the surgical anastomosis as compared to colonoscopy.

Methods

This is a prospective single-center study conducted over a 2-year period. Thirty-seven patients with a history of colorectal surgery were prospectively included in this study. Each patient received both CCE and colonoscopy, performed by different operators blinded to each other’s results.

Results

Thirty-two patients (86.5%) completed the study and were included in the final analysis. All capsules were naturally expelled. In three patients (9.4%), the anal verge was not identified during the CCE recording and the examination of the colon was considered incomplete. Surgical anastomosis was accurately identified by CCE in 78.2% of the patients versus 93.8% for colonoscopy (P = 0.65). Thirty-eight lesions were detected in 14 patients. The sensitivity of CCE to detect colonic polyps was 95.2% (95% confidence interval (CI): 77.3-99.2%), the specificity 82.4% (95% CI: 59.0-93.8%). Positive predictive value (PPV) and negative predictive value (NPV) of CCE to detect colonic polyps were 87.0% and 93.3%, respectively. No complications related to the passage of the capsule through the intestinal anastomosis were detected.

Conclusions

CCE proved to be safe and feasible, reporting a similar detection rate of colonic lesion compared to colonoscopy.

Extension Mechanism of a Flexible End for Colonoscopy

Introduction

The significance of the distal tip extension mechanism (DTEM) arises when the insertion tube of the colonoscope is no longer able to move further inside the colon, and when a longer insertion tube is needed. The main focus of this research is to investigate the development of a novel distal tip extension mechanism (DTEM).

Methods

To characterize the performance of the DTEM, the ability of the DTEM to extend the distal tip of the colonoscope 16 cm is investigated. To determine the maximum number of turns that the extension knob needs to make in order to move the distal tip 16 cm, the DTEM is used to displace the distal tip in different colon configurations using the silicon tube of a colonoscopy training model (CTM). The experimentally collected data was presented and discussed to characterize the performance of the DTEM.

Results

The results showed that the DTEM is able to extend the distal tip 16 cm while the colon is in various configurations. Additionally, the impact of implanting the DTEM on the flexibility of the insertion tube was determined.

Discussion

The results of this research suggest that the DTEM will be an effective tool to help colonoscopists performing better colonoscopies.

COVID-19 recovery: tackling the 2-week wait colorectal pathway backlog by optimising CT colonography utilisation

AIM

To review the indications for computed tomography colonography (CTC) performed on patients referred via the 2-week wait colorectal pathway (2WWCP).

MATERIALS AND METHODS

A retrospective study was performed on all patients referred through the 2WWCP between October 2018 and September 2019. The referrals were audited against the National Institute for Health and Care Excellence (NICE) NG12/DG30 guidelines for referral to the 2WWCP, and against the Royal College of Radiologists (RCR) 2017 guidelines for CTC.

RESULTS

Over the study period, there were 1,707 2WWCP referrals, and 362 (21.2%) of these patients underwent CTC. The median age was 66 years, and 55% were female. Forty-six patients did not meet the NICE NG12/DG30 guidelines for referral to the 2WWCP, and a further 268, although meeting the NICE guidelines, did not meet the RCR 2017 guidelines for CTC. In total, only 13% of CTCs performed complied with both guidelines.

CONCLUSION

This audit demonstrated a significant opportunity to reallocate CTC resources in the recovery stage of the COVID-19 pandemic. To improve outcomes for colorectal cancer (CRC) in the UK, establishing a selective straight-to-test CTC 2WWCP should be considered. Documented consent detailing the risks and benefits of CTC versus colonoscopy should take place in order to assist the patient in making an informed choice.

Computed Tomography Colonography Versus Standard Optical Colonoscopy for the Detection of Colorectal Polyp in Patients Who Faced Curative Surgery for Colorectal Cancer: A Diagnostic Performance Study

Data regarding computed tomography colonography, standard optical colonoscopy, and enhanced colonoscopy/histopathology at 1-year after surgery and at 6-month intervals for the next 2 years of 345 patients who faced curative surgery for colorectal cancer were included in this analysis. Computed tomography colonography and standard optical colonoscopy both detected 298 polyps as suspicious. With reference to enhanced colonoscopy/histopathology, sensitivities for the detection of any polyps for computed tomography colonography and standard optical colonoscopy were 0.952 and 0.906, while, accuracies were 0.783 and 0.641, respectively. Computed tomography colonography may be a sensitive and accurate surveillance tool for colorectal cancer patients.

