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https://www.readbyqxmd.com/read/28224171/assessment-of-liver-iron-overload-by-3%C3%A2-t-mri
#1
A Paisant, A Boulic, E Bardou-Jacquet, E Bannier, G d'Assignies, F Lainé, B Turlin, Y Gandon
PURPOSE: To evaluate the performance and limitations of the signal intensity ratio method for quantifying liver iron overload at 3 T. METHODS: Institutional review board approval and written informed consent from all participants were obtained. One hundred and five patients were included prospectively. All patients underwent a liver biopsy with biochemical assessment of hepatic iron concentration and a 3 T MRI scan with 5 breath-hold single-echo gradient-echo sequences...
February 21, 2017: Abdominal Radiology
https://www.readbyqxmd.com/read/28220365/binding-of-11-c-pittsburgh-compound-b-correlated-with-white-matter-injury-in-hypertensive-small-vessel-disease
#2
Tetsuya Hashimoto, Chiaki Yokota, Kazuhiro Koshino, Takashi Temma, Makoto Yamazaki, Satoshi Iguchi, Ryo Shimomura, Toshiyuki Uehara, Naoko Funatsu, Tenyu Hino, Kazuo Minematsu, Hidehiro Iida, Kazunori Toyoda
OBJECTIVE: (11)C-Pittsburgh compound-B ((11)C-PIB) positron emission tomography (PET) is used to visualize and quantify amyloid deposition in the brain cortex in pathological conditions such as Alzheimer's disease (AD). Intense (11)C-PIB retention is also observed in the white matter (WM) of both healthy individuals and AD patients. However, the clinical implications of this retention in brain WM have not been clarified. We investigated the relationship between the extent of white matter lesions (WMLs) and the binding potential of (11)C-PIB (BPND) in the WM in patients with hypertensive small vessel disease...
February 20, 2017: Annals of Nuclear Medicine
https://www.readbyqxmd.com/read/28217013/contributions-to-the-study-of-blood-brain-flux-using-radioactive-tracers
#3
Ioan Mureşan, Ioan Cosma
In this paper, we present an original radiocirculographic method for investigates of cerebral blood flow, which has proven to be very useful, simple, and efficient for studies of brain hemodynamics. Physical considerations on injected radioactive tracer in cardiovascular system, allowed us to state a relationship for the blood flux, F, valued as the amount of fluid-blood that traverses a vascular segment in unit time. All these theoretical facts, along with a host of remarkable clinical results, are presented in a doctoral thesis entitled "The cerebral Hemodynamics in Essential Hypertension and Arteriosclerosis" of the eminent doctor Ioan Mures,an, who died in 1984, at only 50 years old...
January 2017: World Journal of Nuclear Medicine
https://www.readbyqxmd.com/read/28216518/optimization-of-t1-weighted-imaging-parameters-in-mr-carotid-plaque-imaging-influence-for-the-quantitative-evaluation-among-different-mri-scanner-types
#4
Takanori Naka, Mitsuyuki Takahashi, Koutarou Takeda, Tarou Igarashi, Tetsukazu Hondera
Carotid artery plaques with high-signal intensity on T1 weighted image (T1 WI) are known to cause cerebral ischemic disease. Signal intensity ratio (SIR), which is calculated from T1 WI in the quantitative evaluation of plaque characterization have been used. However, the various sequences in T1 WI and difference in the sequences were utilized among institutions. Therefore, difference in sequence may influence SIR. The purpose of this study was to evaluate the optimization of T1 WI sequence in MR carotid plaque imaging...
2017: Nihon Hoshasen Gijutsu Gakkai Zasshi
https://www.readbyqxmd.com/read/28216453/quantification-of-myocardial-oxygenation-in-heart-failure-using-blood-oxygen-level-dependent-t2-magnetic-resonance-imaging-comparison-with-cardiopulmonary-exercise-test
#5
Michinobu Nagao, Yuzo Yamasaki, Satoshi Kawanami, Takeshi Kamitani, Koji Sagiyama, Taiki Higo, Tomomi Ide, Atsushi Takemura, Umiko Ishizaki, Kenji Fukushima, Yuji Watanabe, Hiroshi Honda
PURPOSE: Quantification of myocardial oxygenation (MO) in heart failure (HF) has been less than satisfactory. This has necessitated the use of invasive techniques to measure MO directly or to determine the oxygen demand during exercise using the cardiopulmonary exercise (CPX) test. We propose a new quantification method for MO using blood-oxygen-level-dependent (BOLD) myocardial T2* magnetic resonance imaging (M-T2* MRI), and investigate its correlation with CPX results. METHODS: Thirty patients with refractory HF who underwent cardiac MRI and CPX test for heart transplantation, and 24 healthy, age-matched volunteers as controls were enrolled...
