Magnetic resonance enterography in Crohn's disease: How we do it and common imaging findings.

Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract, with unpredictable clinical course by phases of relapses alternating with other of quiescence. The etiology is multifactorial and is still not completely known; globally the westernization of lifestyle is causing an increasing incidence of CD, with peak age of 20-30 years. The diagnostic workup begins with the evaluation of the clinical history, physical examination and laboratory tests. However, the clinical assessment is subjected interobserver variability and, occasionally, the symptoms of acute and chronic inflammation may be indistinguishable. In this regards, the role of magnetic resonance (MR) enterography is crucial to determine the extension, the disease activity and the presence of any complications without ionizing radiations, making this method very suitable for young population affected by CD. The purpose of this review article is to illustrate the MR enterography technique and the most relevant imaging findings of CD, allowing the detection of small bowel involvement and the assessment of disease activity.

Computed tomography colonography for the practicing radiologist: A review of current recommendations on methodology and clinical indications.

Colorectal cancer (CRC) represents one of the most relevant causes of morbidity and mortality in Western societies. CRC screening is actually based on faecal occult blood testing, and optical colonoscopy still remains the gold standard screening test for cancer detection. However, computed tomography colonography (CT colonography) constitutes a reliable, minimally-invasive method to rapidly and effectively evaluate the entire colon for clinically relevant lesions. Furthermore, even if the benefits of its employment in CRC mass screening have not fully established yet, CT colonography may represent a reasonable alternative screening test in patients who cannot undergo or refuse colonoscopy. Therefore, the purpose of our review is to illustrate the most updated recommendations on methodology and the current clinical indications of CT colonography, according to the data of the existing relevant literature.

CT colonography with rectal iodine tagging: Feasibility and comparison with oral tagging in a colorectal cancer screening population.

PURPOSE: To evaluate feasibility, diagnostic performance, patient acceptance, and overall examination time of CT colonography (CTC) performed through rectal administration of iodinated contrast material. MATERIALS AND METHODS: Six-hundred asymptomatic subjects (male:female=270:330; mean 63 years) undergoing CTC for colorectal cancer screening on an individual basis were consecutively enrolled in the study. Out of them, 503 patients (group 1) underwent CTC with rectal tagging, of which 55 had a total of 77 colonic lesions. The remaining 97 patients (group 2) were randomly selected to receive CTC with oral tagging of which 15 had a total of 20 colonic lesions. CTC findings were compared with optical colonoscopy, and per-segment image quality was visually assessed using a semi-quantitative score (1=poor, 2=adequate, 3=excellent). In 70/600 patients (11.7%), CTC was performed twice with both types of tagging over a 5-year follow-up cancer screening program. In this subgroup, patient acceptance was rated via phone interview two weeks after CTC using a semi-quantitative scale (1=poor, 2=fair, 3=average, 4=good, 5=excellent). RESULTS: Mean per-polyp sensitivity, specificity, positive and negative predictive values of CTC with rectal vs oral tagging were 96.1% (CI95% 85.4÷99.3%) vs 89.4% (CI95% 65.4÷98.1%), 95.3% (CI95% 90.7÷97.8%) vs 95.8% (CI95% 87.6÷98.9%), 86.0% (CI95% 73.6÷93.3) vs 85.0% (CI95% 61.1÷96.0%), and 98.8% (CI95% 95.3÷99.8%) vs 97.2% (CI95% 89.4÷99.5%), respectively (p>0.05). Polyp detection rates were not statistically different between groups 1 and 2 (p>0.05). Overall examination time was significantly shorter with rectal than with oral tagging (18.3±3.5 vs 215.6±10.3 minutes, respectively; p<0.0001). CONCLUSIONS: Rectal iodine tagging can be an effective alternative to oral tagging for CTC with the advantages of greater patient acceptance and lower overall examination time.

Bowel preparation for CT colonography.

Bowel preparation represents an essential part of CT colonography, as the accuracy of the exam is strongly related to the adequacy of colonic cleansing, and a poor bowel preparation may compromise the diagnostic quality even despite optimization of all other acquisition parameters. Residual stool and fluid in the large bowel may affect the interpretation of the exam and may increase the number of false positives and false negatives. In this regard, the majority of patients having undergone CT colonography state that bowel preparation is the most unpleasant part. Unfortunately, to date no definite consensus has been reached about the ideal bowel preparation technique, and there is great variability in preparation strategies across diagnostic centers. The purpose of this review article is to describe the development and evolution of bowel preparation techniques in order to choose the best approach for optimizing the diagnostic quality of CT colonography in each patient.

How to read and report CTC.

Owing to encouraging results achieved in the clinical practice, CT colonography (CTC) is being increasingly employed for the examination of the whole colon and rectum and is quickly becoming a widely accepted diagnostic technique that is replacing double contrast barium enema and appears a promising tool for colorectal cancer screening as well. The increasing number of symptomatic and asymptomatic patients undergoing CTC for both evaluation of symptoms and colorectal cancer screening, along with the growing availability of CTC facilities in most healthcare departments and imaging centres, requires that a sufficient number of radiologists be adequately trained in performing and interpreting CTC studies. Indeed, optimal performance of CTC depends on a number of factors, including the quality of colonic preparation (e.g. laxative bowel cleansing and optimised colonic distension), the CTC image acquisition protocol used, and reading approach and specific skills of radiologists for correct detection and interpretation of colonic findings. Consequently, dedicated training and expertise is key to obtain high sensitivity in lesion detection and reduce the number of false positives, thus ensuring an optimal clinical management of patients. To this purpose, dedicated training programmes are essential to teach and standardise not only the approach to CTC reading, but also reporting of colonic findings.

Giant fibrovascular polyp of the esophagus-imaging techniques for proper treatment planning: report of two cases.

Giant fibrovascular polyps of the esophagus are rare, benign mesenchymal intraluminal lesions that arise from the cervical esophagus and can reach a very large size. Surgical excision is the treatment of choice, since endoscopic removal alone is not always feasible due to the presence of a very much vascularized stalk in most cases. We present two archetypal cases emphasizing the fact that these lesions can grow to huge masses with various and bizarre clinical presentation and they can arise (although rarely) at the level of the hypopharynx. We also aim to point out the role of imaging in defining the exact origin and characteristics of the stalk (width, vascularization) and the polyp structure (tissue components), thus providing useful information for planning the most appropriate surgical approach.