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.

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.

Comorbid chronic diseases and cancer diagnosis: disease-specific effects and underlying mechanisms

An earlier diagnosis is a key strategy for improving the outcomes of patients with cancer. However, achieving this goal can be challenging, particularly for the growing number of people with one or more chronic conditions (comorbidity/multimorbidity) at the time of diagnosis. Pre-existing chronic diseases might affect patient participation in cancer screening, help-seeking for new and/or changing symptoms and clinicians' decision-making on the use of diagnostic investigations. Evidence suggests, for example, that pre-existing pulmonary, cardiovascular, neurological and psychiatric conditions are all associated with a more advanced stage of cancer at diagnosis. By contrast, hypertension and certain gastrointestinal and musculoskeletal conditions might be associated with a more timely diagnosis. In this Review, we propose a comprehensive framework that encompasses the effects of disease-specific, patient-related and health-care-related factors on the diagnosis of cancer in individuals with pre-existing chronic illnesses. Several previously postulated aetiological mechanisms (including alternative explanations, competing demands and surveillance effects) are integrated with newly identified mechanisms, such as false reassurances, or patient concerns about appearing to be a hypochondriac. By considering specific effects of chronic diseases on diagnostic processes and outcomes, tailored early diagnosis initiatives can be developed to improve the outcomes of the large proportion of patients with cancer who have pre-existing chronic conditions.

Time to colonoscopy, cancer probability, and precursor lesions in the Danish colorectal cancer screening program

Purpose

The aim of this study was to investigate the effect of response time from the Fecal Immunochemical Test (FIT) based screening invitation to the conclusive screening Optical Colonoscopy (OC) on the risk of detecting colorectal cancer (CRC), advanced stage disease and precursor lesions.

Patients and methods

We used a cross-sectional study design and included all 62,554 screening participants registered in the Danish Colorectal Cancer Screening Database who tested FIT-positive between March 2014 and December 2016. The main exposure was response time, measured as the time from initial invitation to the conclusive OC. Our main outcomes were the probability of being diagnosed with CRC, advanced stage disease or precursor lesions.

Results

Of the 62,554 FIT-positive participants, 53,171 (85%) received an OC and were eligible for analysis (median age 63.7 years, 56% men). In this group, 3,639 cancers were registered, 2,890 of which were registered with a defined stage of disease (79%), and 1,042 (36%) of these were advanced stage (UICC III & IV). In addition, 17,732 high-risk and 10,605 low-risk adenomas were identified. Compared to participants receiving the conclusive examination within 30 days, those receiving the examination more than 90 days after initial invitation were 3.49 times more likely to be diagnosed with any CRC (OR 3.49 [95% CI, 3.13–3.89]) and 2.10 times more likely to have advanced stage disease (OR 2.10 [95% CI, 1.73–2.56]). Those waiting for the longest were also more likely to have one or more high-risk adenomas (OR 1.59 [95% CI, 1.50–1.68]).

Conclusion

Increased screening response time was associated with a higher probability of detecting high-risk adenomas, any stage CRC and advanced stage cancer. More research is needed to explain what causes these associations.

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.

Bowel preparation quality scales for colonoscopy

Colorectal cancer (CRC) is the third most common cancer and second leading cause of cancer-related death in the United States. Colonoscopy is widely preferred for CRC screening and is the most commonly used method in the United States. Adequate bowel preparation is essential for successful colonoscopy CRC screening. However, up to one-quarter of colonoscopies are associated with inadequate bowel preparation, which may result in reduced polyp and adenoma detection rates, unsuccessful screens, and an increased likelihood of repeat procedure. In addition, standardized criteria and assessment scales for bowel preparation quality are lacking. While several bowel preparation quality scales are referred to in the literature, these differ greatly in grading methodology and categorization criteria. Published reliability and validity data are available for five bowel preparation quality assessment scales, which vary in several key attributes. However, clinicians and researchers continue to use a variety of bowel preparation quality measures, including nonvalidated scales, leading to potential confusion and difficulty when comparing quality results among clinicians and across clinical trials. Optimal clinical criteria for bowel preparation quality remain controversial. The use of validated bowel preparation quality scales with stringent but simple scoring criteria would help clarify clinical trial data as well as the performance of colonoscopy in clinical practice related to quality measurements.

