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Computed tomography colonography (CTC) is a safe and accurate tool for colorectal cancer (CRC) screening in both symptomatic and asymptomatic patients. CTC requires dedicated radiological expertise and demonstrates a high sensitivity and specificity in polyp detection, which is similar to optical colonoscopy (OC). Newer preparation techniques for CTC, such as faecal tagging without catharsis might further improve both the tolerability and accuracy of the test. While exposure to ionising radiation, lack of capacity for therapeutic intervention and potentially diminished sensitivity for flat serrated polyps are limitations of CTC, the technique has a role in select populations. CTC should be considered in frail or elderly patients at high anaesthetic risk for OC, patients with stricturing colonic lesions as well as incomplete colonoscopy, or in patients at risk of delayed access to timely OC. With an ever‐growing demand for endoscopic services, increased utilisation of CTC could reduce waiting times for colonoscopy, thereby broadening access to timely and effective CRC screening. Further research is required to improve further the detection of flat lesions, including sessile serrated polyps. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to evaluate if the application of Artificial Intelligence (AI) Colonoscopy CLN (ENDO‐AID) could increase the polyp detection rate (PDR). Methods and Materials: A single center retrospective study was performed in Tin Shui Wai Hospital. PDR in CLN from 11/2020 to 03/2021 after the application of ENDO‐AID (AI group) was compared to the cases from 12/2019 to 11/2020 before the application of the practice (non‐AI group). Procedures were performed by a single endoscopist with experience in performing > 3,000 CLN. Variables, such as patients' demographic data, indications, incidence of PDR, Boston Bowel Preparation Scale BBPS, withdrawal time, post CLN complication rate between the 2 groups, were compared. Categorical and continuous variables were analyzed by using the Chi‐Square test (Fisher exact test if appropriate) and Mann‐Whitney test respectively. Results were considered to be significant if p‐value < 0.05. Results: Total 234 patients were recruited. 115 patients (49.1%) were in the non‐AI group while 119 patients (50.9%) were in the AI group. The mean age of the non‐AI was higher than the AI group (65.3 vs 59.2, p< 0.001*), otherwise, there was no significant difference in sex (p = 0.05), percentage of smokers (20.8% vs 27.7%, p = 0.22), past medical history of IBD (0 vs 0, p = 1.0), family history of colorectal cancer (9 vs 9, p = 0.94), indications for CLN (e.g. follow up CLN for polyp/ cancer, per‐rectal bleeding, altered bowel habit etc. p > 0.05), BBPS (7.88 vs 8.04, p = 0.217), withdrawal time (7.65 min vs 7.48 min, p = 0.935), completion rate (95.6% vs 98.3%, p = 0.27) and complication rate (0% in both groups,p=1.0) between groups. In the contrary, PDR was significantly higher in the AI group than the non‐AI group (64.7% vs 46.0%, p = 0.003*). Besides, adenoma detection rate was also found significantly higher in the AI group than the non‐AI group (52.9% vs 37.4%, p = 0.017*). Conclusions: AI CLN can improve the PDR. [ABSTRACT FROM AUTHOR]

Purpose: Early detection and size quantification of renal calculi are important for optimizing treatment and preventing severe kidney stone disease. Prior work has shown that volumetric measurements of kidney stones are more informative and reproducible than linear measurements. Deep learning‐based systems that use abdominal noncontrast computed tomography (CT) scans may assist in detection and reduce workload by removing the need for manual stone volume measurement. Prior to this work, no such system had been developed for use on noisy low‐dose CT or tested on a large‐scale external dataset. Methods: We used a dataset of 91 CT colonography (CTC) scans with manually marked kidney stones combined with 89 CTC scans without kidney stones. To compare with a prior work half the data was used for training and half for testing. A set of CTC scans from 6185 patients from a separate institution with patient‐level labels were used as an external validation set. A 3D U‐Net model was employed to segment the kidneys, followed by gradient‐based anisotropic denoising, thresholding, and region growing. A 13 layer convolutional neural network classifier was then applied to distinguish kidney stones from false positive regions. Results: The system achieved a sensitivity of 0.86 at 0.5 false positives per scan on a challenging test set of low‐dose CT with many small stones, an improvement over an earlier work that obtained a sensitivity of 0.52. The stone volume measurements correlated well with manual measurements (r2=0.95$r^2 = 0.95$). For patient‐level classification, the system achieved an area under the receiver‐operating characteristic of 0.95 on an external validation set (sensitivity = 0.88, specificity = 0.91 at the Youden point). A common cause of false positives were small atherosclerotic plaques in the renal sinus that simulated kidney stones. Conclusions: Our deep‐learning‐based system showed improvements over a previously developed system that did not use deep learning, with even higher performance on an external validation set. [ABSTRACT FROM AUTHOR]