February 16, 2017: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/28207657/3-tesla-kinematic-mri-of-the-cervical-spine-for-evaluation-of-adjacent-level-disease-after-monosegmental-anterior-cervical-discectomy-and-arthroplasty-results-of-2-year-follow-up
#6
Steffen K Fleck, Soenke Langner, Christian Rosenstengel, Rebecca Kessler, Marc Matthes, Jan-Uwe Müller, Inga Langner, Sascha Marx, Henry W S Schroeder
STUDY DESIGN: We prospectively evaluated adjacent disc levels after anterior cervical discectomy and arthroplasty (ACDA) using kinematic magnetic resonance imaging (MRI) and plain functional radiographs. OBJECTIVE: ACDA is an established treatment for degenerative cervical disc disease. The objective of this study was to evaluate the use of kinematic MRI for assessing the range of motion (ROM) before and after ACDA compared with plain functional radiographs and to evaluate adjacent degenerative disc disease (aDDD) at mid-term follow-up...
February 15, 2017: Spine
https://www.readbyqxmd.com/read/28202466/time-varying-auditory-gain-control-in-response-to-double-pulse-stimuli-in-harbour-porpoises-is-not-mediated-by-a-stapedial-reflex
#7
Asger Emil Munch Schrøder, Kristian Beedholm, Peter Teglberg Madsen
Echolocating animals reduce their output level and hearing sensitivity, presumably to stabilize the perceived echo intensity during target approaches. In bats this variation in hearing sensitivity is formed by a call-induced stapedial reflex that tapers off over time after the call. Here we test the hypothesis that a similar mechanism exists in toothed whales by subjecting a trained harbour porpoise to a series of double sound pulses varying in delay and frequency, while measuring the magnitudes of the evoked ABRs...
February 15, 2017: Biology Open
https://www.readbyqxmd.com/read/28202349/muscle-ultrasound-and-sarcopenia-in-older-individuals-a-clinical-perspective
#8
REVIEW
Andrea Ticinesi, Tiziana Meschi, Marco V Narici, Fulvio Lauretani, Marcello Maggio
INTRODUCTION: A precise quantitative measurement of skeletal muscle mass is fundamental for diagnosing sarcopenia in older individuals. The current techniques of assessment, including dual-energy x-ray absorptiometry (DXA), bioimpedance analysis (BIA), and magnetic resonance imaging (MRI) are either difficult to perform in everyday clinical practice or biased by concurrent clinical confounders. B-mode muscle ultrasound can be helpful in assessing muscle mass and architecture, and thus possibly useful for diagnosing or screening sarcopenia...
February 12, 2017: Journal of the American Medical Directors Association
https://www.readbyqxmd.com/read/28199932/giant-cell-tumor-of-soft-tissues-a-case-report-of-extra-articular-diffuse-type-giant-cell-tumor-of-the-quadriceps
#9
Kochbati Rateb, Ben Ghozlen Hassen, Abid Leila, Farah Faten, Daghfous Med Samir
INTRODUCTION: Giant cell tumors of soft tissue (GCTs) are a relatively rare entity. It is a distinct but uncommon group of neoplasms morphologically identical to osseous giant cell tumor. The diffuse type of extra-articular GCT arising within muscle is a rare benign soft tissue tumor with a wide spectrum of clinical presentation. PRESENTATION OF CASE: This article reports a rare case of a 44-year-old woman with a mass arising from her right thigh. MRI showed only a few areas of low T2 signal in a mass that was hyper intense to muscle...
January 26, 2017: International Journal of Surgery Case Reports
https://www.readbyqxmd.com/read/28195849/detection-and-alterations-of-acetylcarnitine-in-human-skeletal-muscles-by-1h-mrs-at-7-t
#10
Radka Klepochová, Ladislav Valkovič, Martin Gajdošík, Thomas Hochwartner, Harald Tschan, Michael Krebs, Siegfried Trattnig, Martin Krššák
OBJECTIVES: The aims of this study were to detect the acetylcarnitine resonance line at 2.13 ppm in the human vastus lateralis and soleus muscles, assess T1 and T2 relaxation times, and investigate the diurnal and exercise-related changes in absolute concentration noninvasively, using proton magnetic resonance spectroscopy at 7 T. MATERIALS AND METHODS: All measurements were performed on a 7 T whole-body Magnetom MR system with a 28-channel knee coil. Five healthy, moderately trained volunteers participated in the assessment of the detectability, repeatability, and relaxation times of acetylcarnitine...
