Computed Tomography Colonoscopy Research Articles

Role Development and Extension for Radiographers in Computed Tomography: Literature Review Findings and their Application to Zimbabwe

Computed Tomography (CT) technology has evolved into a vital diagnostic tool in modern medical practice, leading to the development and extension of the CT radiographer's role. While some countries have made progress in developing and extending radiographers' roles in CT, resource-constrained settings like Zimbabwe have been slower to implement these changes. The purpose of this review is to inform role changes for radiographers in Zimbabwe and similar settings by reviewing the literature on role development and extension for radiographers in CT. The review explores the concepts of role development and extension, emphasizing the necessity for changes in radiographers' roles in CT due to factors such as radiologists shortages, cost containment, quality improvement needs, and technological advancements. It also addresses the opposition to role development and extension, emphasizing the fundamental impetus for these changes should be to provide high-quality and effective patient-centered care. The paper delves into specific areas of role development and extension for radiographers in CT, including intravenous (IV) cannulation and contrast media administration, performing CT colonoscopy examinations, reporting on CT brains, and the significance of research and clinical audit in CT. It underscores the potential benefits of these expanded roles, such as improved patient care, workflow efficiency, and the workload of radiologists, as well as advancements in education, service delivery, and technological innovations. The review underscores the need for further research to ensure evidence-based implementation of role development and extension for radiographers in CT. Embracing these changes and providing the necessary support and training can lead to improved patient care, address skill shortages, and advance the radiography profession in resource-constrained settings like Zimbabwe.

Clinical significance of abdominal computed tomography and colonoscopy in the evaluation of phlebosclerotic colitis.

Clinical manifestations of phlebosclerotic colitis (PC) exhibit significant variability, necessitating diverse treatment strategies depending on disease severity. However, there is limited research exploring the relationship between imaging findings and disease severity. Hence, this retrospective study aimed to analyze the correlation between computed tomography (CT) findings, colonoscopic features, and disease severity. This study compared the abdominal CT characteristics, colonoscopy findings, and treatment modalities of 45 PC patients. CT images were assessed for the severity of mesenteric venous calcification, maximum colonic wall thickness, number of involved colonic segments, and presence of pericolic inflammation. Colonoscopic images were assessed for dark purple discoloration mucosa, erosive and ulcerative lesions, mucosal edema, luminal narrowing, and the number of involved colonic segments. In addition, patients were categorized into three groups: the observation (n = 15), medical treatment (n = 19), and operation (n = 11) groups. In CT images, a significant difference in pericolic inflammation (p = 0.039) was observed among groups. Further, significant differences in dark purple discoloration mucosa (p = 0.033), erosive or ulcerative lesions (p < 0.001), mucosal edema (p < 0.001), luminal narrowing (p = 0.012), and the number of involved colonic segments (p = 0.001) were observed in colonoscopy. Moreover, we found positive correlations between CT and colonoscopy features. In conclusion, CT manifestations and colonoscopy findings exhibited correlation with disease severity in PC. When limited to one diagnostic tool, observations from that tool can infer potential manifestations of the alternative tool.

High Concordance of CT Colonography and Colonoscopy Allows for the Distinguishing and Diagnosing of Intestinal Diseases.

(1) Although new imaging methods for examining the GIT with high diagnostic capabilities were introduced, the improvement and implementation of safe, efficient, and cost-effective approaches continue, and GIT diseases are still challenging to diagnose; (2) Methods: We aim to show the possibilities of computed tomography (CT) colonography for early diagnosis of colon diseases using a multidetector 32-channel CT scanner after appropriate preparation; (3) Results: After a colonoscopy was performed earlier, 140 patients were examined with CT colonography. Complete colonoscopy was performed in 80 patients (57.1%) out of 140 who underwent CT colonography. Incomplete colonoscopy was observed in 52 patients (37.2%); in 5 patients (3.6%), it was contraindicated, and in 3 patients (2.1%), it was not performed because of patients' refusal. We determined that in cases of complete FCS in 95% of patients, CT colonography established the same clinical diagnosis as FCS. In cases of incomplete, refused, or contraindicated FCS in 32.7% (17 patients), FCS failed to diagnose correctly. The main reasons for incomplete colonoscopy were: intraluminal obturation of tumor nature-17 patients (33%), extraluminal obturation (compression) from a tumor formation-4 patients (8%), stenotic changes of non-tumor nature-11 patients (21%), congenital diseases with changes in the length of the lumen of the intestinal loops-7 patients (13%), and subjective factors (pain, poor preparation, contraindications) in 13 patients (25%); (4) Conclusions: Our results confirmed that CT colonography is a method of choice in cases of negative FCS results accompanied by clinical data for the neoplastic process and in cases of incomplete and contraindicated FCS. Also, the insufflation system we developed optimizes the method by improving the quality of the obtained images and ensuring good patient tolerance.