Bowel preparation quality scales for colonoscopy

Colorectal cancer (CRC) is the third most common cancer and second leading cause of cancer-related death in the United States. Colonoscopy is widely preferred for CRC screening and is the most commonly used method in the United States. Adequate bowel preparation is essential for successful colonoscopy CRC screening. However, up to one-quarter of colonoscopies are associated with inadequate bowel preparation, which may result in reduced polyp and adenoma detection rates, unsuccessful screens, and an increased likelihood of repeat procedure. In addition, standardized criteria and assessment scales for bowel preparation quality are lacking. While several bowel preparation quality scales are referred to in the literature, these differ greatly in grading methodology and categorization criteria. Published reliability and validity data are available for five bowel preparation quality assessment scales, which vary in several key attributes. However, clinicians and researchers continue to use a variety of bowel preparation quality measures, including nonvalidated scales, leading to potential confusion and difficulty when comparing quality results among clinicians and across clinical trials. Optimal clinical criteria for bowel preparation quality remain controversial. The use of validated bowel preparation quality scales with stringent but simple scoring criteria would help clarify clinical trial data as well as the performance of colonoscopy in clinical practice related to quality measurements.

Difference in real-time magnetic image analysis of colonic looping patterns between males and females undergoing diagnostic colonoscopy

Background and study aim Magnetic imaging technology is of proven benefit to trainees in colonoscopy, but few studies have examined its benefits in experienced hands. There is evidence that colonoscopy is more difficult in women. We set out to investigate (i) associations between the looping configurations in the proximal and distal colon and (ii) differences in the looping prevalence between the sexes. We have examined their significance in terms of segmental intubation times and position changes required for the completion of colonoscopy.

Patients and methods We analyzed 103 consecutive synchronized luminal and magnetic image videos of diagnostic colonoscopies with normal anatomy undertaken by a single experienced operator.

Results Deep transverse loops and sigmoid N-loops were more common in females. A deep transverse loop was more likely to be present if a sigmoid alpha-loop or N-loop had formed previously. Patients with sigmoid N-loops were turned more frequently from left lateral to supine before the sigmoid-descending junction was reached, but there was no statistical correlation between completion time and looping pattern.

Conclusions This study has reexamined the prevalence of the common looping patterns encountered during colonoscopy and has identified differences between the sexes. This finding may offer an explanation as to why colonoscopy has been shown to be more difficult in females. Although a deep transverse loop following a resolved sigmoid alpha-loop was the most commonly encountered pattern, no statistical correlation between completion time and looping pattern could be shown. It is the first study to examine segmental completion times using a magnetic imager in expert hands.

Double-Balloon Endoscopy after Incomplete Colonoscopy and Its Comparison with Computed Tomography Colonography

BACKGROUND/AIMS

Because of the national screening program for colorectal carcinoma in The Netherlands, the number of colonoscopies has increased. In case of incomplete colonoscopy, computed tomography colonography (CTC) and double-balloon colonoscopy (DBc) are alternative options. This study evaluated cecal intubation rate and pathology detection rate in the previously unexplored part of the colon, complication rate of DBc, and CTC results after incomplete colonoscopy.

METHODS

Retrospective observational study in a tertiary referral hospital regarding DBc and CTC reports from cases with incomplete colonoscopy.

RESULTS

Sixty-three DBcs were performed after incomplete colonoscopy. Cecal intubation rate was 95%. Detection rate was 58% (5% carcinoma and 3% high-grade dysplastic adenoma). CTC preceded 54% of DBcs and 62% of CTC findings were confirmed. In 16%, a biopsy was taken, and in 60%, an intervention (mostly polypectomy) was performed. One major complication (1.5%) occurred, i.e., arterial bleeding due to polypectomy necessitating right hemicolectomy. CTC (n=213) showed a possible lesion in 35%, and could be confirmed by follow-up endoscopy or surgery in 65%.

CONCLUSIONS

DBc is effective and safe for completion of colon inspection in incomplete colonoscopy. In patients with a high likelihood of pathology, DBc is preferred over CTC.

