Incomplete Optical Colonoscopy Research Articles

Computed tomography colonography and radiation risk: How low can we go?

Computed tomography colonography (CTC) has become a key examination in detecting colonic polyps and colorectal carcinoma (CRC). It is particularly useful after incomplete optical colonoscopy (OC) for patients with sedation risks and patients anxious about the risks or potential discomfort associated with OC. CTC's main advantages compared with OC are its non-invasive nature, better patient compliance, and the ability to assess the extracolonic disease. Despite these advantages, ionizing radiation remains the most significant burden of CTC. This opinion review comprehensively addresses the radiation risk of CTC, incorporating imaging technology refinements such as automatic tube current modulation, filtered back projections, lowering the tube voltage, and iterative reconstructions as tools for optimizing low and ultra-low dose protocols of CTC. Future perspectives arise from integrating artificial intelligence in computed tomography machines for the screening of CRC.

Intestinal malrotation in adults: prevalence and findings based on CT colonography.

Intestinal malrotation is largely a pediatric diagnosis, but initial detection can be made in adulthood. CT colonography (CTC) provides an ideal means for estimating prevalence. Our purpose was to evaluate the prevalence and imaging findings of intestinal malrotation in asymptomatic adults at CTC screening, as well as incomplete optical colonoscopy (OC) referral. The CTC database of a single academic institution was searched for cases of intestinal malrotation (developmental nonrotation). Prevalence was estimated from 11,176 adults undergoing CTC. Demographic, clinical, imaging (CTC and other abdominal exams), and surgical data were reviewed. 27 cases of malrotation were confirmed (mean age 62 ± 9years; 15M/12F), including 17 from the CTC screening cohort (0.17% prevalence) and 10 from incomplete OC (0.75% prevalence; p < 0.001). Most cases (59%; 16/27) were initially diagnosed at CTC. In 67% (12/18); the presence of malrotation was missed on at least one relevant abdominal imaging examination. At least 22% (6/27) had a history of unexplained, chronic intermittent abdominal pain. At CTC, the SMA-SMV relationship was normal in only 11% (3/27). The ileocecal valve was located in the RLQ in only 22% (6/27). Two patients (7%) had associated findings of heterotaxy (polysplenia). The prevalence of intestinal malrotation was four times greater for patients referred from incomplete OC compared with primary screening CTC, likely related to anatomic challenges at endoscopy. Malrotation was frequently missed at other abdominal imaging examinations. CTC can uncover unexpected cases of malrotation in adults, which may be relevant in terms of potential for future complications.

PET/CT Integrated With CT Colonography in Preoperative Obstructive Colorectal Cancer by Incomplete Optical Colonoscopy: A Prospective Study.

The aim of this study was to evaluate if integrating whole-body PET/CT with CT colonography (PET/CTC) improves the preoperative diagnosis of obstructive colorectal cancer (CRC). We prospectively included 47 consecutive patients (18 women and 29 men; mean age, 71 ± 14 years) suspected of having CRC by optical colonoscopy, which was not completed due to obstructive masses. To perform PET/CTC, a small caliber Foley catheter was inserted to distend the colon with CO2 insufflations. Polyps measuring 10 mm or larger were considered as high risk of malignancy. All findings were histologically confirmed. Colorectal cancer was localized in the sigmoid (n = 21), rectum (n = 7), rectosigmoid junction (n = 5), ascending (n = 7), descending (n = 5), and transverse (n = 2) colon. All tumors showed FDG uptake (mean ± SD SUVmax, 20.02 ± 9.9) including one synchronic tumor (SUVmax, 10.46). Forty-seven polyps were histologically confirmed as smaller than 10 mm (n = 35) and 10 mm or larger (n = 12). All 12 polyps 10 mm or larger showed FDG uptake (SUVmax range, 3.08-19.5), but only one smaller than 10 mm could be identified by PET. Pathological lymph nodes were diagnosed in 17/47 cases after surgical removal with a sensitivity and specificity for CTC and PET/CTC of 71% and 97% and 59% and 100%, respectively. Liver metastases were confirmed in 9 patients and in 4/9 along with lung metastases (n = 2) or implants (n = 2), showing a sensitivity and specificity for CTC of 89% and 100% and both 100% for PET/CTC. PET/CTC is a reliable technique for staging CRC and diagnosing synchronous tumors. In this series, PET/CTC was not able to identify small polyps but showed potential use for ruling out 10 mm or larger polyps at high risk of malignancy.

Quality of same-day CT colonography following incomplete optical colonoscopy.