Summary: Background: Individuals with Lynch syndrome are at high risk for colorectal cancer (CRC). Regular colonoscopies have proven to decrease CRC incidence and mortality. However, colonoscopy is burdensome and interval CRCs still occur. Hence, an accurate, less‐invasive screening method that guides the timing of colonoscopy would be of important value. Aim: To outline the performance of non‐endoscopic screening modalities for Lynch‐associated CRC and adenomas. Methods: Systematic literature search in MEDLINE and EMBASE to identify studies investigating imaging techniques and biomarkers for detection of CRC and adenomas in Lynch syndrome. The QUADAS‐2 tool was used for the quality assessment of included studies. Results: Seven of 1332 screened articles fulfilled the inclusion criteria. Two studies evaluated either CT colonography or MR colonography; both techniques were unable to detect CRC and (advanced) adenomas <10 mm. The other five studies evaluated plasma methylated‐SEPTIN9, faecal immunochemical test (FIT), faecal tumour DNA markers (BAT‐26, hMLH1, p53, D9S171, APC, D9S162, IFNA and DCC) and faecal microbiome as screening modalities. Sensitivity for CRC varied from 33% (BAT‐26) to 70% (methylated‐SEPTIN9) to 91% (hMLH1). High specificity (94–100%) for CRC and/or adenomas was observed for methylated‐SEPTIN9, FIT and BAT‐26. Desulfovibrio was enriched in the stool of patients having adenomas. However, all these studies were characterised by small populations, high/unclear risk of bias and/or low prevalence of adenomas. Conclusions: Imaging techniques are unsuitable for colon surveillance in Lynch syndrome, whereas biomarkers are understudied. Having outlined biomarker research in Lynch‐associated and sporadic CRC/adenomas, we believe that these non‐invasive markers may hold potential (whether or not combined) for this population. As they could be of great value, (pre‐)clinical studies in this field should be prioritised. [ABSTRACT FROM AUTHOR]

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 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. 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). 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. [ABSTRACT FROM AUTHOR]

Colonoscopy is the gold standard to detect colon polyps prematurely. Early detection, characterization and resection of polyps decrease colon cancer incidence. Colon polyp missing rate remains high despite novel methods development. Narrowed-band imaging (NBI) is one of the image enhance techniques used to boost polyp detection and characterization, which uses special filters to enhance the contrast of the mucosa surface and vascular pattern of the polyp. However, the single-button-activated system is not convenient for a full-time colonoscopy operation. We selected three methods to simulate the NBI system: Color Transfer with Mean Shift (CTMS), Multi-scale Retinex with Color Restoration (MSRCR), and Gamma and Sigmoid Conversions (GSC). The results show that the classification accuracy using the original images is the lowest. All color transfer methods outperform the original images approach. Our results verified that the color transfer has a positive impact on the polyp identification and classification task. Combined analysis results of the mAP and the accuracy show an excellent performance of the MSRCR method. [ABSTRACT FROM AUTHOR]

• CTC-A consists of abdomino-pelvic CT with IV contrast injection that requires prior colonic preparation, colonic distension by CO 2 , and double tagging of residual stool with oral contrast agents. • CTC-A is a reproducible and well-tolerated examination with a very low risk of perforation (0.001%). • Compared to standard CT with IV contrast, CTC-A assesses the morphology of the entire colon and makes it possible to establish the precise location of the tumor, even in the case of dolichocolon, and to search for synchronous lesions, particularly when the colonoscope cannot traverse the tumor-bearing segment. It has a sensitivity and specificity of more than 90%. • CTC-A makes it possible to define the parietal extension of the tumor using sections perpendicular to the axis of the distended intestinal lumen and to discuss the indications for neo-adjuvant chemotherapy in the event of a locally advanced tumor. • Compared to standard thoraco-abdomino-pelvic (TAP) CT with IV contrast, CTC-A with image fusion also allows simultaneous vascular mapping of the colon at the tumor site and can help the surgeon to plan the colectomy (extent of the colectomy, variations in vascular anatomy, lymph node dissection). The pre-operative work-up for non-metastatic colon cancer includes colonoscopy and thoraco-abdomino-pelvic computed tomography (CT) with intravenous (IV) contrast. Colonoscopic determination of the anatomical location of the tumor may be erroneous, particularly with a long redundant colon (dolichocolon), and the search for synchronous colon neoplasms is limited when the endoscope cannot traverse the tumor-bearing segment. While computed tomography colonography angiography (CTC-A) makes it possible to assess distant tumor metastasis, it remains limited for the assessment of loco-regional extension. CTC-A requires specific colonic preparation, controlled colonic insufflation with CO 2 , and an injection of IV contrast. CTC-A provides a 3-D view of the overall morphology of the colon and precisely localizes the site of the colonic tumor. Merging the images of the colon with those of mesenteric and colonic vessels provides a representation of anatomical vascular variations. This information could help the surgeon to better plan the colectomy. The use of two-dimensional images of CTC-A with sections perpendicular to the major axis of the tumor-bearing colonic segment can provide precise information on the degree of parietal extension and be useful in evaluating the value of neo-adjuvant chemotherapy. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths globally. Nonetheless, with early detection of CRC or its precancerous lesions, mortality, and CRC incidence can be reduced. Although colonoscopy is currently the gold standard for CRC screening and diagnosis, its invasive nature, and troublesome bowel preparation deter patient participation. Therefore, there is a need to expand the use of noninvasive or minimally invasive methods to increase patient compliance. This review summarizes advances in different methods for CRC screening, including stool bacterial and metagenomic markers, fecal proteins, genetic and epigenetic markers in blood and stools, and imaging modalities. The cost-effectiveness of these methods is also discussed. FIT is more cost-effective compared to virtual colonoscopy, mSEPT9 test, and Multitarget Stool DNA test, while the cost-effectiveness of other noninvasive methods requires further evaluation. Recent evidence has well demonstrated the usefulness of gut microbiome and certain fecal bacterial markers in the noninvasive diagnosis of CRC and its precancerous lesions. Many of the fecal biomarkers, from host cells or the gut environment, show better diagnostic sensitivity than FIT. New screening tests based on these fecal biomarkers can be expected to replace FIT with higher cost-effectiveness in the near future. [ABSTRACT FROM AUTHOR]