The Accuracy of Different Modalities Used for Preoperative Primary Tumour Localisation in Operated Colorectal Cancer Patients.

Aim Colonoscopy and computed tomography (CT) scans of the abdomen and pelvis areroutine pre-operative assessment tools in colorectal cancer (CRC) patients. There have been some discrepancies regarding the location of cancer when seen by colonoscopy versus CT scan. The purpose of this study was to compare the accuracy of a colonoscopy with a computed tomography (CT) scan of the abdomen and pelvis with contrast, which is done routinely before surgery to localise the exact site of the tumour within the large bowel, whilst comparing both to the operative, grossand histopathology findings of the exact location. Methods A retrospective study was carried out on 165 colorectal cancer patients operated on between January 1, 2010, and December 31, 2014, using electronic hospital records that were reviewed anonymously, comparing the location of cancer within the large bowels as was found on colonoscopy and CT scan of the abdomen and pelvis with contrast, comparing both to post-operative histopathology specimen or intra-operative assessment in cases where no resection of the primary tumour was performed. Results CT and colonoscopy were both accurate in diagnosing 70.5% of cases that had done both investigations pre-operatively. The best results were obtained when the cancer was located in the caecum as confirmed post-operatively; the combined accuracy rate was 100%. CT was accurate, whilst colonoscopy was not in eight (6.2%)cases (all are rectal or sigmoid cancers), andcolonoscopy was accurate and CT was not in 12 cases, 10 of them were rectal and two were ascending colonic. Colonoscopy was not performed in 36 (21%)cases for a variety of reasons, including large bowel obstruction or perforation on presentation. In 32 of these cases, CT scan managed to accurately predict the location of cancer (mostly rectal and caecal), and CT scan was inaccurate in 20.6% of cases (34 out of 165), whilst colonoscopy was inaccurate in 13.9% of cases (18 out of 129). Conclusion Colonoscopy is more accurate in localising colorectal cancers than CT scan of the abdomen and pelvis with contrast. CT scan diagnoses regional and distant spread of colorectal cancers such as nodal status, invasion of neighbouring organsand/or peritoneum and the presence of liver metastases, whilst colonoscopy is limited to intraluminal diagnosis but can be both a diagnostic and therapeutic tool, with higher accuracy, in general, in localising colorectal cancers. Both CT scan and colonoscopy were equal in appendicular, caecal, splenic flexureand descending colon cancerlocalisation accuracy.

Three-dimensional reconstruction of computed tomography colonography discloses anatomic features associated with colonoscopy failure.

Three-dimensional virtual reality (3D VR) permits precise reconstruction of computed tomography (CT) images, and these allow precise measurements of colonic anatomical parameters. Colonoscopy proves challenging in a subset of patients, and thus CT colonoscopy (CTC) is often required to visualize the entire colon. The aim of the study was to determine whether 3D reconstructions of the colon could help identify and quantify the key anatomical features leading to colonoscopy failure. Retrospective observational study. Using 3D VR technology, we reconstructed and compared the length of various colonic segments and number of bends and colonic width in 10 cases of CTC in technically failed prior colonoscopies to 10 cases of CTC performed for non-technically failure indications. We found significant elongation of the sigmoid colon (71 ± 23 cm versus 35 ± 9; p = 0.01) and of pancolonic length (216 ± 38 cm versus 158 ± 20 cm; p = 0.001) in cases of technically failed colonoscopy. There was also a significant increase in the number of colonic angles (17.7 ± 3.2 versus 12.7 ± 2.4; p = 0.008) in failed colonoscopy cases. Increased sigmoid and pancolonic length and more colonic bends are novel factors associated with technical failure of colonoscopy.