Same-day CT colonography (CTC) following incomplete optical colonoscopy allows patients to avoid both a delayed diagnosis and the need for repeat bowel preparation. The aim of our study is to establish the diagnostic quality of same-day CT colonography following an incomplete optical colonoscopy. We performed a retrospective review of patients undergoing same-day CT colonography following an incomplete colonoscopy at our center between July 2015 and December 2017 (N= 245). We divided the large bowel into thirteen subsegments in each patient. Using a semiquantitative scoring system, the quality of bowel preparation, adequacy of fecal tagging, and luminal distension were assessed in each subsegment on all views performed. A combined score for each subsection was obtained. Ninety-nine percent of studies did not require a repeat CTC or optical colonoscopy. Median values for bowel preparation and fecal tagging were satisfactory across the bowel segments for the cohort and luminal distension was acceptable in all but three patients. Same-day CTC should be considered in centers with capacity, following an incomplete optical colonoscopy. Same-day completion CTCs are of high diagnostic quality and this approach allows patients to avoid repeat bowel cleansing or a delayed diagnosis. • Same-day CT colonography is a high-quality examination that can be performed following incomplete optical colonoscopy. • Same-day CT colonography should be considered for patients with incomplete optical colonoscopy in centers with the capacity to offer this service. • Same-day CTC can avoid a delay in diagnosis and avoids repeat bowel preparation.

Same-day colon capsule endoscopy is a viable means to assess unexplored colonic segments after incomplete colonoscopy in selected patients.

Same-day colon capsule endoscopy (CCE) immediately following incomplete optical colonoscopy (OC) would have a number of advantages for patients, while also presenting unique procedural challenges including the effect of sedation on capsule propulsion and patient tolerance of protracted preparation and fasting. The aim of this article is to prospectively assess the efficacy of same-day CCE after incomplete OC in an unselected patient cohort. This was an observational, prospective, single-centre study of CCE post-incomplete colonoscopies. Patients with an incomplete OC for any reason other than obstruction or inadequate bowel preparation were recruited. CCE was performed after a minimum of a one-hour fast. Once the patient was fully alert, intravenous metoclopramide was administered after capsule ingestion when possible, and a standard CCE booster protocol was then followed. Relevant clinical information was recorded. CCE completion rates, findings and their impact, and adverse events were noted. Fifty patients were recruited, mean age = 57 years and 66% (n = 32) were female. Seventy-six per cent (n = 38) of CCEs were complete; however, full colonic views were obtained in 84% (n = 42) of cases. Patients > 50 years of age were five times more likely to have an incomplete CCE and there was also a trend towards known comorbidities associated with hypomobility having reduced excretion rates. Overall diagnostic yield for CCE in the unexplored segments was 74% (n = 37), with 26% (n = 13) of patients requiring significant changes in management based on CCE findings. The overall incremental yield was 38%. CCE findings were normal 26% (n = 13), polyps 38% (n = 19), inflammation 22% (n = 11), diverticular disease 25 (n = 12), angiodysplasia 3% (n = 1) and cancer 3% (n = 1). Significant small bowel findings were found in three (6%) cases, including Crohn's disease and a neuroendocrine tumour. A major adverse event occurred in one patient (2%), related to capsule retention. Same-day CCE is a viable alternative means to assess unexplored segments of the colon after incomplete OC in selected patients.

PillCamColon2 after incomplete colonoscopy - A prospective multicenter study

AIMTo evaluate the ability of PillCamColon2 to visualize colonic segments missed by incomplete optical colonoscopy (OC) and to assess the diagnostic yield.METHODSThis 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.RESULTSSeventy-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.CONCLUSIONSecond-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.

CT colonography: implementation, indications, and technical performance – a follow-up national survey

Computed tomography colonography (CTC) is an accepted complement or alternative to optical colonoscopy (OC) but its implementation is incompletely analyzed, and technical performance varies between centers. To evaluate implementation, indications, and technical performance of CTC in Sweden and to evaluate compliance to international guidelines. A structured, self-assessed questionnaire regarding implementation and technical performance of CTC was sent to all eligible radiology departments in Sweden. Eighty-six out of 89 departments replied. Comparisons were made with similar national surveys from 2004 and 2009. The number of centers performing CTC gradually increased from 23 in 2004 to 77 in 2016. In parallel, centers performing barium enema (BE) examinations have decreased from 89 in 2004 to 13 in 2016. Main reasons stated for still performing BE were lack of resources regarding CTC/OC. Main reasons for not performing CTC were lack of suitable software, lack of machine/reading time, and lack of experience. The majority of centers follow international CTC guidelines. An important exception is fecal tagging, which was implemented in only 63% of the centers. Incomplete OC remains a major indication for CTC, while preoperative CTC in colorectal cancer and follow-up after diverticulitis have emerged as new indications. CTC today is well implemented in routine healthcare but still lacking in capacity. Indications have expanded over time, and most departments perform "state of the art" CTC, although fecal tagging is incompletely implemented.