February 10, 2017: Investigative Radiology
https://www.readbyqxmd.com/read/28195848/influence-of-indocyanine-green-on-hepatic-gd-eob-dtpa-uptake-a-proof-of-concept-study-in-mice
#11
Hiroyuki Akai, Koichiro Yasaka, Masanori Nojima, Yusuke Inoue, Kuni Ohtomo, Shigeru Kiryu
OBJECTIVES: The aim of this study was to explore the influence of indocyanine green (ICG) on hepatic uptake of gadolinium ethoxybenzyldiethylenetriaminepenta-acetic acid (Gd-EOB-DTPA). MATERIALS AND METHODS: Groups of 6 female C57BL6 mice were injected with 5 mg/kg ICG, 20 mg/kg ICG, or phosphate-buffered saline (control group) 10 minutes before the injection of Gd-EOB-DTPA; identical 3-dimensional gradient echo T1-weighted images were subsequently obtained to create time-intensity curves and to measure the peak contrast ratios (CRs) of liver parenchyma...
February 10, 2017: Investigative Radiology
https://www.readbyqxmd.com/read/28187927/value-of-shear-wave-elastography-in-the-diagnosis-of-gouty-and-non-gouty-arthritis
#12
Yuanjiao Tang, Feng Yan, Yujia Yang, Xi Xiang, Liyun Wang, Lingyan Zhang, Li Qiu
Our aim was to analyze the diagnostic performance of shear wave elastography (SWE) in the diagnosis of gouty arthritis (GA) and non-gouty arthritis (non-GA). Thirty-nine patients in the GA group and 55 patients in the non-GA group were included in the study. Based on the echo intensity of the joint lesions, the GA group was subdivided into hypo-echoic GA, slightly hyper-echoic GA and hyper-echoic GA subgroups. Quantitative SWE features were evaluated and receiver operating characteristic analysis was performed...
February 7, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28178161/longitudinal-follow-up-of-muscle-echotexture-in-infants-with-congenital-muscular-torticollis
#13
Ching-Fang Hu, Tieh-Cheng Fu, Chung-Yao Chen, Carl Pai-Chu Chen, Yu-Ju Lin, Chih-Chin Hsu
Unilateral fibrous contracture of the sternocleidomastoid (SCM) muscle is the major pathophysiology in infants with congenital muscular torticollis (CMT). Physical examination is not always sufficient to detect minimal muscle fibrosis in involved SCM muscles.A prospective study for SCM muscle fibrosis in CMT infants by quantifying echotexture and muscle thickness during the course of treatment is highlighted in the study.Convenience samples of 21 female and 29 male infants with CMT, who were 1 to 12 months old, underwent physiotherapy for at least 3 months and were followed for 4...
February 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28166492/coded-excitation-for-low-snr-pulse-echo-systems
#14
Julio Isla, Frederic Cegla
Pulse compression has been used for decades in radar, sonar, medical and industrial ultrasound. It consists in transmitting a modulated and/or coded excitation, which is then cross-correlated with the received signal such that received echoes are time-compressed, thereby increasing their intensity and hence the system resolution and signal-to-noise ratio (SNR). A central problem in pulse-echo systems is that, while longer coded excitations yield higher SNRs, the length of the coded excitation or sequence is limited by the distance between the closest reflector and the transmitter/receiver...
January 30, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28166121/neural-and-muscular-contributions-to-the-age-related-reductions-in-rapid-strength
#15
Gena R Gerstner, Brennan J Thompson, Joseph G Rosenberg, Eric J Sobolewski, Michael J Scharville, Eric D Ryan
INTRODUCTION: The purpose of this study was to investigate the age-related differences in absolute and normalized plantarflexion rate of torque development (RTD) at early (0-50 ms) and late (100-200 ms) time intervals, and to examine specific neural and muscular mechanisms contributing to these differences. METHODS: Thirty-two young (20.0±2.1 yrs) and 20 older (69.5±3.3 yrs) recreationally active men performed rapid plantarflexion isometric muscle actions to examine absolute and normalized RTD and muscle activation using electromyography (EMG) at early and late time intervals...
