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The article presents a case study that involved examination of the optimal dose of allopurinol to reduce urate levels by 50 percent in hemodialysis (HD) patients. The study found that no patient had a urate reduction of 50% on any dose of allopurinol, with the maximum individual percentage reduction in urate by any patient being 45.4%. The dose of 300 mg was selected as the dose of allopurinol to be used in the study.

Purpose: To scan a volunteer population using 3.0T magnetic resonance imaging (MRI). MRI of the left ventricular (LV) structure and function in healthy volunteers has been reported extensively at 1.5T.Materials and Methods: A population of 1528 volunteers was scanned. A standardized approach was taken to acquire steady-state free precession (SSFP) LV data in the short-axis plane, and images were quantified using commercial software. Six observers undertook the segmentation analysis.Results: Mean values (±standard deviation, SD) were: ejection fraction (EF) = 69 ± 6%, end diastolic volume index (EDVI) = 71 ± 13 ml/m2 , end systolic volume index (ESVI) = 22 ± 7 ml/m2 , stroke volume index (SVI) = 49 ± 8 ml/m2 , and LV mass index (LVMI) = 55 ± 12 g/m2 . The mean EF was slightly larger for females (69%) than for males (68%), but all other variables were smaller for females (EDVI 68v77 ml/m2 , ESVI 21v25 ml/m2 , SVI 46v52 ml/m2 , LVMI 49v64 g/m2 , all P < 0.05). The mean LV volume data mostly decreased with each age decade (EDVI males: -2.9 ± 1.3 ml/m2 , females: -3.1 ± 0.8 ml/m2 ; ESVI males: -1.3 ± 0.7 ml/m2 , females: -1.7 ± 0.5 ml/m2 ; SVI males: -1.7 ± 0.9 ml/m2 , females: -1.4 ± 0.6 ml/m2 ; LVMI males: -1.6 ± 1.1 g/m2 , females: -0.2 ± 0.6 g/m2 ) but the mean EF was virtually stable in males (0.6 ± 0.6%) and rose slightly in females (1.2 ± 0.5%) with age.Conclusion: LV reference ranges are provided in this population-based MR study at 3.0T. The variables are similar to those described at 1.5T, including variations with age and gender. These data may help to support future population-based MR research studies that involve the use of 3.0T MRI scanners. J. Magn. Reson. Imaging 2016;44:1186-1196. [ABSTRACT FROM AUTHOR]