Differences between genders in colorectal morphology on CT colonography using a quantitative approach: a pilot study

PurposeTo explore quantitative differences between genders in morphologic colonic metrics and determine metric reproducibility. MethodsQuantitative colonic metrics from 20 male and 20 female CTC datasets were evaluated twice by two readers; all exams were performed after incomplete optical colonoscopy. Intra−/inter-reader reliability was measured with intraclass correlation coefficient (ICC) and concordance correlation coefficient (CCC). ResultsWomen had overall decreased colonic volume, increased tortuosity and compactness and lower sigmoid apex height on CTC compared to men (p<0.0001,all). Quantitative measurements in colonic metrics were highly reproducible (ICC=0.9989 and 0.9970; CCC=0.9945). ConclusionQuantitative morphologic differences between genders can be reproducibility measured.

Přínos CT kolografie v klinické praxi

CT colonography is a CT examination focused on the detection of colonic polyps and masses. Its most common indications include incomplete optical colonoscopy and generally personal preference in symptomatic or frail patients. CT colonography has a diagnostic yield similar to optical colonoscopy. It is less demanding for the patient, has shorter examination times, lower rates of adverse effects (including bowel perforation) and allows limited evaluation of extracolonic structures. In 10-15 % of asymptomatic patients, optical colonoscopy is needed if either a colonic polyp or mass is detected. CT colonography requires bowel prior preparation, including laxatives and stool tagging with contrast material. Stool tagging can be completed for same-day CT colonography after an incomplete colonoscopy. Evaluation of extracolonic structures in CT colonography is limited, but CT colonography can be combined with other CT examinations (eg. CT of abdomen). C-RADS classification has been established for a more straightforward interpretation of findings on CT colonography. CT colonography and optical colonoscopy complement each other but do not compete.Key words: colonoscopy - colorectal carcinoma - CT colonography - polyp - screening - virtual colonoscopy.

Diagnostic value of computed tomography colonography (CTC) after incomplete optical colonoscopy

IntroductionThis study evaluated the role of computed tomography colonography (CTC) in patients who previously underwent incomplete optical colonoscopy (OC). We analyzed the impact of colonic lesions in intestinal segments not studied by OC and extracolonic findings in these patients. MethodsBetween January 2014 and May 2015, 61 patients with a history of abdominal pain and incomplete OC examination were studied by CTC. CTCs were performed by 320-row CT scan in both the supine and the prone position, without intravenous administration of contrast medium. In all patients both colonic findings and extracolonic findings were evaluated. ResultsAmong the study group, 24 CTC examinations were negative for both colonic and extracolonic findings while 6 examinations revealed the presence of both colonic and extracolonic findings. In 24 patients CTC depicted colonic anomalies without extracolonic ones, while in 7 patients it showed extracolonic findings without colonic ones. DiscussionCTC is a noninvasive imaging technique with the advantages of high diagnostic performance, rapid data acquisition, minimal patient discomfort, lack of need for sedation, and virtually no recovery time. CTC accurately allows the evaluation of the nonvisualized part of the colon after incomplete OC and has the distinct advantage to detect clinically important extracolonic findings in patients with incomplete OC potentially explaining the patient's symptoms and conditioning their therapeutic management. ConclusionCTC accurately allows the assessment of both colonic and extracolonic pathologies representing a useful diagnostic tool in patients for whom complete OC is not achievable.

Predictors of incomplete optical colonoscopy using computed tomographic colonography.

