AJR. American journal of roentgenology
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AJR Am J Roentgenol · Apr 2007
Semiquantitative assessment of first-pass renal perfusion at 1.5 T: comparison of 2D saturation recovery sequences with and without parallel imaging.
The purpose of this study was to assess the feasibility and reliability of measurements performed with true fast imaging with steady-state free precession (FISP) and turbo fast low-angle shot (FLASH) sequences with parallel imaging compared with those obtained with turbo FLASH sequences without parallel imaging in first-pass renal perfusion MRI. ⋯ It seems that at 1.5 T, turbo FLASH sequences without parallel imaging are the best approach to renal first-pass perfusion imaging.
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AJR Am J Roentgenol · Apr 2007
Findings on submillimeter MDCT are predictive of operability in chronic thromboembolic pulmonary hypertension.
The purpose of this study was to investigate whether preoperative 16-MDCT at 0.7-mm collimation can be used to predict the presence of an endarterectomy plane by depicting abnormal thickening of the walls of central pulmonary arteries in patients with chronic thromboembolic pulmonary hypertension. MDCT scans of 40 patients were reviewed retrospectively by two radiologists who were blinded to surgical findings. ⋯ The sensitivity, specificity, and accuracy of MDCT in prediction of the presence of an endarterectomy plane were 99%, 80%, and 96%. Bilateral absence of an endarterectomy plane correlated with postoperative mortality according to Fisher's exact test results (p = 0.004). Submillimeter 16-MDCT therefore may be useful in predicting operability in chronic thromboembolic pulmonary hypertension.
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AJR Am J Roentgenol · Apr 2007
Characteristics of advanced adenomas detected at CT colonographic screening: implications for appropriate polyp size thresholds for polypectomy versus surveillance.
Advanced adenomas are the primary target in colorectal screening. The purpose of this study was to delineate the prevalence and imaging characteristics of advanced adenomas detected at screening CT colonography (CTC) and the rates of invasive carcinoma and high-grade dysplasia for various polyp size categories. These observations may be a basis for formulation of polypectomy thresholds and CTC surveillance strategies. ⋯ Advanced adenomas were generally large (> or = 10 mm in size); only a small percentage were medium sized (6-9 mm). There was a very low prevalence of high-grade dysplasia and invasive carcinoma in this series, particularly in the medium-sized group of lesions. These findings lend support to the practice of CTC screening in which large polyp size is used as a surrogate measure for the possible presence of advanced histologic features and medium-sized lesions are followed with noninvasive surveillance protocols.