Deep Learning for Detection of Colonic Polyps from Computed Tomography Colonoscopy Images Combined with Colonoscopy

The objective of this study was to investigate the diagnosis of colonic polyps (CP) through the computed tomography (CT) images combined with colonoscopy based on Fourier central slice theorem algorithm. In this study, 86 patients with CP admitted to hospital were selected as research objects. CT imaging and colonoscopy were applied to diagnose the patients based on the algorithm of Fourier central slice theorem. The results showed that the diagnostic detection rates of CP and colon cancer (CC) were 88.2% and 94.2%, respectively. The occurrence site of CP was the sigmoid and ascending colon. 38 patients were positive for serosal invasion of CP while 42 patients were negative for serosal invasion of CP, and there were no statistical differences ( P &gt; 0.05 ). The lesion positions of remaining 6 cases were hard to find and could not be detected accurately. Besides, the diagnostic accuracy of preoperative and postoperative stages III and IV was all 100.00%. The combination of CT imaging and colonoscopy was employed to diagnose CP, which was found to be able to accurately locate the lesions, to effectively evaluate the tumor stage before and after surgery, and to have a good diagnostic efficacy in detecting tumor serosal layer.

Factors of incomplete colonoscopy for stenosing colorectal cancer: CT colonography features.

The purpose of this study was to examine the relation between computed tomography colonoscopy (CTC) features of colorectal cancer (CRC) and incomplete colonoscopy. The subjects of this retrospective study consisted of 108 patients with advanced CRC (57 men, 51 women; age range, 32-87years; median, 65years) who underwent CTC. We compared local CTC features between the groups of complete (n = 74) and incomplete colonoscopy (n = 34). We performed a receiver operating characteristic (ROC) analysis to assess a diagnostic performance of CTC features to predict incomplete colonoscopy. The cross-sectional area of tumor and stenosis of complete colonoscopy group were significantly smaller and larger than those of incomplete colonoscopy group (p = 0.001 and < 0.001). Circumferential tumor extent rate (CER) showed significantly higher in the incomplete colonoscopy group than complete colonoscopy group (p < 0.001). In the ROC analysis, the cross-sectional area of stenosis showed AUC of 0.916, which was the best to predict incomplete colonoscopy. CTC features including larger cross-sectional area of tumor, smaller cross-sectional area of stenosis and 100% CER were significantly associated with incomplete colonoscopy for the patients with CRC.

Other imaging techniques: Double-contrast barium enema, endoscopic ultrasonography, multidetector CT enema, and computed tomography colonoscopy.

Double-contrast barium enema (DCBE), transrectal endoscopic ultrasonography (REU), multidetector computerized tomography enema (MDCT-e), and computed tomography colonoscopy (CTC) have been successfully used for the diagnosis of bowel endometriosis. DCBE provides a complete overview of the entire colon and allows detecting cecal nodules. The accuracy of DCBE is operator dependent and, thus, it may have low specificity. It does not allow identifying the cause of the mass effect. DCBE requires the administration of barium and exposure to radiation. REU precisely estimates the distance between the rectosigmoid nodule and the anal verge. However, it allows investigating only the distal part of rectosigmoid, it misses anterior pelvic lesions, and it has poor sensitivity for the diagnosis of endometriomas. MDCT-e is accurate and reproducible in diagnosing intestinal endometriosis and in assessing its characteristics: the largest diameter of the nodule, the distance between the distal part of the nodule and the anal verge, and depth of infiltration of endometriosis in the intestinal wall. MDCT-e requires the administration of iodinated contrast medium (CM) and the exposure to radiations. CTC has good performance in the diagnosis of rectosigmoid endometriosis. It allows estimating the degree of intestinal stenosis CTC, and the distance between the intestinal endometriotic nodule and the anal verge. It requires exposure to radiations, and it may require the administration of an iodinated CM.

Performance of computed tomography colonoscopy (CTC) in comparison to colonoscopy in the two-week wait lower gastrointestinal (GI) pathway

Category: GI/GU

Resection of rectal cancer resembling submucosal tumor that was preoperatively diagnosed with endoscopic ultrasound-guided biopsy