Background/Aims:Optical colonoscopy (OC) is the primary modality for investigation of colonic pathology. Although there is data on demographic factors for incomplete OC, paucity of data exists for anatomic variables that are associated with an incomplete OC. These anatomic variables can be visualized using computed tomographic colonography (CTC). We aim to retrospectively identify variables associated with incomplete OC using CTC and develop a scoring method to predict the outcome of OC.Patients and Methods:In this case–control study, 70 cases (with incomplete OC) and 70 controls (with complete OC) were identified. CTC images of cases and controls were independently reviewed by a single CTC radiologist. Demographic and anatomical parameters were recorded. Data was examined using descriptive linear statistics and multivariate logistic regression model.Results:On analysis, female gender (80% vs 58.6% P = 0.007), prior abdominal/pelvic surgeries (51.4% vs 14.3% P < 0.001), colonic length (187.6 ± 30.0 cm vs 163.8 ± 27.2 cm P < 0.001), and number of flexures (11.4 ± 3.1 vs 8.4 ± 2.9 P < 0.001) increased the risk for incomplete OC. No significant association was observed for increasing age (P = 0.881) and history of severe diverticulosis (P = 0.867) with incomplete OC. A scoring system to predict the outcome of OC is proposed based on CTC findings.Conclusion:Female gender, prior surgery, and increasing colonic length and tortuosity were associated with incomplete OC, whereas increasing age and history of severe diverticulosis were not. These factors may be used in the future to predict those patients who are at risk of incomplete OC.

CT colonography after incomplete optical colonoscopy: bowel preparation quality at same-day vs. deferred examination.

To objectively compare the volume, density, and distribution of luminal fluid for same-day oral-contrast-enhanced CTC following incomplete optical colonoscopy (OC) vs. deferred CTC on a separate day utilizing a dedicated CTC bowel preparation. HIPAA-compliant, IRB-approved retrospective study compared 103 same-day CTC studies after incomplete OC (utilizing 30 mL oral diatrizoate) against 151 CTC examinations performed on a separate day after failed OC using a dedicated CTC bowel preparation (oral magnesium citrate/dilute barium/diatrizoate the evening before). A subgroup of 15 patients who had both same-day CTC and separate-day routine CTC was also identified and underwent separate analysis. CTC exams were analyzed for opacified fluid distribution within the GI tract, as well as density and volume. Data were analyzed utilizing Kruskal-Wallis and Wilcoxon Signed Rank tests. Opacified luminal fluid extended to the rectum in 56% (58/103) of same-day CTC vs. 100% (151/151) of deferred separate-day CTC (p < 0.0001). For same-day CTC, contrast failed to reach the colon in 11% (11/103) and failed to reach the left colon in 26% (27/103). Volumetric colonic fluid segmentation for fluid analysis (successful in 80 same-day and 147 separate-day cases) showed significantly more fluid in the same-day cohort (mean, 227 vs. 166 mL; p < 0.0001); the actual difference is underestimated due to excluded cases. Mean colonic fluid attenuation was significantly lower in the same-day cohort (545 vs. 735 HU; p < 0.0001). Similar findings were identified in the smaller cohort with direct intra-patient CTC comparison. Dedicated CTC bowel preparation on a separate day following incomplete OC results in a much higher quality examination compared with same-day CTC.

The safety of same-day CT colonography following incomplete colonoscopy with polypectomy.

Concerns about the risk of bowel perforation for same-day computed tomography colonography (CTC) following an incomplete colonoscopy with polypectomy may lead to unnecessarily postponing the CTC. The objective of this article is to describe the complications including colon perforations associated with same-day CTC in a cohort who had polypectomies but an incomplete colonoscopy. We conducted a retrospective study. Our study took place in a single, tertiary referral center. We studied consecutive patients who had CTC the same day as an incomplete colonoscopy with polypectomy. Interventions included optical colonoscopy (OC), endoscopic polypectomies, and same-day CTC. Our main outcome measurements included perforation rate with long-term follow-up. A total of 3% of patients undergoing colonoscopy from January 2008 to December 2012 had same-day CTC following incomplete OC, and 72 polypectomies were performed in 34 (or 17%) of these patients. Incomplete colonoscopies were due to colon tortuosity and looping (25), severe angulations (five), colon mass (two), colon stenosis (one), bradycardia (one). Fifty-three percent of the OCs were screening for colon neoplasia, 29% diagnostic and 18% were surveillance of colon polyps. Most polyps were ≤ 5 mm, and found in the left colon. There were no reported complications or perforations associated with same-day CTCs during short- and long-term follow-up. Limitations of our analysis included retrospective single-center design, small number of patients for the occurrence, referral to same-day CTC was not standardized, inability to establish safety of CTC for specific scenarios such as after complex polypectomies, strictures, or advanced IBD. Radiologists' apprehension to perform a CTC the same day as an incomplete colonoscopy following polypectomies because of perceived risk of perforation may be unfounded. More data are needed to determine the safety of same-day CTC in patients with high-risk findings during colonoscopy such as a stricture, severe IBD, and after complex polypectomies.