Purpose: CT colonography enables three-dimensional measurement of colon length. However, previous studies using CT colonography have not examined the association with gender, age, physique, a history of laparotomy and bowel habits, all possible contributory factors to colon length. The aim of this study is to investigate factors associated with colon length. Materials and methods: We conducted a post hoc analysis based on data obtained from a previous multi-center trial including 321 patients with positive fecal immunochemical tests who underwent CT colonography. Colon length was measured using a computer-generated center line and was divided at the iliac crest level into the distal and proximal colons. Bowel habits were classified into three groups: A—daily; B—once every 2 or 3 days; and C—less than once in 3 days. Statistical comparison was made using one-way ANOVA with Bonferroni's correction. Results: A total of 295 patients were analyzed. The entire colon length (cm, mean ± standard deviation) of individual patients was 150.3 ± 18.5 cm and ranged from 109.7 to 195.9 cm. The female colon was significantly longer than the male colon (154.3 ± 18.1 cm vs. 147.1 ± 18.3 cm; p = 0.022). Colon length showed trends associated with age (p = 0.18) and a history of laparotomy (p = 0.14). According to bowel habits, the entire colon measured 147.4 ± 17.9 in group A, 154.7 ± 18.5 in group B and 158.6 ± 18.3 in group C, and significant differences were observed for "A vs. C" (p = 0.002) and "A vs. B" (p = 0.014). In subgroup analysis by colon segment, the proximal colon trended similarly to the entire colon while there were no trends for the distal colon. Conclusions: This study has clearly demonstrated that bowel habits and gender both correlate with the length of the entire colon measured by CT colonography, and in particular, the proximal colon. Using CT colonography, we measured the colon length in 295 patients. The entire colon length was 150.3 ± 18.5 cm on average. Females and constipated (less frequent defecation) patients have a significantly longer colon, and in particular, the proximal colon. Colon length showed trends associated with age and a history of laparotomy. [ABSTRACT FROM AUTHOR]

Introduction. Microwave imaging can obtain 360° anatomical and functional images of the colon representing the existing contrast in dielectric properties between different tissues. Microwaves are safe (nonionizing) and have the potential of reducing the visualization problems of conventional colonoscopy. This study assessed the efficacy of a microwave-based colonoscopy device to detect neoplastic lesions in an ex vivo human colon model. Methods. Fresh surgically excised colorectal specimens containing cancer or polyps were fixed to a 3D positioning system, and the accessory device was introduced horizontally inside the ex vivo colon lumen and moved along it simulating a real colonoscopy exploration. Measurements of the colon were taken every 4 mm with the microwave-based colonoscopy device and processed with a microwave imaging algorithm. Results. 14 ex vivo human colorectal specimens with carcinomas (n = 11) or adenomas with high grade dysplasia (n = 3) were examined with a microwave-based device. Using a detection threshold of 2.79 for the dielectric property contrast, all lesions were detected without false positives or false negatives. Conclusions. This study demonstrates the use of a microwave-based device to be used as an accessory of a standard colonoscope to detect neoplastic lesions in surgically excised colorectal specimens. [ABSTRACT FROM AUTHOR]

Introduction: Metastatic non-small cell lung cancer (NSCLC) is nowadays treated with a multimodal therapeutic approach including immunotherapy, targeted therapy and radiotherapy. Radiation therapy, in addition to immune checkpoint inhibitors, gives rise to a particular radiobiological effect known as "bystander effect" consisting of the radiation-induced damage in nearby unirradiated cells. Case report: We report a case of a 79-year-old female patient with stage IV NSCLC treated with concomitant immuno-radiotherapy who showed a bystander effect on bone. Management and outcome: Primary tumour biopsy revealed an adenocarcinoma with a PDL1 expression >50%, while staging exams showed a right pulmonary lesion with a partial involvement of the contiguous rib and a single brain metastasis. The patient refused chemotherapy, so that Pembrolizumab 2 mg/Kg was administered every 3 weeks. After two administrations, the single brain metastasis was treated using stereotactic radiosurgery while the site of primitive lung cancer received an 8 Gy-single fraction 3 D-conformal radiotherapy. Three months after irradiation a chest CT showed a radiological remission of about 10% of the GTV and a partial eburnation of the vertebra located nearby the target volume. The CT images of a PET/CT at six months showed a complete vertebral eburnation. At the last follow-up, the patient was free of disease (brain MRI, spinal MRI and PET/CT). Discussion: The present case alerts for unusual side effects provoked by bystander phenomenon in patients treated with a combination of immunotherapy and irradiation. Immune activation exacerbates the bystander effect causing normal tissues toxicities beyond what immunotherapies are causing by themselves. [ABSTRACT FROM AUTHOR]