BackgroundColorectal cancer (CRC) resembling submucosal tumor (SMT; CRC/SMT) is very rare. Because its biopsy is challenging, accurate preoperative diagnosis is also very rare.Case presentationA 55-year-old woman with a high serum carcinoembryonic antigen level underwent a computed tomography colonoscopy, which showed extrinsic rectum compression. A coronal magnetic resonance image showed a 4-cm low-intensity tumor between her rectum and sacrum. Endoscopic ultrasound (EUS) showed a 30-mm low-echoic lesion originating from the rectum. Pathological examination of specimen obtained with EUS-guided fine-needle aspiration biopsy (EUS-FNAB) revealed adenocarcinoma. Immunohistochemical staining showed the tumor to be positive for both CK20 and CDX2 and negative for CK7, indicating that it was a rectal cancer. We performed a laparoscopy-assisted low-anterior resection with dissection of the regional lymph nodes after eight chemotherapy cycles. Macroscopically, tumor was completely covered by normal rectal mucosa, but showed a 2-mm bulge on the mucosa. Histological examination revealed a moderately differentiated adenocarcinoma, mainly located at the subserosal layer and severely invaded to lymphatic and blood vessels. The mucosal layer was not exposed to the cancer components, and her postoperative course was uneventful.ConclusionEUS-FNAB was useful in preoperative accurate diagnosis of this very rare tumor. We also review the literature and discuss CRC/SMT.

Insurance Coverage for CT Colonography Screening: Impact on Overall Colorectal Cancer Screening Rates.

Purpose To compare overall colorectal cancer (CRC) screening rates for patients who were eligible and due for CRC screening and who were with and without insurance coverage for computed tomographic (CT) colonography for CRC screening. Materials and Methods The institutional review board approved this retrospective cohort study, with a waiver of consent. This study used longitudinal electronic health record data from 2005 through 2010 for patients managed by one of the largest multispecialty physician groups in the United States. It included 33 177 patients under age 65 who were eligible and due for CRC screening and managed by the participating health system. Stratified Cox regression models provided propensity-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the relationship between CT colonography coverage and CRC screening. Results After adjustment, patients who had insurance coverage for CT colonography and were due for CRC screening had a 48% greater likelihood of being screened for CRC by any method compared with those without coverage who were due for CRC screening (HR, 1.48; 95% CI: 1.41, 1.55). Similarly, patients with CT colonography coverage had a greater likelihood of being screened with CT colonography (HR, 8.35; 95% CI: 7.11, 9.82) and with colonoscopy (HR, 1.38; 95% CI: 1.31, 1.45) but not with fecal occult blood test (HR, 1.00; 95% CI: 0.91, 1.10) than those without such insurance coverage. Conclusion Insurance coverage of CT colonography for CRC screening was associated with a greater likelihood of a patient being screened and a greater likelihood of being screened with a test that helps both to detect cancer and prevent cancer from developing (CT colonography or colonoscopy). © RSNA, 2017.

Diagnostic Performance and Patient Acceptance of Reduced-Laxative CT Colonography for the Detection of Polypoid and Non-Polypoid Neoplasms: A Multicenter Prospective Trial.

Purpose To evaluate the diagnostic accuracy and patient acceptance of reduced-laxative computed tomographic (CT) colonography without computer-aided detection (CAD) for the detection of colorectal polypoid and non-polypoid neoplasms in a population with a positive recent fecal immunochemical test (FIT). Materials and Methods Institutional review board approval and written informed consent were obtained. This multicenter prospective trial enrolled patients who had positive FIT results. Reduced-laxative CT colonography and colonoscopy were performed on the same day. Patients received 380 mL polyethylene glycol solution, 20 mL iodinated oral contrast agent, and two doses of 20 mg mosapride the day before CT colonography. The main outcome measures were the accuracy of CT colonography for the detection of neoplasms 6 mm or larger in per-patient and per-lesion analyses and a survey of patient perceptions regarding the preparation and examination. The Clopper-Pearson method was used for assessing the 95% confidence intervals of per-patient and per-lesion accuracy. Survey scores were analyzed by using the Wilcoxon and χ2 tests. Results Three hundred four patients underwent both CT colonography and colonoscopy. Per-patient sensitivity, specificity, positive predictive value, and negative predictive value of CT colonography for detecting neoplasms 10 mm or larger were 0.91 (40 of 44), 0.99 (255 of 258), 0.93 (40 of 43), and 0.98 (255 of 259), respectively; these values for neoplasms 6 mm or larger were 0.90 (71 of 79), 0.93 (207 of 223), 0.82 (71 of 87), and 0.96 (207 of 215), respectively. Per-lesion sensitivities for detection of polypoid and non-polypoid neoplasms 10 mm or larger were 0.95 (40 of 42) and 0.67 (six of nine), respectively; those for neoplasms 6 mm or larger were 0.90 (104 of 115) and 0.38 (eight of 21), respectively (P < .05 for both). Patient acceptance of preparation and examination with CT colonography was significantly higher than that with colonoscopy, and 62% (176 of 282) of patients would choose CT colonography as the first examination if they have a positive FIT result in the future. Conclusion Reduced-laxative CT colonography without CAD is accurate in the detection of polypoid neoplasms 6 mm or larger but is less accurate in the detection of non-polypoid neoplasms. Reduced-laxative CT colonography has high patient acceptance and is an efficient triage examination for patients with a positive FIT. © RSNA, 2016 Online supplemental material is available for this article.