Dual-Energy CT Colonography for Preoperative “One-Stop” Staging in Patients with Colonic Neoplasia

To evaluate the benefits of dual-energy computed tomography (CT) colonography (DECTC) as a preoperative staging tool in patients with clinically suspected colorectal cancer (CRC). Twenty-two patients with colorectal neoplasia underwent preoperative abdominal DECTC on a dual-source scanner (SOMATOM Definition Flash; Siemens) operated at tube potentials of Sn140/100 kVp. Scans were evaluated for local tumor stage and the presence of synchronous intracolonic and extracolonic findings using dual-energy color-coded images. An enhancement ≥25 Hounsfield units (HU) was defined to indicate malignancy. Patients' effective doses were calculated. Preoperative DECTC allowed for complete bowel evaluation in all patients, including subjects with stenosing CRC. DECTC revealed 22 carcinomas (mean enhancement, 47±12 HU). In total, 22 synchronous intracolonic lesions were detected, including 19 adenomas (meanenhancement, 51±19 HU). Benign structures showed enhancement <25 HU. Comparing DECTC to histopathology, 95% carcinomas and 71% synchronous lesions proximal to stenosing CRC could be verified. Mean estimated effective dose was 13.0±5.2mSv. Preoperative DECTC can be used as an accurate and dose-efficient primary-staging examination. Especially after incomplete optical colonoscopy, virtual colonoscopy enables full preoperative colonic assessment on the same day. Dual-energy CT enables distinction between neoplasia and non-neoplastic findings within and outside the colon. Therefore, DECTC can be regarded as a promising "one-stop" staging examination in patients with clinically suspected CRC.

The Modified Mayo Clinic technique: Emphasis on plausible significant reduction of colon cancer.

To compare the ability to detect colonic polyps using a modified Mayo Clinic (MMC) barium enema technique with that of the usual gold standard optical colonoscopy (OC). Patients considered at an average or increased risk of colorectal cancer were initially screened using the MMC technique. Patients who refused OC, those who had isolated rectal lesions and those with incomplete OC were excluded. Patients with mass lesions in the right colon or left colon were further assessed using OC. A total of 142 consecutive patients were examined using the MMC technique. Of these, 18 patients were found to have mass lesions in the right or left colon and were further evaluated using OC. Sensitivity and specificity of the MMC technique for detecting colonic polyps/cancers of ≥ 0.3 cm were 87.5% and 80.0%, respectively. Most significantly, for detecting polyps of ≥ 1.0 cm, the false-negative rate was 0%. The MMC technique may provide an alternative screening method to OC for the detection of colorectal polyps, particularly in countries where resources are scarce.

Virtual Colonoscopy is Feasible in Geriatric Patients-A Case Series

Virtual colonoscopy (VC) or computed tomographic colonography is now an established imaging test in the detection of colorectal cancer. Like other modern imaging tests VC requires highly compliant patients (rectal air insufflation, breath hold, imaging in supine and prone position). As patients are getting older VC is also requested in the elderly. In a case series of geriatric patients (mean age 83 years) undergoing VC after incomplete optical colonoscopy 92.7% of all colonic segments were adequately visualized. VC seems to be feasible in geriatric patients and has therefore replaced barium enema in this patient group after incomplete optical colonoscopy at our department.

Predictors of CT Colonography Utilization Among Asymptomatic Medicare Beneficiaries

Although the Centers for Medicare and Medicaid Services (CMS) denied coverage for screening computed tomography colonography (CTC) in March 2009, little is understood about whether CTC was targeted to the appropriate patient population prior to this decision. Evaluate patient characteristics and known relative clinical indications for screening CTC among patients who received CTC compared to optical colonoscopy (OC). Cross-sectional study of all 10,538 asymptomatic Medicare beneficiaries who underwent CTC between January 2007 and December 2008, compared to a cohort of 160,113 asymptomatic beneficiaries who underwent OC, matched on county of residence and year of examination. Patient characteristics and known relative appropriate and inappropriate clinical indications for screening CTC. CTC utilization was higher among women, patients > 65years of age, white patients, and those with household income > 75% (p = 0.001). Patients with relatively appropriate clinical indications for screening CTC were more likely to undergo CTC than OC including presumed incomplete OC (OR 80.7, 95 % CI 76.01-85.63); sedation risk (OR 1.11, 95 % CI 1.05-1.17); and chronic anticoagulation risk (OR 1.46, 95 % CI 1.38-1.54), after adjusting for patient characteristics and known clinical indications. Conversely, patients undergoing high-risk screening, an inappropriate indication, were less likely to receive CTC (OR 0.4, 95 % CI 0.37-0.42). Overall, 83% of asymptomatic patients referred to CTC had at least one clinical indication relatively appropriate for CTC (8,772/10,538). During the 2years preceding CMS denial for screening, CTC was targeted to asymptomatic patients with relatively appropriate clinical indications for CTC/not receiving OC. However, CTC utilization was lower among certain demographic groups, including minority patients. These findings raise the possibility that future coverage of screening CTC might exacerbate disparities in colorectal cancer screening while increasing overall screening rates.