Purpose: To optimize the contrast agent dose and delivery rate used in a novel whole-body magnetic resonance angiography (MRA) protocol using a 3.0T MR scanner. Materials and Methods: Six groups of 20 consenting volunteers underwent whole-body MRA, with each group receiving a different contrast dose and contrast delivery rate. The arterial tree was divided into 16 segments and the image quality at each of the anatomical locations, covering the whole body, was assessed. Qualitative analysis was carried out using a scoring assessment of image quality, and quantitative assessments were performed by measuring contrast-to-noise (CNR) and a signal-to-noise (SNR) index. Results: Reducing the contrast dose from 40 mL to 25 mL was found to significantly increase the CNR in several vessels of interest in the arterial tree. There was also a significant increase in the qualitative image quality score ( P < 0.001). Conclusion: This study demonstrates that reducing the contrast dose at 3.0T can result in an increase in the CNR in the vessels of interest without significantly affecting the SNR. J. Magn. Reson. Imaging 2009;30:1059-1067. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Purpose To derive reproducibility assessments of ejection fraction (EF) and left ventricular mass (LVM) from short-axis cardiac MR images acquired at single and multiple time-points on different 1.5T scanner models. Materials and Methods Images of 15 healthy volunteers were acquired twice using a Magnetom Avanto scanner (Siemens, Erlangen, Germany) and once using a Signa Excite scanner (General Electric, Milwaukee, WI, USA) over four months, and analyzed using ARGUS and MASS Analysis+ software, respectively. Two physicists independently segmented the myocardial borders in order to derive intra- and interobserver assessments of EF and LVM for single and multiple time-points on the same and different scanners. Results For EF, the coefficient of repeatability (CoR) increased as different observers, multiple time-points, and different scanners were introduced. The CoR ranged from 2.8% (intraobserver measurements, single time-point, same scanner) to 10.0% (interobserver measurements, different time-points, different scanners). For LVM, intraobserver CoR parameters were consistently smaller than interobserver values. The CoR ranged from 7.8 g (intraobserver measurements, single time-point, same scanner) to 39.5 g (interobserver measurements, different time-points, different scanners). Conclusion Reproducible EF data can be obtained at single or multiple time-points using different scanners. However, LVM is notably susceptible to interobserver variation, and this should be carefully considered if similar evaluations are planned as part of multicenter or longitudinal investigations. J. Magn. Reson. Imaging 2008;28:359-365. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Mangafodipir, a manganese-containing hepatobiliary contrast agent, is excreted in bile. We review the principles and practice of a contrast-enhanced MRC technique using mangafodipir and compare it with standard T2-weighted magnetic resonance cholangiography (MRC) sequences. Potential applications include the evaluation of leaks and strictures; the assessment of drainage in normal, surgically by-passed, stented and obstructed biliary systems; the diagnosis of cholecystitis; and the evaluation of normal and variant biliary anatomy. J. Magn. Reson. Imaging 2004;20:256-263. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Purpose: To determine the effect of age, sex, and presence of carotid atheromatous disease on the presence of aortic spiral blood flow pattern using two-dimensional flow quantitative magnetic resonance imaging (MRI). Materials and Methods: Sixty subjects (37 women, 23 men) were examined. Prospective phase contrast flow quantitative MRI (1.5 T, Siemens Symphony) sequences in the plane of the aortic arch, and three-dimensional contrast-enhanced MR angiography of the vessels from the aortic arch to the circle of Willis, were performed. Flow quantitative analysis, using circular regions of interest, in the root, apex, and descending aortic arch to determine the presence of a spiral blood flow pattern was undertaken. The results were correlated with the subjects age, sex, and presence of significant carotid arterial disease. Results: A spiral blood flow pattern was seen during diastole in 43 of 50 (86%), 42 of 48 (88%), and in 26 of 28 (93%) subjects in the root, apex, and descending aortic arch, respectively. Spiral flow was seen during systole in 14 of 35 (40%), 20 of 47 (42%), and 11 of 31 (35%) subjects in the root, apex, and descending aortic arch, respectively. There was no clear effect of age or sex on the presence of spiral flow. Carotid disease was associated with a significant reduction in the prevalence of systolic spiral flow from 51%-19% subjects ( P < 0.05). Conclusion: Spiral flow pattern can be seen in the arch of the aorta in clinical practice using flow quantitative MRI. The prevalence of spiral flow pattern does not appear affected by subject age or sex. Carotid atheromatous disease is associated with a reduction in prevalence of systolic spiral flow pattern in the aortic arch. J. Magn. Reson. Imaging 2003;18:169-174. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The cover image is based on the Research Article Morphological and hemodynamical alterations in brachial artery and cephalic vein. An image‐based study for preoperative assessment for vascular access creation by Nicolas Aristokleous et al., https://doi.org/10.1002/cnm.3136. [ABSTRACT FROM AUTHOR]

The current study aims to computationally evaluate the effect of right upper arm position on the geometric and hemodynamic characteristics of the brachial artery (BA) and cephalic vein (CV) and, furthermore, to present in detail the methodology to characterise morphological and hemodynamical healthy vessels. Ten healthy volunteers were analysed in two configurations, the supine (S) and the prone (P) position. Lumen 3D surface models were constructed from images acquired from a non‐contrast MRI sequence. Then, the models were used to numerically compute the physiological range of geometric (n = 10) and hemodynamic (n = 3) parameters in the BA and CV. Geometric parameters such as curvature and tortuosity, and hemodynamic parameters based on wall shear stress (WSS) metrics were calculated with the use of computational fluid dynamics. Our results highlight that changes in arm position had a greater impact on WSS metrics of the BA by altering the mean and maximum blood flow rate of the vessel. Whereas, curvature and tortuosity were found not to be significantly different between positions. Inter‐variability was associated with antegrade and retrograde flow in BA, and antegrade flow in CV. Shear stress was low and oscillatory shear forces were negligible. This data suggests that deviations from this state may contribute to the risk of accelerated intimal hyperplasia of the vein in arteriovenous fistulas. Therefore, preoperative conditions coupled with post‐operative longitudinal data will aid the identification of such relationships. This study highlighted that changes in arm position had a greater impact on wall shear stress metrics of the brachial artery by altering the mean and maximum blood flow rate. Whereas, curvature and tortuosity were found not to be significantly different between positions. Moreover, the image‐based computational fluid dynamics analysis highlighted an inter‐variability of shear stress metrics within a small sample of healthy subjects which lead to the postulation that deviations from homeostatic conditions will modulate remodelling rather than exceeding a global threshold. [ABSTRACT FROM AUTHOR]