Novel Method for Screening Colorectal Neoplasm

Colorectal cancer (CRC) is one of the leading causes of cancer death worldwide with the majority of cases having no previous family history. The most effective way to reduce mortality is to detect precancerous adenoma in an early stage. Several screening methods are now available; however as each modality has its limitation there is no superb strategy so far to conquer cancer death with colorectal cancer (Winawer et al., 1997). Fecal occult blood testing (FOBT) is the most widely employed screening tools, but sensitivity varies from 30% to 90% and depends on whether the specimens are rehydrated or not. The value of colonoscopy in screening can be appreciated, but it is costly and invasive. Moreover its effectiveness also depends on the endoscopist's skill. Computed tomographic colonoscopy (CTC) may another modality and rapidly evolving, but there are no controlled trials of screening CTC (Johnson et al., 2008). The risk of cumulative radiation exposure is also unknown. A special adaptation of capsule endoscopy has been developed to obtain images of the colon using tiny video cameras embedded in the two ends of an ingested capsule; however several studies have found a relatively low sensitivity for polyp detection (Rokkas et al., 2010). Current serum markers are not sufficiently sensitive or specific to be used for screening. The advent of 16S rRNA-based analyses has allowed investigation of the human colonic microbiota at the level of phylotypes and bacterial species (Shen et al., 2010). The rationale of this method applying for the colorectal cancer screening is intriguing. In the colon, trillions of commensal bacteria, termed the microbiota, are in close proximity to a single layer of epithelial cells. Evidence from animal and human studies suggests that intestinal commensal bacteria are not innocent bystanders but rather active participants in health. They contribute to the regulation of cell proliferation, differentiation and gene expression in host epithelial cells (Sanapareddy et al., 2012). Goedert et al. reported a very interesting research to address a new way of screening colorectal neoplasm (Goedert et al., 2015). They have created a cancer screening project in Shanghai area with combined methods of fecal immunohistochemical test (FIT), colonofiber and microbiota analysis. After informed consent was provided by 95 consecutive FIT positive patients, 61 patients had successful fecal microbiota profiling and colonoscopy. They confirmed 24 completely normal patients, 20 colorectal adenoma (CRA), 2 colorectal carcinoma and 15 with other conditions. Through the meticulous statistical analysis, they found that most of the compositional difference between CRA and normals reflected relative abundance of Proteobacteria taxa (p = 0.04) and, to a lesser extent, rare candidate division TM7 taxa (p = 0.04). Median relative abundance of Proteobacteria taxa was 3-fold higher in CRA than in normals (p = 0.03). They developed and applied a rank-based distance metric to quantify and test for differences in composition (beta diversity). This method originated with the Wilcoxon rank-sum test, with which CRA associations were observed across most of 18 detected phyla. They suggest that this method is feasible and effective. Recently, many efforts have been made to unveil the contribution of intestinal microbiota to gut diseases, employing culture-independent techniques (Goedert et al., in press, McCoy et al., 2013). In contrast to gastric cancer, where just one bacteria (Helicobacter pylori) has been associated as to the disease, no single bacterial species has been identified as a risk factor for CRC. But current studies accumulate many interesting data from Bench to Bedside in terms of microbiota contribution to colorectal neoplasm (Dennis et al., 2013). In general, the cancer screening test needs several important points. It must be convenient to patients, and have good sensitivity and specificity with relative low cost. In terms of cost, such new technique as 16S rRNA-based analyses is still expensive. Therefore researchers have to take the balance between patient's welfare and national economy. Less expensive analyses such as fecal pH or organic acids including short chain fatty acid (SCFA) may become a candidate of screening for colorectal cancer (Ohigashi et al., 2013). Changes of these factors affect microbial community, and promote carcinogenesis either directly or indirectly. While the causes of colorectal cancer are not fully known, it is becoming increasingly clear that the gut microbiota provide an important contribution (Arthur et al., 2012). To identify the composition of bacterial communities in the colon is an important step in our understanding of their role in the large bowel cancer and development of effective prognostic, preventative or therapeutic strategies. In more diverse populations fecal microbiota analysis might be employed to improve for colorectal adenoma and ultimately reduce mortality from CRC.