Clinical Value of CT Colonography Versus Preoperative Colonoscopy in the Surgical Management of Occlusive Colorectal Cancer

OBJECTIVE

CT colonography (CTC) has been recognized as a complementary approach to evaluating the entire colon after incomplete colonoscopy (IC) in patients with occlusive colorectal cancer (CRC). The objective of this study is to evaluate changes in preoperative surgical planning after CTC is performed for patients with occlusive CRC and IC in an oncologic hospital.

MATERIALS AND METHODS

This retrospective study included 65 consecutive patients with occlusive CRC who underwent CTC after IC at our institution from February 2000 to April 2016. CTC examinations and radiology reports were reviewed by an abdominal radiologist. Clinical information was obtained from a review of the electronic medical record.

RESULTS

CTC contributed to a change in the initial surgical plan of the surgeon for 14 of 65 patients (21.5%). In these 14 patients, CTC detected five synchronous proximal colon polyps (35.7%), five synchronous proximal cancers (35.7%), two imprecise CRC locations (14.3%), one case of proximal colon ischemia (7.1%), and one instance of tumor infiltration of the urinary bladder (7.1%). All CTC findings were confirmed at surgery, and all proximal colon polyps were subsequently confirmed to be advanced adenomas.

CONCLUSION

The preoperative CTC findings optimized the surgical management plan for 21.5% of patients with occlusive CRC and IC.

Occult Spigelian Hernia Presenting as Inability to Complete Colon Cancer Screening in a Patient with a History of Rectal Cancer

Patient: Male, 62

Final Diagnosis: Spigelian hernia

Symptoms: Abdominal discomfort

Medication: —

Clinical Procedure: Hernia repair and colonoscopy

Specialty: Gastroenterology and Hepatology

Double-Balloon Colonoscopy Has a Higher Cecal Intubation Rate Than Conventional Colonoscopy Using a Colon Simulator

BACKGROUND/AIM

Cecal intubation using conventional colonoscopy (CC) requires substantial training. We hypothesized that double-balloon colonoscopy (DBC) facilitates cecal intubation by endoscopy naïve operators. The aim of this study is to evaluate the cecal intubation rate and learning curve of DBC compared with CC.

METHODS

Eighteen endoscopy naïve medical students were allocated to two groups and attempted cecal intubation within 20 min using a colon simulator. In group A, CC was performed ten times and then DBC ten times. In group B, the reverse was carried out. We evaluated the cecal intubation rate and learning curve.

RESULTS

The overall success rate for cecal intubation using DBC was significantly superior to CC [132/180 (73%) vs. 12/180 (7%), p < 0.001]. To evaluate the success rate overtime, we divided the ten repetitions of the procedure into three time periods: first (1-3), second (4-6), and third (7-10). The success rate using CC is <20%, even during the third time period, in both groups, and one perforation occurred. The success rate using DBC is over 30% in the first period and increased to nearly 80% in the third period in both groups. Finally, we evaluated the time needed for cecal intubation using DBC. The mean cecal intubation time in the first period is 14 min and decreased to 11 min in the third period.

CONCLUSIONS

DBC has a higher cecal intubation rate than CC performed by endoscopy naïve medical students using a colon simulator in this randomized-controlled, cross-over study.

Prospective study of factors important to achieve observation of the entire colon on colon capsule endoscopy

BACKGROUND

Colon capsule endoscopy (CCE) is a procedure in which capsule swallowing facilitates observation of the lumen of the entire digestive tract. It does not require an air supply, and is a noninvasive procedure with a markedly low risk of adverse events in comparison with conventional colonoscopy (CS). It reduces patient stress, and may be acceptable to patients. A limitation of this procedure is that the entire colon observation rate (CCE excretion rate, completed CCE rate) is not 100%. In this study, we prospectively investigated clinical factors important to achieve observation of the entire colon on CCE.

METHODS

The participants were 70 patients for whom CCE was scheduled, and from whom written informed consent regarding participation in this study was obtained. We selected patient background/examination factors, and analyzed all factors involved in observation of the entire colon and factors for completion of the CCE within 4 h after the start of examination using multivariate analysis.

