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BACKGROUND Turner syndrome (TS) is associated with aortic coarctation and dissection; hence, echocardiographic evaluation of all patients is currently recommended. X-ray angiography in clinically symptomatic patients has suggested a range of other vascular anomalies, but the true prevalence of such lesions in TS is unknown. To better understand the(More)
The chemical shift phenomenon refers to the signal intensity alterations seen in magnetic resonance (MR) imaging that result from the inherent differences in the resonant frequencies of precessing protons. Chemical shift was first recognized as a misregistration artifact of image data. More recently, however, chemical shift has been recognized as a useful(More)
Bolus chase 3-dimensional MR angiography (3D MRA) is a recent development that extends the effective field of view for arterial imaging from the typical single 40-50 cm to over 100 cm. This technique is well suited for imaging long vascular territories such as the lower extremity. Bolus chase peripheral 3D MRA is achieved with overlapping 3D gradient-echo(More)
Peripheral magnetic resonance angiography (MRA) is growing in use. However, methods of performing peripheral MRA vary widely and continue to be optimized, especially for improvement in illustration of infrapopliteal arteries. The main purpose of this project was to identify imaging factors that can improve arterial visualization in the lower leg using bolus(More)
In this pilot study, using a standard 40 mL gadolinium (Gd) chelate contrast dose, dual-rate (first 20 mL at 0.5 mL/sec; remaining 20 mL at 1.5 mL/sec) and fixed-rate (entire 40 mL dose at either 0.7 mL/sec or 2.0 mL/sec) injection schemes for multistation, bolus-chase magnetic resonance angiography (MRA) were compared in normal volunteers. Signal-to-noise(More)
PURPOSE To establish a quantitative magnetic resonance (MR) imaging contrast enhancement criterion for distinguishing cysts from solid renal lesions. MATERIALS AND METHODS Regions of interest were measured in 74 patients with renal lesions evaluated by means of dynamic contrast material-enhanced MR imaging with serial breath-hold spoiled gradient-echo(More)
Contrast-enhanced MR angiography (CE-MRA) using steady-state free precession (SSFP) pulse sequences is described. Using SSFP, vascular structures can be visualized with high signal-to-noise ratio (SNR) at a substantial (delay) time after the initial arterial pass of contrast media. The peak blood SSFP signal was diminished by <20% 30 min after the initial(More)
PURPOSE To investigate the feasibility of preferential arterial imaging using gadolinium-enhanced thick-slice phase-contrast imaging. METHODS Six healthy volunteers were studied using a peripheral-gated segmented k-space CINE phase-contrast pulse sequence using four views per RR interval with flow encoding in the superior-inferior direction. Images at the(More)
A new method was investigated for improving the efficiency of ECG-gated coronary magnetic resonance angiography (CMRA) by accurate, automated tracking of the vessel motion over the cardiac cycle. Vessel tracking was implemented on a spiral gradient-echo pulse sequence with sub-millimeter in-plane spatial resolution as well as high image signal to noise(More)
A method of three-station three-dimensional magnetic resonance (MR) angiography of the lower extremities with segmented volume acquisition is presented. Three-dimensional MR angiographic data were acquired in two passes, with the central k-space views acquired during the arterial phase for the more proximal stations. This allowed a faster bolus injection(More)