Tu1556 Cost Effectiveness Analysis of Enteroscope Utilization Versus Colon Capsule or Computed Tomography Colonoscopy for Patients With Incomplete Colonoscopy

Tu1556 Cost Effectiveness Analysis of Enteroscope Utilization Versus Colon Capsule or Computed Tomography Colonoscopy for Patients With Incomplete Colonoscopy

Noncathartic CT Colonography to Screen for Colorectal Neoplasia in Subjects with a Family History of Colorectal Cancer

To prospectively assess the diagnostic performance of noncathartic computed tomographic (CT) colonography in the detection of clinically relevant colorectal lesions (≥6 mm polyps or masses) in a well-defined cohort of first-degree relatives of patients with colorectal cancer (CRC), using colonoscopy and histologic review as the standard of reference. Institutional review board approval was obtained, and all subjects provided written informed consent. Consecutive patients admitted with CRC (index cases) were prospectively evaluated, and those who agreed to contact their first-degree relatives who were at least 40 years old were included. Available first-degree relatives were invited to undergo noncathartic CT colonography (200 mL of diatrizoate meglumine and diatrizoate sodium). Colonoscopy was performed the following day, and findings from CT colonography were disclosed for each segment. Sensitivity, specificity, and positive and negative predictive values of CT colonography were assessed for detecting subjects with any lesion at least 6 mm, any lesion at least 10 mm, and advanced neoplasia at least 6 mm. Colonoscopy with segmental unblinding and histologic diagnosis were used as the standard of reference. Matching between findings from CT colonography and colonoscopy was allowed when lesions were located in the same or adjacent colon segments and when the size difference was 50% or less. Three hundred four first-degree relatives (median age, 47 years; age range, 40-79 years; 46.7% women) identified from 221 index cases were included. Overall, CT colonography helped identify 17 of 22 subjects with polyps measuring at least 6 mm (sensitivity, 0.77; 95% confidence interval [CI]: 0.59, 0.95) and helped correctly classify as negative 278 of 282 subjects without lesions measuring at least 6 mm (specificity, 0.99; 95% CI: 0.97, 1.00). CT colonography helped detect eight of nine subjects with polyps measuring at least 10 mm as well as eight of nine subjects with advanced neoplasia measuring at least 6 mm (sensitivity, 0.89 for both). Per-subject positive and negative predictive values for lesions measuring at least 6 mm were 0.81 (17 of 21 subjects; 95% CI: 0.65, 0.97) and 0.98 (282 of 287 subjects; 95% CI: 0.96, 0.99), respectively. Noncathartic CT colonography is an effective screening method in first-degree relatives of patients with CRC.

Lipomas in large bowel

CASE REPORT A 61­year­old male with a history of peptic ulcer disease and prostatectomy presented to the emergency department with massive lower gastrointestinal bleeding, melena and diffuse abdominal pain. The patient had a history of lower gastrointestinal bleeding associated with diffuse abdominal pain and changes in bowel movements, alternating between diarrhea and constipation. Colonoscopy (Figure 1, 2) and computed tomography (CT) scan (Figure 3) revealed numerous submucosal lipomatous lesions in several bowel segments with the largest measuring approximately 7.2 cm, found in the transverse colon. Pre­ and post­ contrast CT scan showed lesions with radiodensity consistent with fatty tissue in the lumen of the transverse colon (arrow) (Figure 3). CT scan and colonoscopy showed no bowel obstruction or intussusception. We were unable to perform biopsy of the lesion due to risk of perforation. The patient was kept on watchful waiting and showed improvement in signs and symptoms during hospitalization.