RESULTS

Of the 70 enrolled patients, 64 were analyzed, excluding 6. On multiple logistic analysis, only a water intake of ⩾12.0 ml/min during examination [p = 0.025, odds ratio (OR): 46.753, 95% confidence interval (CI): 1.630-1341.248] was identified as an independent predictive factor involved in observation of the entire colon. With respect to factors involved in the completion of CCE within 4 h, multiple logistic analysis showed that a body mass index (BMI) of ⩾25 (p = 0.039, OR: 13.723, 95% CI: 1.135-165.913), the absence of constipation (p = 0.030, OR: 13.988, 95% CI: 1.287-152.047), and a water intake of ⩾12.0 ml/min during examination (p = 0.004, OR: 12.028, 95% CI: 2.225-65.029) were independent predictive factors.

CONCLUSIONS

Completion of a CCE was most closely related to water intake per hour. In addition to water intake, CCE-promoting factors included a high BMI and the absence of constipation.

MR colonography with a fecal tagging technique and water-based enema for the assessment of inflammatory bowel disease

PURPOSE

To assess the usefulness of MR colonography (MRC) with a fecal tagging technique and water-based enema in patients with inflammatory bowel disease (IBD).

MATERIALS AND METHODS

Twenty-two patients with suspected or known IBD underwent MRC with a 1.5-T MR system (Siemens Symphony) using a phased-array coil. A fecal tagging technique was performed by oral administration of dense barium sulfate (200 ml) at major meals starting 2 days before the MRI. After a water enema (2000-2500 ml), the MR protocol was carried out, starting with HASTE and true-FISP sequences. Coronal T1w 3D VIBE (2.0 mm thick) was obtained before and 60 s after intravenous administration of Gd chelate. MR images were evaluated by consensus agreement of two observers in terms of image quality and by searching for bowel abnormalities. MRC findings were correlated with our gold standard-conventional colonoscopy (incomplete in 6/22 patients) with histopathological analysis, and surgery (performed in 8/22 subjects).

RESULTS

The MR imaging protocol was completed in all of the investigated subjects. In terms of image quality, 128 out of 132 colon segments (97 %) were considered diagnostic on MR examinations by the two reviewers; signs of bowel inflammation were identified in 74 and 72 % of colon segments of patients with ulcerative colitis (n = 6) and Crohn's disease (n = 15), respectively. In 13/15 patients with Crohn's disease, involvement of both the large and small bowel was demonstrated on MR imaging; perianal abscesses and fistulas were also identified in 2 and 3 of these patients, respectively. In one patient with normal MRC, a diagnosis of IBD could not be confirmed.

CONCLUSION

MRC with a fecal tagging technique and water-based enema is a promising minimally invasive technique for evaluating the bowel in patients with a suspected or established diagnosis of IBD.

The Current Role of Radiologic and Endoscopic Imaging in the Diagnosis and Follow-Up of Colonic Diverticular Disease. AJR Am J Roentgenol. 2016;207:15-24. [PMID: 27082846 DOI: 10.2214/ajr.16.16138]

OBJECTIVE

Colonic diverticular disease is among the most prevalent conditions in Western society and is a common cause for outpatient visits and hospitalizations. The role of imaging is in evolution, but it has proven useful in confirming clinically suspected disease, assessing severity and complications, and directing patient management.

CONCLUSION

This review focuses on the current role of radiologic and endoscopic imaging in distinct clinical scenarios of diverticular disease, with emphasis on diverticulitis and its follow-up.

Complete colonoscopy: impact of patients' demographics and anthropometry on caecal intubation time

Background and aim

Factors that affect caecal intubation during colonoscopy include age and sex of the patient, quality of bowel preparation, prior abdominal or pelvic surgery and pelvic inflammatory disease, among others. The aim of this prospective study was to evaluate the effects of patients' demography such as age and sex, as well as anthropometry (height, weight and body mass index (BMI)) on caecal intubation time (CIT).

Patients and methods

All consecutive patients referred for colonoscopy over a period of 6 months were recruited into the study. Prior to the procedure, patients' demographic data as well as history of prior abdominal or pelvic surgery were recorded. The height and weight of each patient were taken, and the BMI calculated. CIT was measured from the time of insertion of the colonoscope into the anal canal to the time when the base of the caecum was intubated.