Colorectal malignant polyps (MP) are polyps with invasive cancer into the submucosa harboring a variable risk of lymph node involvement, which can be estimated through evaluation of morphological, endoscopic, and histologic features. The recent advances in imaging endoscopic techniques have led to the possibility of performing an optical diagnosis of T1 colorectal cancer, allowing the selection of the best therapeutic modality to optimize outcomes for the patient. When MP are diagnosed after endoscopic removal, their management can be challenging. Differentiating low- and high-risk histologic features that influence the possibility of residual tumor, the risk of recurrence and the risk of lymph node metastasis, is crucial to further optimize treatment and surveillance plans. While the presence of high-risk features indicates a need for surgery in the majority of cases, location, comorbidities and the patient’s preference should be taken in account when making the final decision. This is a particularly important issue in the management of low rectal MP presenting with high-risk features, where chemoradiotherapy followed by a watch- and-wait strategy has demonstrated promising results. In this review we discuss the important prognostic features of MP and the most modern approaches regarding their management. [ABSTRACT FROM AUTHOR]

Purpose: Dual-layer spectral computed tomography (DLSCT) is a novel CT platform of dual-energy CT. Virtual non-contrast (VNC) imaging theoretically resembles true non-contrast (TNC) imaging by subtracting iodine attenuation from post-contrast data. We aimed to compare qualitative and quantitative datasets between TNC and VNC in patients with upper aerodigestive tract cancer (UATC) and to evaluate the potential radiation dose reduction obtained by omitting the TNC phase. Material and methods: The study included 61 patients with UATC who underwent DLSCT. The CT protocol included TNC and post-contrast phases. The VNC images were reconstructed from the post-contrast phase. The differences of mean CT attenuation values, imaging noise, and image quality for TNC and VNC images were compared. The effective radiation doses of a biphasic TNC and post-contrast CT protocol were compared with a single-phase protocol (post-contrast CT with VNC reconstruction). Results: There were a total of 732 ROIs from TNC and VNC. There was no statistical difference in the mean CT attenuation values between TNC and VNC images for all tissue types (p = 0.09-0.44), except for the buccal fat pad. Overall, 85.3% of cases revealed a difference of less than 10 HU. There was no significant difference in mean imaging noise (p = 0.5455) and image quality (p = 0.3214) between 2 acquisitions. All VNC images had acceptable quality for diagnostic purposes. The potential dose reduction by omitting the TNC was 49.5 ± 3.5%. Conclusion: VNC could replace TNC images in patients with UATC, with good image quality and the advantage of radiation dose reduction. [ABSTRACT FROM AUTHOR]

Background: The majority of percutaneous nephrolithotomies (PCNLs) are performed prone, whereas most preoperative CT scans are done supine. The purpose of this pilot study is to determine if there is utility of prone CT scans in preoperative planning for prone PCNL by identifying patient populations at risk for organ injury and tract length-related complications. Materials and Methods: To represent typical preoperative planning using CT, two-dimensional (2D)-axial-prone/supine percutaneous tract measurements were performed by minimizing the distance from the target calix to the posterior-lateral skin in a single axial plane. The minimum distance and organ interception rates for the 2D-axial planning scans were recorded. Results: A total of 60 CT colonography and 13 CT urography patients were included in analysis. There were 42 women and 31 men with unspecified pathology reports ranging in age from 27 to 86 years and in body mass index (BMI) from 17.1 to 49. Multiple logistic regression identified female gender and low BMI as predictors of organ interception on the left. On multiple linear regression comparing the difference in axial prone/supine lengths; BMI, gender, and age were not significant independent predictors of changes in tract length in any pole when prone vs supine. However, shorter supine tracts tended to lengthen when prone, and longer supine tracts tended to shorten. Conclusions: This pilot study has demonstrated that patients with long and short estimates of tract length in the supine position may have shorter and longer tracts, respectively, with repositioning to prone. Thus, prone CT may have benefit when anticipating exceptionally long (>15 cm) tract lengths. Prone scans also revealed more potential organ interceptions, particularly for low BMI and women in the left upper pole. In patients for whom prone CT demonstrates an organ interception, the urologist should consider an alternate target calix or ultrasound-guided percutaneous access to identify the most appropriate needle trajectory. [ABSTRACT FROM AUTHOR]

The role of radiology imaging in incomplete colonoscopy studies is discussed in terms of justification of barium enema and computed tomography colonography in accordance with current guidelines and practice. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the accuracy of computed tomography colonography (CTC) in differentiating chronic diverticular disease from colorectal cancer (CRC), using morphological and textural parameters. Materials and methods: We included 95 consecutive patients with histologically proven chronic diverticular disease (n = 53) or CRC (n = 42) who underwent CTC. One radiologist, unaware of histological findings, evaluated CTC studies for the presence of potential discriminators including: maximum thickness, involved segment length, shouldering phenomenon, growth pattern, diverticula, fascia thickening, fat tissue edema, loco-regional lymph nodes, mucosal pattern. Another radiologist performed volumetric texture analysis on the involved segment. Results: Several qualitative imaging parameters resulted to significantly correlated with colorectal cancer, including absence of diverticula in the affected segment, straightened growth pattern and shouldering phenomenon. A maximum wall thickness/involved segment length ratio < 0.1 had 98% specificity and 47% sensitivity in identifying diverticular disease. Regarding first-order texture analysis parameters, kurtosis resulted to be significantly different between the two groups. Conclusions: Absence of diverticula, straightened growth pattern and shouldering phenomenon are significantly associated with CRC (71–91% sensitivity; 82–91%). [ABSTRACT FROM AUTHOR]

