Contrast medium uptake rate obtained at D-MRI represents a reproducible parameter that is reliable for predicting and monitoring treatment outcome in acute Charcot foot.

Our aim is to compare the radiation dose associated with a low-dose CT colonography (CTC) protocol for colorectal cancer screening with that delivered by double-contrast barium enema (DCBE). CTC of twenty asymptomatic individuals (M:F = 10:10) participating to a colorectal cancer screening program and DCBE of fifteen patients (M:F = 6:9) were evaluated. For CTC, absorbed dose was determined by calculating the dose-length product for each CTC examination from measurements on a CT dose phantom equipped with a CT ion chamber. For DCBE, the free-in-air Kerma at the patient's X-ray entry surface and the Kerma-area product during fluoroscopy and fluorography were measured with a Barracuda system, with fluoroscopy times being recorded blinded to the performing operator. Effective dose at CTC was 2.17 ± 0.12 mSv, with good and excellent image quality in 14/20 (70%) and 6/20 cases (30%), respectively. With DCBE, effective patient dose was 4.12 ± 0.17 mSv, 1.9 times greater than CTC (P < 0.0001). Our results show that effective dose from screening CTC is substantially lower than that from DCBE, suggesting that CTC is the radiological imaging technique of the large bowel with the lowest risk of stochastic radiation effects.

Once presence of a colorectal cancer has been diagnosed, a key factor for patient's prognosis in view of surgical intervention is the correct segmental localization and resection of the tumor. The aim of this work was to compare the accuracy of the current gold standard technique, conventional colonoscopy (CC), to computed tomography colonography (CTC) in the segmental localization of tumor. Sixty-five patients (mean age 64; 45 female and 19 male) with colorectal cancer diagnosed at colonoscopy underwent CTC before surgery. In 45 out of 65 cases (69%), patients were referred to CTC after incomplete CC. Reasons were patient intolerance to CC or presence of stenosing cancer, with consistent difficulties in crossing the tract of the colon involved by the lesion. CTC allowed the complete colonic examination in 63/65 cases, since in 2 patients with an obstructing lesion of the sigmoid colon, pneumocolon could not be obtained. However, per patient and per lesion sensitivity of CTC was 100%. Difference from colonoscopy was statistically significant (P < 0.05). In terms of segmental localization of masses, CTC located precisely all lesions, while colonoscopy failed in 16/67 (24%) lesions, though six were missed for incomplete colonoscopy (9%). In the remaining 10/67 (15%) lesions, detected by colonoscopy but incorrectly located, the mismatch occurred in the rectum (n = 3), sigmoid (n = 2), descending (n = 1), transverse (n = 2), ascending colon, and cecum. Agreement between CTC and CC was fair (k value 0.62). Sensitivity, specificity, positive predictive value and negative predictive value of CTC in determining the precise location of colonic masses were respectively 100%, 96%, 85%, and 100%. CT detected hepatic (6/65 patients) and lung metastases (3/65 patients). CT colonography has better performance in the identification of colonic masses (diameter > 3 cm), in the completion of colonic evaluation and in the segmental localization of tumor. CTC should replace colonoscopy for preoperative staging of colorectal cancer.

The purpose of the study was to test the tagging performance and patient's acceptance of a reduced cathartic preparation, based on iodixanol and PEG, administered to patients 3 h before the exam. One hundred and thirty-two asymptomatic patients were enrolled. As colonic cleansing we used PEG macrogol 3350. For fluid tagging iodixanol was orally administered 3 h before the exam, in a total dose of 50 mL mixed with 34.8 g of PEG in 750 mL of water. Image's review showed 446 segments (56.4%) clean of feces and 346 segments (43.6%) with feces. Untagged fluid was observed in 74/706 (10.5%) segments; inhomogeneous tagging in 129/706 (16%); the average density of fluid was 1054.74 UH in the cecum-ascending colon and 905.14 UH in the descending-sigmoid colon; the average difference of density between right and left colonic segments was 149 UH, and it was statistically significant (P = 0.016). No side effects related to the consumption of Movicol were reported. Very few side effects related to the tagging solution were reported: mild nausea in 7 (0.05%) patients, mild diarrhea in 10 (0.07%). An average rank of 9 points (SD +/- 1) on a 10-point scale (10 = no discomfort, 0 = severe discomfort) resulted from the self-administered questionnaire, showing an excellent acceptance of the preparation. Same day fluid tagging with iodixanol provides an optimal fluid tagging, it is completely tolerated by the patient, and it can be performed under medical control.