Accuracy of computed tomographic colonography in a nationwide multicentre trial, and its relation to radiologist expertise.

OBJECTIVE: Reports on the accuracy of computed tomographic colonography (CTC) mainly involve series from expert institutions. The aims of this study were to assess CTC accuracy in a nationwide population and to relate it to radiologist performance in their initial training. DESIGN: Nationwide multicentre trial. SETTING: Twenty-eight radiologists, working in 26 mostly academic clinical units, were involved in the study after having attended a formal specialised 2-day training session on CTC. They worked through a training set of 52 cases with automatic feedback after an attempt at each case. PATIENTS: The study enrolled 845 patients with average and high risk of colorectal cancer, 737 of whom had both complete CTC and videocolonoscopy data, which constituted the dataset. INTERVENTIONS: Patients underwent same-day CTC followed by videocolonoscopy with segmental unblinding of CTC results. MAIN OUTCOME MEASURES: Sensitivity, specificity and positive and negative predictive values for detection of polyps ≥ 6 mm in per-patient and per-lesion analyses of CTC without computer-aided detection. RESULTS: Sensitivity, specificity and positive and negative predictive values for patients with polyps ≥ 6 mm were 69% (95% CI 61% to 77%), 91% (95% CI 89% to 94%), 67% (95% CI 59% to 74%) and 92% (95% CI 90% to 94%), respectively. Univariate analysis showed that the detection rate for polyps ≥ 6 mm was linked to neither radiologist case volume nor number of polyps, but was related to sensitivity achieved in the training set. Pooled sensitivity was 72% (95% CI 63% to 80%) versus 51% (95% CI 40% to 60%) for radiologists achieving above and below median sensitivity in the training set (61%), respectively. Multivariate analysis showed that sensitivity for polyps ≥ 6 mm in the training set was the only remaining significant predictive factor for subsequent performance. CONCLUSIONS: Radiologist sensitivity CTC for detection of polyps ≥ 6 mm in training was the sole independent predictor for subsequent sensitivity in detection of such polyps.

Place of intravenous arteriography with non-numerized processing in vascular pathology and surgery. Results of 424 investigations.

424 intra-venous arteriographies with non-numerized photographic subtraction have been carried out in 304 patients. Exploration concerned supra-aortic trunks in 204 cases, abdominal aorta in 107 cases, arteries of the lower limbs in 89 cases, thoracic aorta in 19 cases and arteries of the upper limbs in 5 cases. Technique is described, indications, results, complications and limits of the method are discussed for each explored area. This method is an interesting contribution as a morphological, slightly invasive evaluation of arterial lesions when computerized systems are not available.

[Cancer of the larynx and computed x-ray tomography: exploration of the hypothyroepiglottic area and paraglottic space]. / Cancer du larynx et examen tomo-densitométrique: exploration de la loge hyo-thyro-épiglottique et de l'espace para-glottique.

Twenty patients with laryngeal cancer were explored by tomography and a CT scan. Results were compared between cases and, for operated patients, with histosurgical findings. Results of this study and a review of the literature suggest that the CT scan is the most adapted examination for exploration of the paraglottic and hypothyroepiglottic spaces, but that caution should be exercised when assessing results.