Pneumatosis cystoides intestinalis: Modern diagnostic modalities

We read with interest the article by Masuda et al. [1] on the use of computed tomographic (CT) colonoscopy for the diagnosis of pneumatosis cystoides intestinalis. We would like to share our experience of a similar case. A 73-year-old woman with history of hypertension and ischemic stroke was referred for evaluation of chronic constipation and abdominal distention. Taking into account the patient's desire for a non-invasive exploration, a CT colonoscopy was initially performed; CT disclosed multiple air-containing cysts within the wall of the sigmoid colon, suggesting the diagnosis of idiopathic pneumatosis cystoides intestinalis (Fig.

Intravenous contrast enhanced computed tomography colonoscopy in children with suspected colonic polyps

ObjectiveThe purpose of this study was to evaluate the diagnostic performance of intravenous contrast enhanced computed tomographic colonoscopy (IVCTC) in the diagnosis of clinically suspected colorectal polyps in children, using conventional colonoscopy (CC) as the gold standard. MethodsThis was a prospective study conducted between July 2008 and June 2010. 30 pediatric patients with history of rectal bleeding and clinically suspected to have colorectal polyps were enrolled. All of the patients underwent IVCTC followed by CC. 30 IVCTC and 31 CC were performed in 30 patients. The findings of IVCTC were compared with those of CC. Statistical analysis was performed to obtain diagnostic performance values of IVCTC on per polyp (sensitivity and positive predictive value) and per patient (sensitivity, specificity, positive predictive value and negative predictive value) basis. ResultsBy IVCTC, 63 polyps were detected in 28 patients of which 53 polyps were eligible for inclusion in the statistical analysis. 60 polyps were detected by CC in 28 patients of which 50 polyps were eligible for inclusion in the statistical analysis. The per polyp sensitivity and positive predictive values were 94% and 88.6% respectively. The per patient sensitivity, specificity, positive predictive value, and negative predictive values were 96.4, 50, 96.4, and 50% respectively. Twenty polyps, in 10 patients, were visualized only after intravenous contrast administration of which 5 polyps, in 5 patients, were likely to have been missed in the absence of the intravenous contrast injection as these polyps were submerged in fluid. Four patients would have had a false negative CTC examination if the intravenous contrast had not been injected; while in another patient, the number of polyps would have been underestimated. ConclusionCTC is capable of serving as a safe and efficient non-invasive tool for evaluating children with clinically suspected colorectal polyps. Administration of intravenous contrast improves the sensitivity of polyp detection on CTC.

Virtual colonoscopy: Utility, impact and overview

Computed tomography (CT) colonoscopy is a well-established technique for evaluation of colorectal cancer. Significant advances have been made in the technique of CT colonoscopy since its inception. Excellent results can be achieved in detecting both colorectal cancer and significant sized polyps as long as a meticulous technique is adopted while performing CT colonoscopy. Furthermore, it is important to realize that there is a learning curve involved in interpreting these studies and adequate experience is essential to achieve high sensitivity and specificity with this technique. Indications, contraindications, technique and interpretation, including potential pitfalls in CT colonoscopy imaging, are reviewed in this article. Recent advances and the current role of CT colonoscopy in colorectal cancer screening are also discussed.

Colorectal cancer: Current imaging methods and future perspectives for the diagnosis, staging and therapeutic response evaluation

In the last 10 years the mortality rate of colorectal cancer (CRC) has decreased by more than 20% due to the rising developments in diagnostic techniques and optimization of surgical, neoadjuvant and palliative therapies. Diagnostic methods currently used in the evaluation of CRC are heterogeneous and can vary within the countries and the institutions. This article aims to discuss in depth currently applied imaging modalities such as virtual computed tomography colonoscopy, endorectal ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnosis of CRC. Special focus is put on the potential of recent diagnostic developments as diffusion weighted imaging MRI, MRI biomarkers (dynamic enhanced MRI), positron emission tomography with 2-(fluorine-18)-fluoro-2-deoxy-D-glucose (FDG-PET) combined with computed tomography (PET/CT) and new hepatobiliary MRI contrast agents. The precise role, advantage and disadvantages of these modalities are evaluated controversially in local staging, metastatic spread and treatment monitoring of CRC. Finally, the authors will touch upon the future perspectives in functional imaging evaluating the role of integrated FDG-PET/CT with perfusion CT, MRI spectroscopy of primary CRC and hepatic transit time analysis using contrast enhanced ultrasound and MRI in the detection of liver metastases. Validation of these newer imaging techniques may lead to significant improvements in the management of patients with colorectal cancer.