Abstract CT colonography (CTC) is the radiological examination of choice for the diagnosis of colorectal neoplasia. Faecal tagging is considered a mandatory part of bowel preparation. However, the colonic mucosa, obscured by tagged residue, is not accessible to endoluminal 3D views and requires time-consuming 2D evaluation. Electronic cleansing (EC) software algorithms can overcome this limitation by digitally subtracting tagged residue from the colonic lumen. Ideally, this enables a seamless 3D endoluminal evaluation. Despite this benefit, EC is a potential source of a wide range of artefacts. Accurate EC requires proper CTC examination technique and faecal tagging. The digital subtraction process has been shown to affect the relevant morphological features of both colonic anatomy and colonic lesions, if submerged under faecal residue. This article summarises the potential effects of EC on CTC imaging, the consequences for reporting and patient management, and strategies to avoid pitfalls. Furthermore, potentially negative effects on clinical reporting and patient management are shown, and problem-solving techniques, as well as recommendations for the appropriate use of EC techniques, are presented. Radiologists using EC should be familiar with EC-related effects on polyp size and also with correct measurement techniques.

Objective: to compare the quality of residual colonic content tagging with 25 and 50 g of BAR-VIPS, the basе of which is barium sulfate (BaSO4), in preparing patients for virtual colonoscopy (VСS) and to evaluate the diagnostic efficiency of the method in both cases.Material and methods. The paper presents the results of VCS in 100 patients divided into two groups containing equal numbers (n = 50) according to the contrast medium dose (25 and 50 g). In each group, the quality of fecal tagging (FT) was compared by its presence and degree and by the presence and completeness of high-density artifacts for residual liquid and solid fragments separately. The reliability of the results of VCS versus fibrocolonoscopy was assessed in detecting additional colon tumors of three sizes (

The article discusses the importance of colorectal cancer (CRC) screening and the need for continued efforts to improve screening rates and reduce disparities. It highlights recent changes in CRC screening guidelines, including the recommendation to start screening at age 45 instead of 50. The article also mentions the importance of high-quality colonoscopy exams and the potential use of computer-aided detection (CADe) to improve detection rates. Additionally, it discusses the development of non-invasive CRC screening options and recent advances in CRC treatment. The article concludes by emphasizing the ongoing challenges in improving screening and treatment for CRC. [Extracted from the article]

This article discusses the surgical management of gut malrotation in an adult patient. Gut malrotation refers to congenital abnormalities in which the midgut fails to rotate properly during fetal development. The prevalence of gut malrotation in adults is still unknown, but it is often unrecognized due to nonspecific symptoms. The gold standard for diagnosis is a contrast-enhanced CT scan. The article introduces Kareem's procedure as an alternative surgical treatment for gut malrotation, which involves rotating the duodenum and placing the caecum and right colon in their proper positions. The article includes a video vignette of a patient who underwent Kareem's procedure successfully. The study was conducted without any funding and there were no conflicts of interest. [Extracted from the article]

Our PubMed search identified only a single reported case of simultaneous intussusception and volvulus.[9] Our patient's X-ray findings revealed a markedly dilated colon, and we suspected colon volvulus; however we could not confirm the existence of caecal volvulus and intussusception until CT was performed. Although the patient had extracted her ileus tube herself, we speculate that the ileus tube was not involved in this intussusception, because the balloon had already deflated and the intussusception did not occur in a retrograde manner. A 41-year-old Japanese woman with a history of schizophrenia and brain contusion, lumbar fracture, and pulmonary contusion due to a suicide attempt was admitted to our hospital because of abdominal pain and vomiting. [Extracted from the article]

Follow-up of small and diminutive colonic polyps - How to balance the risks in the COVID-19 era Polypectomy for diminutive polyps in elderly patients is similarly difficult to justify given the low risk of the polyps progressing within the patients' lifetime. Clinicians may feel uncomfortable about leaving diminutive polyps in younger patients who are at least 5 years from the bowel screening age given the risk of progression in the longer term. [Extracted from the article]