Results

A total of 167 patients comprising 99 (59.3%) males and 68 (40.7%) females were studied. The mean CIT of the procedures was 912.5±477.1 s with a range of 180–3180 s. It was more prolonged in patients older than 65 years of age, in males and in those with prior abdominal/pelvic surgery, although no significant difference was observed among the groups. Multivariate logistic regression analysis showed that increased BMI and non-usage of additional manoeuvres independently reduced CIT.

Conclusions

Older age, male gender, prior abdominal/pelvic surgery, use of additional manoeuvres and lower BMI were found to prolong CIT.

Impact of Intestinal Ultrasound on Classification and Management of Crohn's Disease Patients with Inconclusive Colonoscopy

Background and Aims. We aim to evaluate the benefit of ultrasound in the assessment of Crohn's disease and to demonstrate its potential contribution to disease management. Methods. We conduct a retrospective review of adult patients with Crohn's disease examined with sonography and colonoscopy within 30 days. Study patients were identified in whom colonoscopy did not access a pathological segment, detected and evaluated by ultrasonography. Changes in management were predominantly attributed to ultrasound in those cases where the diseased segment was not assessed on endoscopy. Results. From 115 patients with temporally related ileocolonoscopy and ultrasound, 41 had disease fully assessed on ultrasound only, with complications in 26/41. Twenty-nine of 41 had mild or no endoscopic inflammation with moderate or severe disease on ultrasound at the same segment or at a segment proximal to the reach of the endoscope. Changes in management were significantly attributed to ultrasound in 22 of these 29 patients. Conclusion. The benefit of cross-sectional imaging is invaluable for the comprehensive assessment of bowel not shown on ileocolonoscopy. Ultrasound may make a significant contribution to correct classification of disease extent and severity of Crohn's disease. Prospective studies are needed to further understand the contribution of US in patient management.

When and why a colonoscopist should discontinue colonoscopy by himself?

AIM: To investigate when and why a colonoscopist should discontinue incomplete colonoscopy by himself.

METHODS: In this cross-sectional study, 517 difficult colonoscope insertions (Grade C, Kudo’s difficulty classification) screened from 37800 colonoscopy insertions were collected from April 2004 to June 2014 by three 4^th-level (Kudo’s classification) colonoscopists. The following common factors for the incomplete insertion were excluded: structural obstruction of the colon or rectum, insufficient colon cleansing, discontinuation due to patient’s discomfort or pain, severe colon disease with a perforation risk (e.g., severe ischemic colonopathy). All the excluded patients were re-scheduled if permission was obtained from the patients whose intubation had failed. If the repeat intubations were still a failure because of the difficult operative techniques, those patients were also included in this study. The patient’s age, sex, anesthesia and colonoscope type were recorded before colonoscopy. During the colonoscopic examination, the influencing factors of fixation, tortuosity, laxity and redundancy of the colon were assessed, and the insertion time (> 10 min or ≤ 10 min) were registered. The insertion time was analyzed by t-test, and other factors were analyzed by univariate and multivariate logistic regression.

RESULTS: Three hundred and twenty-two (62.3%) of the 517 insertions were complete in the colonoscope insertion into the ileocecum, but 195 (37.7%) failed in the insertion. Fixation, tortuosity, laxity or redundancy occurred during the colonoscopic examination. Multivariate logistic regression analysis revealed that fixation (OR = 0.06, 95%CI: 0.03-0.16, P < 0.001) and tortuosity (OR = 0.04, 95%CI: 0.02-0.08, P < 0.001) were significantly related to the insertion into the ileocecum in the left hemicolon; multivariate logistic regression analysis also revealed that fixation (OR = 0.16, 95%CI: 0.06-0.39, P < 0.001), tortuosity (OR 0.23, 95%CI: 0.13-0.43, P < 0.001), redundancy (OR = 0.12, 95%CI: 0.05-0.26, P < 0.001) and sex (OR = 0.35, 95%CI: 0.20-0.63, P < 0.001) were significantly related to the insertion into the ileocecum in the right hemicolon. Prolonged insertion time (> 10 min) was an unfavorable factor for the insertion into the ileocecum.

CONCLUSION: Colonoscopy should be discontinued if freedom of the colonoscope body’s insertion and rotation is completely lost, and the insertion time is prolonged over 30 min.