Safety and Outcomes of Same-day CT Colonography After Incomplete Optical Colonoscopy - A Single Center Experience

Purpose: CT colonography has proven a useful tool to complete colon cancer screening in patients when optical colonoscopy fails. Performed on the same day, CT colonography obviates the need for a second bowel preparation and medical appointment. However, concern has been raised over the safety of performing back-to-back procedures given the need for a second air insufflation. The aim of this study was to evaluate the safety and outcome of same-day CT colonography after an incomplete colonoscopy at a community hospital. Methods: A retrospective analysis identified 244 consecutive patients who underwent CT colonography between June 2006 and May 2011 for colon cancer screening. Variables including patient demographics, test findings, and safety were evaluated in the cohort of patients who underwent same-day CT colonography for failed optical colonoscopy. Results: The total number of colonoscopies performed during the study interval was 30,741. There was one incomplete colonoscopy for every 232 performed. Following incomplete optical colonoscopy, 132 patients underwent same-day CT colonography. The study group was composed of 85 women and 47 men. The median age was 64. The most common indication for colonoscopy was colorectal cancer screening (49, 37%) followed by polyp surveillance (22, 17%). Prior abdominal surgeries were noted in 25 patients (19%). The most common reasons for an incomplete colonoscopy were bowel looping (52, 40%) and pain (26, 20%). The most frequent location of exam termination was at the splenic or hepatic flexures (23, 17% each). CT colonography revealed 3 polyps of greater than 10 mm, 23 polyps of 5 to 10 mm and 41 polyps of less than 5 mm. Thirty follow-up studies including colonoscopy and surgery with biopsy were performed and confirmed 4 tubular adenomas, one tubulovillous adenocarcinoma in situ with severe dysplasia and one adenocarcinoma. There were no bowel perforations or other complications reported and no patient required overnight admission. The most common extracolonic finding was renal calculi. Conclusion: Same-day CT colonography performed after incomplete optical colonoscopy is a safe strategy to complete colorectal cancer screening without requiring a second bowel preparation or medical visit.

Sa1580 Impact of Colon Capsule Endoscopy on Medical Decision Making in Patients With Incomplete Optical Colonoscopy

Sa1580 Impact of Colon Capsule Endoscopy on Medical Decision Making in Patients With Incomplete Optical Colonoscopy

Technical quality of CT colonography in relation with diverticular disease

The aim of the study is to explore how the technical quality of the examination was affected by diverticular disease. We retrospectively evaluated a consecutive series of 78 subjects who underwent CTC for screening (n=58) or staging (n=20) colorectal cancer, 38 of them (49%) after an incomplete optical colonoscopy. Patients were administered a mild laxative and a iodinated contrast material for fecal tagging. We scored both the bowel preparation and the overall colon distension as poor, good, or optimal and measured the mean sigmoid colon diameter. We counted the number of diverticula and classified patients as having or not a severe diverticular disease (SDD). The number of the prompts of computer aided diagnosis (CAD) per patient was also considered. Mann-Whitney U and χ(2) tests were performed. No CTC complications occurred. The bowel cleansing was poor in 8 (10%) patients, good in 29 (37%) and optimal in 41 (53%); colon distension was poor in 7 (9%) patients, good in 38 (49%), and optimal in 33 (42%). Fifty-four (69%) showed diverticula and 30 (38%) had an SDD. Bowel cleansing and distension were not significantly impaired by neither diverticula (p>0.590) nor the SDD (p>0.110). Mean sigmoid colon diameter was reduced in presence of diverticula (28 mm versus 23 mm, p=0.009) or SDD (26 mm versus 22 mm, p=0.016). The mean number of CAD prompts per patient was not significantly increased by the presence of SDD (p=0.829). Bowel cleansing and distension at CTC were not influenced by the presence of diverticular disease.