Background: Colonic masses are clinically important because some of them are malignant and others have a tendency to become malignant such as polyps. CT pneumocolon may have a role in the evaluation and diagnosis of these masses. Objective: To determine the accuracy of computed tomography (CT) pmeumocolon in the detection of colonic masses compared with colonoscopy. Patients and Methods: A total of 60 patients with colorectal symptoms underwent evaluation for the presence of colorectal neoplasms by using both colonoscopy and CT pneumocolon and a comparison was made between them. Results: On colonoscopy, 10 out of 60 patients were having a negative colonoscopy. The results of colonoscopy of the other 50 patients were as follow; three out of fifty colonoscopies revealed invasive colorectal carcinomas in threse patients. The remaining 47 colonoscopies for 47 patients revealed benign polyps. The sizes of these polyps were as follows; (6 polyps were ?1 cm in diameter), (17 polyps were 6-9 mm), and (24 polyps were =5 mm). CT pneumocolon detected all 3 malignant masses seen and biopsied by colonoscopy, but only (28 single polyps) which according to their size (4 polyps were = 1cm), (11 polyps were 6-9 mm) and (13 polyps =5 mm), this gives CT pneumocolon a sensitivity of (63%), specificity of (70%) and accuracy (63%). Conclusion: CT pneumocolon has high sensitivity and specificity for a detection of largesized masses, but not for small ones. CT pneumocolon may be suitable for investigating patients with symptomatic colorectal masses noninvasively. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has highlighted the importance of aerosol spread of infection. We have conducted a study to detect bacterial contamination of room surfaces and room air during CT colonography and confirm the efficacy of room disinfection procedures carried out between examinations. Systematic sampling of the CT examination couch and horizontal surfaces 1 m and 3 m from the couch was performed before and after patient examinations. A 1 m3 sample of room air was obtained during patient examinations. Samples were processed using routine laboratory methods. A case–control study design was used (30 CT colonography and 30 routine body CT scans). Evidence of airborne dissemination of bacteria was detected in >30% of CT colonography examinations and <10% of control examinations (p = 0.01). No pathogenic bacteria were detected in surface samples taken before patient examinations. The room disinfection policy in use in our CT department is effective in eliminating pathogenic bacteria from surfaces in the patient environment. CT colonography causes contamination of room air with enteric bacteria in a significant proportion of cases. CT colonography may possibly be an aerosol-generating procedure. Larger-scale investigation is needed to fully evaluate this potential infection risk. [ABSTRACT FROM AUTHOR]

In the Dutch National colorectal cancer (CRC) screening program, patients with a positive faecal immunochemical test (FIT) are referred for a colonoscopy. In a small proportion, because of contraindications, a computed tomographic colonography (CTC) is performed to rule out advanced neoplasia. The aim of our study is to evaluate the intra- and extra-colonic yield of CTC and its clinical implications. In this retrospective cohort study, all FIT positive patients who underwent primary (instead of colonoscopy) or secondary CTC (after incomplete colonoscopy) between January 2014 and January 2018 were included. Relevant intra-colonic lesions on CTC were defined as lesions suspected for CRC or >10 mm. Relevant extra-colonic findings were defined as E3 and E4 using the E-RADS classification. Of the 268 included patients, 66 (24.6%) were suspected to have CRC or 10 mm + lesion on CTC and 56 of them (84.8%) underwent an additional endoscopy. Another 20 patients with <10 mm lesions on CTC underwent additional endoscopy. Overall, 76/268 patients (28.4%) underwent confirmatory endoscopy of which 50 (18.7%) had histologic confirmed advanced neoplasia; 4.9% had CRC and 13.8% advanced adenoma. New relevant extra-colonic findings were detected in 13.8%. In the Dutch National CRC screening program, a CTC was followed by an endoscopic procedure in more than a quarter of patients, resulting in a significant number of advanced neoplasia. Overall, one out of seven CTCs showed new relevant extra-colonic findings which may lead to further diagnostic/therapeutic work-up. Our results can be important for the informed consent procedure. [ABSTRACT FROM AUTHOR]

Purpose: Accurate preoperative T staging is important when determining the treatment strategy for advanced colorectal cancer. We have previously reported the usefulness of preoperative T staging based on the spatial relationship of tumors and "bordering vessels" by computed tomography colonography (CTC) with multiplanar reconstruction (MPR). The aims of this study were to evaluate the external validity of this method and to determine whether there is a difference in the accuracy of T staging between the mesenteric and antimesenteric sides. Methods: The study subjects were 110 patients with colorectal cancer who underwent preoperative CTC and surgical resection from June 2016 to March 2018. Preoperative T stage was determined by CTC based on the relationship between the tumor and the bordering vessels and compared with the pathological T stage. The influence of tumor location, namely, whether the tumor was on the antimesenteric or mesenteric side, on preoperative T staging was assessed in 78 patients with colorectal cancer. Results: Sensitivity, specificity, accuracy, positive, and negative predictive values were respectively, 65%, 91%, 83%, 76%, and 85% for T2 (n = 34); 76%, 82%, 81%, 50%, and 94% for T3 (n = 23); and 77%, 93%, 87%, 86%, and 88% for T4a disease (n = 39). Overall right answer rate was 83.3% (15/18) for the mesenteric side and 65% (39/60) for the antimesenteric side (n = 0.14). Conclusion: Diagnostic criteria based on the bordering vessels seen on CTC images with MPR are useful for T staging of colorectal cancer. However, the accuracy differs between the antimesenteric and mesenteric sides. [ABSTRACT FROM AUTHOR]

An elderly female with a history of long-standing diverticulosis presented for CT colonography. A narrowing of an area in her sigmoid colon was visualised. Also visualised was cement leakage from a percutaneous vertebroplasty (PVP) that she underwent fifteen years ago for pain relief of osteoporotic collapse of two thoracolumbar vertebrae. Images of her diverticular disease, and of cement leakage as an extracolonic finding, are presented. Literature for both findings is discussed. [ABSTRACT FROM AUTHOR]