February 4, 2017: Medicine and Science in Sports and Exercise
https://www.readbyqxmd.com/read/28160357/quantification-of-neonatal-lung-parenchymal-density-via-ultrashort-echo-time-mri-with-comparison-to-ct
#16
Nara S Higano, Robert J Fleck, David R Spielberg, Laura L Walkup, Andrew D Hahn, Robert P Thomen, Stephanie L Merhar, Paul S Kingma, Jean A Tkach, Sean B Fain, Jason C Woods
PURPOSE: To demonstrate that ultrashort echo time (UTE) magnetic resonance imaging (MRI) can achieve computed tomography (CT)-like quantification of lung parenchyma in free-breathing, non-sedated neonates. Because infant CTs are used sparingly, parenchymal disease evaluation via UTE MRI has potential for translational impact. MATERIALS AND METHODS: Two neonatal control cohorts without suspected pulmonary morbidities underwent either a research UTE MRI (n = 5; 1...
February 3, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28160221/simultaneous-detection-of-hepatocellular-carcinoma-and-vessel-thrombus-by-using-spio-enhanced-b-tfe-with-the-t2-preparation-pulse-technique
#17
Masayuki Kanamoto, Tosiaki Miyati, Kazuki Terashima, Kei Katahira, Ryoji Ida, Daisaku Suga, Nobukazu Fuwa
The purpose of this study was to compare between superparamagnetic iron oxide (SPIO)-enhanced three-dimensional balanced turbo field-echo (B-TFE) sequence with T2 preparation pulse (T2 prep) and T2*-weighted imaging (T2*WI) for the simultaneous detection of hepatocellular carcinoma (HCC) and vessel thrombus. For 1.5-T magnetic resonance imaging, SPIO was administered to 23 patients with a portal or venous tumor thrombus, and B-TFE with T2 prep and T2*WI were acquired. Regions of interest in the B-TFE and T2*WI were selected for the tumor, liver, tumor thrombus, and vessels...
February 3, 2017: Radiological Physics and Technology
https://www.readbyqxmd.com/read/28160151/neuromelanin-mri-is-useful-for-monitoring-motor-complications-in-parkinson-s-and-park2-disease
#18
REVIEW
Taku Hatano, Ayami Okuzumi, Koji Kamagata, Kensuke Daida, Daisuke Taniguchi, Masaaki Hori, Hiroyo Yoshino, Shigeki Aoki, Nobutaka Hattori
Parkinson's disease (PD) is caused by the loss of dopaminergic neurons. Recently, specific T1-weighted magnetic resonance imaging (MRI) at 3 Tesla was reported to visualize neuromelanin (NM)-related contrast of dopaminergic neurons. Using NM-MRI, we analyzed whether disease severity and motor complications (MC) are associated with the degree of dopaminergic neuronal degeneration in the substantia nigra pars compacta (SNc) in patients with idiopathic PD (PD) and PARK2. We examined 27 individuals with PD, 11 with PARK2, and a control group of 18...
February 3, 2017: Journal of Neural Transmission
https://www.readbyqxmd.com/read/28156201/neurogenic-and-myogenic-diseases-quantitative-texture-analysis-of-muscle-us-data-for-differentiation
#19
Kazuki Sogawa, Hiroyuki Nodera, Naoko Takamatsu, Atsuko Mori, Hiroki Yamazaki, Yoshimitsu Shimatani, Yuishin Izumi, Ryuji Kaji
Purpose To assess the multiple texture features of skeletal muscles in neurogenic and myogenic diseases by using ultrasonography (US). Materials and Methods After institutional review board approval, muscle US studies of the medial head of the gastrocnemius were performed prospectively in patients with neurogenic diseases (n = 25 [18 men]; mean age, 66.0 years ± 12.3 [standard deviation]), in patients with myogenic diseases (n = 21 [12 men]; mean age, 68.3 years ± 11.5), and in healthy control subjects (n = 21 [11 men]; mean age, 70...
February 2, 2017: Radiology
https://www.readbyqxmd.com/read/28155713/t2-prepared-segmented-3d-gradient-echo-for-fast-t2-weighted-high-resolution-three-dimensional-imaging-of-the-carotid-artery-wall-at-3t-a-feasibility-study
#20
Jian Zhu, Axel Bornstedt, Nico Merkle, Naifeng Liu, Wolfgang Rottbauer, Genshan Ma, Volker Rasche
BACKGROUND: The multi-contrast assessment of the carotid artery wall has become an important diagnostic tool for the characterization of atherosclerotic plaque and vessel wall thickening. For providing the required T1-, T2-, and proton density weighted contrast, multi-slice turbo spin echo (TSE) techniques are normally applied. The straightforward extension of the TSE techniques to volumetric imaging of large sections of the carotid arteries is limited by the resulting long acquisition times...
December 28, 2016: Biomedical Engineering Online
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