Investigative radiology
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Investigative radiology · Nov 2008
Clinical TrialLesion localization in patients with a previous negative transrectal ultrasound biopsy and persistently elevated prostate specific antigen level using diffusion-weighted imaging at three Tesla before rebiopsy.
To assess the use of diffusion-weighted imaging (DWI) at 3 Tesla (T) for lesion localization in patients with a high risk of prostate cancer before a rebiopsy. ⋯ DWI in addition to T2WI at 3 T has the potential to provide important information on lesion localization in patients that had both previous negative TRUS biopsy and persistently elevated prostate specific antigen levels before a repeated biopsy.
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Investigative radiology · Nov 2008
Clinical TrialMultidetector computed tomography in reperfused acute myocardial infarction. Assessment of infarct size and no-reflow in comparison with cardiac magnetic resonance imaging.
(1) To determine the accuracy of delayed enhancement multidetector computed tomography (MDCT) in measuring the extent of acute myocardial infarct and no-reflow areas using cardiac magnetic resonance imaging (MRI) as standard of reference and (2) to define the optimum timing between injection and MDCT image acquisition to characterize infarcted myocardium and no-reflow areas after reperfusion therapy. ⋯ In ST segment elevation myocardial infarction patients contrast-enhanced MDCT is an accurate method for characterizing and sizing myocardial infarct and no-reflow. Contrast-enhanced MDCT performed 5 minutes after injection yields a higher signal-to-noise ratio and image quality than the 10 minutes time point with no difference in the extent of infarct measurement.
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Investigative radiology · Nov 2008
Diagnostic accuracy of cardiac 64-slice computed tomography in detecting atrial thrombi. Comparative study with transesophageal echocardiography and cardiac surgery.
Atrial thrombi are a potential source for cerebral and peripheral emboli. Objective of this study was to evaluate the diagnostic accuracy of 64-slice cardiac computed tomography (CT) for detection of atrial thrombi in comparison with transesophageal echocardiography (TEE) and cardiac surgery. ⋯ Cardiac ECG-gated 64-slice CT is accurate to exclude atrial thrombi, which can be applied eg, in patients before radiofrequency (RF) ablation. Left atrial appendage "filling defects" cause a high number of false positive findings, and there are radiologic features, which are helpful to differentiate them from true thrombi.
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Investigative radiology · Nov 2008
Three-dimensional ultrashort echo time imaging of solid polymers on a 3-Tesla whole-body MRI scanner.
With the introduction of ultrashort echo time (UTE) sequences solid polymeric materials might become visible on clinical whole-body magnetic resonance (MR) scanners. The aim of this study was to characterize solid polymeric materials typically used for instruments in magnetic resonance guided interventions and implants. Relaxation behavior and signal yield were evaluated on a 3-Tesla whole-body MR unit. ⋯ A variety of solid polymers can be visualized by means of clinical whole-body MR scanners and 3D ultrashort echo time (UTE) sequences. The investigated polymers differ substantially in signal yield, signal-decay, and spin-lattice relaxation time. The knowledge of the signal behavior of solid polymers on whole-body clinical MR scanners may help to select suitable polymeric materials for instruments and implants which are visible using UTE sequences.