Bilateral small bowel inguinal hernia and examples of other abdominal wall hernias as extracolonic findings at CT colonography are discussed. An overview of hernia types and complications are presented. [ABSTRACT FROM AUTHOR]

An appendiceal lesion at computed tomographic colonography (CTC) could be a range of conditions which presents a diagnostic dilemma. The importance of careful scrutiny of 3D fly-through as well as 3D and 2D images is essential to exclude other possible appendiceal pathologies. A partial inversion and a complete inversion of the appendix at CTC are described. [ABSTRACT FROM AUTHOR]

Serrated polyps (SPs) were once considered benign, clinically unimportant lesions. However, it is now recognized that through the serrated neoplasia pathway (SNP), SPs play a role in the development of 15%-30% of cases of colorectal cancers (CRC). Furthermore, a high proportion of postcolonoscopy CRCs are believed to arise from SNP. Serrated polyps are classified into hyperplastic polyps, sessile serrated lesions, sessile serrated lesions with dysplasia, traditionally serrated adenomas, and unclassified serrated adenoma, each with a distinct morphological and molecular profile. Despite improved understanding, SPs remain a clinical challenge owing to evolving terminology, frequent pathologic misclassification, endoscopic underdetection, and high rates of incomplete removal. Surgeon endoscopists and surgeons who perform colorectal procedures will undoubtedly come across patients with SPs, and this paper summarizes some of the clinical challenges they will encounter. We also discuss the diagnosis and management of patients with serrated polyposis syndrome (SPS). [ABSTRACT FROM AUTHOR]

Colorectal cancer is the second leading cause of cancer-related deaths in the United States, but timely, effective, and adherent screening can reduce the number of cases. Screening tests continue to evolve, creating opportunities and challenges. Medical societies offer varying guidelines about optimal screening tests and when to begin screening. This article reviews available and emerging colorectal cancer screening tests and discusses how to educate patients, advise them in selecting an appropriate test, and promote increased participation in colorectal cancer screening. [ABSTRACT FROM AUTHOR]

Background: Artificial intelligence (AI) assistance has been considered as a promising way to improve colonoscopic polyp detection, but there are limited prospective studies on real‐time use of AI systems. Methods: We conducted a prospective, multicenter, randomized controlled trial of patients undergoing colonoscopy at six centers. Eligible patients were randomly assigned to conventional colonoscopy (control group) or AI‐assisted colonoscopy (AI group). AI assistance was our newly developed AI system for real‐time colonoscopic polyp detection. Primary outcome is polyp detection rate (PDR). Secondary outcomes include polyps per positive patient (PPP), polyps per colonoscopy (PPC), and non‐first polyps per colonoscopy (PPC‐Plus). Results: A total of 2352 patients were included in the final analysis. Compared with the control, AI group did not show significant increment in PDR (38.8% vs. 36.2%, p = 0.183), but its PPC‐Plus was significantly higher (0.5 vs. 0.4, p < 0.05). In addition, AI group detected more diminutive polyps (76.0% vs. 68.8%, p < 0.01) and flat polyps (5.9% vs. 3.3%, p < 0.05). The effects varied somewhat between centers. In further logistic regression analysis, AI assistance independently contributed to the increment of PDR, and the impact was more pronounced for male endoscopists, shorter insertion time but longer withdrawal time, and elderly patients with larger waist circumference. Conclusion: The intervention of AI plays a limited role in overall polyp detection, but increases detection of easily missed polyps; ChiCTR.org.cn number, ChiCTR1800015607. [ABSTRACT FROM AUTHOR]

Background and Aim: In Japan, screening colonoscopy for colorectal cancer is expected to reduce colorectal cancer mortality, although its complication rate has not been sufficiently examined. The aim of this study is to analyze severe complications due to colonoscopy. Methods: As a study population, we retrospectively used commercially anonymized health insurance claims data covering 5.71 million patients from January 2005 to August 2018. We extracted patients who received colonoscopy with lesions resection or without treatment. Main outcomes were rates of hemorrhage, perforation, fatal events, and their risk factors. Results: Among 341 852 colonoscopy without treatment in 260 128 patients (mean age: 49.6 ± 11.7 years), the rates of hemorrhage, perforation, and fatal events were 0.0059% (95% confidence interval [CI] 0.0031–0.0085), 0.0032% (95% CI 0.0011–0.0052), and 0.00029% (95% CI 0–0.0012), respectively. Regarding hemorrhage, compared with the rate for patients <50 years old (0.0050%), the rates for those 50–59, 60–69, and ≥70 years old were 0.0095% (P = 0.17), 0.0031% (P = 0.17), and 0%, respectively. Regarding perforation, compared with patients <50 years old (0.0056%), the rates for those 50–59, 60–69, and ≥70 years old were 0%, 0.0015% (P = 0.99), and 0.0102% (P = 0.99), respectively. A multivariate analysis for risk factors showed no significant findings for hemorrhage and perforation without treatment. Among 123 087 colonoscopy with lesions resection in 102 058 patients (mean age: 53.7 ± 9.3 years), the rates of hemorrhage, perforation, and fatal events were 0.136% (95% CI 0.1157–0.1572), 0.033% (95% CI 0.0228–0.0437), and 0.00081% (95% CI 0–0.0035), respectively. Conclusions: The analysis using health insurance claims data demonstrated the safety of colonoscopy. [ABSTRACT FROM AUTHOR]

