Investigative radiology
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Investigative radiology · Nov 2012
Peripheral zone prostate cancer localization by multiparametric magnetic resonance at 3 T: unbiased cancer identification by matching to histopathology.
The aim of this study was to assess the diagnostic accuracy of peripheral zone prostate cancer localization by multiparametric magnetic resonance (MR) at 3 T using segmental matching of histopathology and MR images to avoid bias by image features in selection of cancer and noncancer regions. ⋯ By selecting histopathology defined cancer and noncancer areas without influence of image contrast, this study objectively reveals that all investigated MR parameters have the ability to separate cancer from noncancer areas in the peripheral zone individually and that any combination is better than T2WI alone.
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Investigative radiology · Oct 2012
Quantitative computed tomography of the lungs and airways in healthy nonsmoking adults.
The purposes of this study were to evaluate the reference range of quantitative computed tomography (QCT) measures of lung attenuation and airway parameter measurements in healthy nonsmoking adults and to identify sources of variation in those measures and possible means to adjust for them. ⋯ Although the attenuation characteristics of normal lung differ by age and sex, these differences do not persist on multivariate analysis. Potential sources of variation in measurement of attenuation-based QCT parameters include depth of inspiration/expiration and scanner type. Tracheal air attenuation may partially correct variation because of scanner type. Sources of variation in QCT airway measurements may include age, sex, BMI, depth of inspiration, and spatial resolution.
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Investigative radiology · Sep 2012
Anti-inflammatory drug evaluation in ApoE-/- mice by ultrasmall superparamagnetic iron oxide-enhanced magnetic resonance imaging.
The renin-angiotensin system and local phagocytic activity play a major role in atherosclerotic plaque development. Treatment with irbesartan, an antagonist of angiotensin II receptor, can decrease atherosclerotic lesion formation. Iron oxide-enhanced magnetic resonance imaging (MRI) can be successfully used to evaluate the phagocytic activity in the atherosclerotic plaque in mice. In this study, we used 2 iron oxide-enhanced MRI strategies, in vivo labeling by injection of iron oxide particles and injection of in vitro labeled macrophages, to investigate the effect of irbesartan on both atherosclerotic plaque size and macrophage content in apolipoprotein (Apo) E-deficient mice. ⋯ The present study illustrates an MRI follow-up of intraplaque macrophages using in vivo labeling by iron oxide particle injection and macrophage injection after in vitro USPIO labeling in the assessment of a therapeutic effect in a mouse model of atherosclerosis. Even though in vivo labeling is not fully specific of macrophage uptake, it enabled the detection of a treatment-related reduction in the macrophage content of atherosclerotic plaques in ApoE-/- mice.
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Investigative radiology · Sep 2012
Comparative StudyThe osmolality of nonionic, iodinated contrast agents as an important factor for renal safety.
Nonionic iodinated contrast agents (CAs) can be divided into monomeric, low-osmolar, and dimeric, iso-osmolar classes. In clinical practice, renal tolerance of CAs is a concern, especially in patients with impaired renal function. With regard to renal safety, we wanted to evaluate the role of osmolality and viscosity in renal tolerance. ⋯ The present results clearly show that prolonged iodine retention and the enhanced expression of kidney injury markers are caused mainly by the explicitly higher urine viscosity induced by iodixanol. We conclude that the osmolality of low-osmolar CAs such as iopromide induces a positive diuretic effect that is responsible for rapid iodine clearance and prevents increased expression of acute injury markers in the kidney.
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Investigative radiology · Jul 2012
T2* mapping of acetabular and femoral hip joint cartilage at 3 T: a prospective controlled study.
The aim of this study was to identify the pattern of T2* values in acetabular and femoral head cartilage in morphologically normal and abnormal zones at 3 T. ⋯ In combination with a 3-T system, T2* mapping offers unique advantages such as high image resolution and the ability of 3D biochemically sensitive cartilage evaluation in the hip joint without the need for contrast medium. Given these advantages, we believe that T2* mapping is another welcome addition to the rapidly evolving era of hip cartilage biochemical imaging. Further studies are necessary that involve a diagnostic histological analysis as gold standard for comparison.