Purpose: To determine whether the quality of a low-volume reduced bowel preparation (LV-RBP) for CT Colonography (CTC) is noninferior to full-volume reduced bowel preparation (FV-RBP) regimen. Methods: In this randomized controlled trial, consecutive participants referred for CTC were randomly assigned to receive LV-RBP (52.5 g of PMF104 in 500 mL of water) or FV-RBP (105 g of PMF104 in 1000 mL of water). Images were independently reviewed by five blinded readers who rated the quality of bowel preparation from 0 (best score) to 3 (worst score). The primary outcome was the noninferiority of LV-RBP to FV-RBP in the proportion of colonic segments scored 0 for cleansing quality, with noninferiority margin of 10%. Volume of residual fluids, colonic distension, lesions and polyps detection rates and patient tolerability were secondary outcomes. Results: From March 2019 to January 2020, 110 participants (mean age 65 years ± 14 [standard deviation]; 74 women) were allocated to LV-RBP (n = 55) or FV-RBP (n = 55) arms. There were 92% segment scored 0 in colon cleansing quality in LV-RBP and 94% in FV-RBP for prone scans, and 94% vs 92% for supine scans. Risk difference was – 2.1 (95% CI −5.9 to 1.7) and 1.5 (95% CI −2.4 to 5.4) for prone and supine positions, respectively. Residual fluids and colonic distension were also noninferior in LV-RBP. LV-RBP was associated with a lower number of evacuations during preparation (7 ± 5 vs 10 ± 6, p = 0.002). Conclusion: The LV-RBP for CTC demonstrated noninferior quality of colon cleansing with improved gastrointestinal tolerability compared to FV-RBP regimen. [ABSTRACT FROM AUTHOR]

Background: Reliable size measurement of lymph node (LN) metastases is important for the evaluation of cancer treatment. However, image analyses without proper settings may result in inappropriate diagnoses and staging. Purpose: To investigate whether reconstruction slice thickness in computed tomography (CT) affects measurements of LN size and reproducibility. Material and Methods: We analyzed 48 patients with histological diagnoses of sigmoid colon and rectal cancer who underwent contrast-enhanced CT colonography as part of a surgical treatment preparation. A board-certified radiologist selected 106 LNs whose short-axis diameter was ≥5 mm on 1-mm-thick images; the short-axis diameters were measured on 1- and 5-mm-thick images by the radiologist and residents and compared using Wilcoxon matched-pairs signed rank test. Data variation and reproducibility were evaluated using the F test and Bland–Altman analysis. P <0.05 was considered significant. Results: Short-axis diameters measured on 5-mm-thick images were significantly lower than those measured on 1-mm-thick images (P <0.01), even in the LNs whose short-axis diameters were over twice the slice thickness (P <0.05). Of the 106 LNs, 57 showed short-axis diameter <5 mm on 5-mm-thick images; the maximum short-axis diameter was 6.7 mm on a 1-mm thick image. Data variation was significantly larger on 5-mm thick images than 1-mm-thick images in small LNs (P <0.05) and reproducibility on 5-mm-thick images was inferior to that on 1-mm-thick images. Conclusion: Thick reconstruction slices in CT can result in an underestimation of LN size and reduce data reproducibility. When measuring LN size, a thin reconstruction slice would be recommended based on targeted LN size. [ABSTRACT FROM AUTHOR]

Aim To determine which flexible spectral imaging color enhancement (FICE) channel best visualizes colon mucosa in ulcerative colitis (UC) and to compare FICE imaging with standard imaging. Methods The study enrolled patients with ulcerative colitis in remission who had inflammatory bowel disease for at least 8 years. All patients underwent screening colonoscopy. The entire colon, especially the suspicious areas in terms of dysplasia, were imaged with standard endoscopy and FICE. Random and target biopsies were obtained. Histopathological diagnosis was made and image patterns were evaluated. Seven endoscopists evaluated normal, colitis, and polyp images obtained with FICE. Results One hundred and twenty-three colon segments were evaluated and 1831 images were obtained from 18 patients. A total of 1652 images were FICE and 179 were standard images. Separate FICE images were obtained for normal colon mucosa, polypoid lesions, and colitis areas. Normal colon mucosa was best visualized using the second, sixth, and ninth FICE channel; polyps using the third, seventh, and ninth channel; and colitis using the second, third, and ninth channel. When all images were analyzed, the second and ninth channel were significantly better than the other channels. A total of 584 biopsies were obtained, including 492 (84.2%) random biopsies and 92 (15.7%) target biopsies. Random biopsies detected no dysplasia, but target biopsies detected low-grade dysplasia in three diminutive polyps. Conclusion FICE was not significantly better at dysplasia screening than the standard procedure, but it effectively detected diminutive polyps and evaluated surface patterns without using magnification. FICE might contribute to the assessment of inflammation severity in patients with UC in clinical remission. However, more extensive studies are necessary to confirm these findings. [ABSTRACT FROM AUTHOR]