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MR perfusion

Jun Yang, Chengde Liao, Yifan Liu, Guangjun Yang, Tengfei Ke, Yingying Ding, Qinqing Li
The beginning and the end of the vascular normalization window are not clear in response to anti-angiogenic therapies. We used dynamic contrast-enhanced MRI (DCE-MRI) and intravoxel incoherent motion MRI (IVIM-MRI) to noninvasively evaluate the vascular normalization window. MRI was performed five times: before treatment and on the second, fourth, sixth and eighth days of treatment. Quantitative perfusion parameters were calculated at each time point, including the volume transfer coefficient (Ktrans), reverse transfer constant (Kep), pseudodiffusion coefficient (D* ) and perfusion fraction (f)...
February 23, 2018: Oncotarget
Katherine L Wright, Yun Jiang, Dan Ma, Douglas C Noll, Mark A Griswold, Vikas Gulani, Luis Hernandez-Garcia
In this study, the acquisition of ASL data and quantification of multiple hemodynamic parameters was explored using a Magnetic Resonance Fingerprinting (MRF) approach. A pseudo-continuous ASL labeling scheme was used with pseudo-randomized timings to acquire the MRF ASL data in a 2.5 min acquisition. A large dictionary of MRF ASL signals was generated by combining a wide range of physical and hemodynamic properties with the pseudo-random MRF ASL sequence and a two-compartment model. The acquired signals were matched to the dictionary to provide simultaneous quantification of cerebral blood flow, tissue time-to-peak, cerebral blood volume, arterial time-to-peak, B1 , and T1...
March 12, 2018: Magnetic Resonance Imaging
Cen Zhang, John A Detre, Scott E Kasner, Brett Cucchiara
Objective: The objective of this study is to determine whether structural features of the vertebrobasilar arterial system are related to migraine. Background: Alterations in cerebral vascular structure and function have been associated with migraine, possibly mediated by hypoperfusion and/or endothelial dysfunction triggering cortical spreading depression. Vessel tortuosity, in particular, has been associated with both altered hemodynamics and endothelial function...
2018: Frontiers in Neurology
Patrick Krumm, Stefanie Mangold, Sergios Gatidis, Konstantin Nikolaou, Felix Nensa, Fabian Bamberg, Christian la Fougère
Combined PET/MRI is a novel imaging method integrating the advances of functional and morphological MR imaging with PET applications that include assessment of myocardial viability, perfusion, metabolism of inflammatory tissue and tumors, as well as amyloid deposition imaging. As such, PET/MRI is a promising tool to detect and characterize ischemic and non-ischemic cardiomyopathies. To date, the greatest benefit may be expected for diagnostic evaluation of systemic diseases and cardiac masses that remain unclear in cardiac MRI, as well as for clinical and scientific studies in the setting of ischemic cardiomyopathies...
March 10, 2018: Japanese Journal of Radiology
Ismini C Mainta, Maria I Vargas, Sara Trombella, Giovanni B Frisoni, Paul G Unschuld, Valentina Garibotto
Multiple factors, namely amyloid, tau, inflammation, metabolic, and perfusion changes, contribute to the cascade of neurodegeneration and functional decline occurring in Alzheimer's disease (AD). These molecular and cellular processes and related functional and morphological changes can be visualized in vivo by two imaging modalities, namely positron emission tomography (PET) and magnetic resonance imaging (MRI). These imaging biomarkers are now part of the diagnostic algorithm and of particular interest for patient stratification and targeted drug development...
2018: Methods in Molecular Biology
Yoshihito Tanaka, Yusuke Inoue, Yutaka Abe, Hiroki Miyatake, Hirofumi Hata
The aim of this study was to investigate the reliability of cerebral blood flow (CBF) measurements obtained by 3D pseudo-continuous arterial spin labeling (pCASL) imaging according to imaging parameters, scanner model, and field strength. We acquired 3D pCASL images in 12 healthy volunteers using four different scanners: two 3.0 T scanners and two 1.5 T scanners. Reliability was evaluated using intraclass correlation coefficient. Our results indicate that the influence of the post-labeling delay and scanner model on CBF measurements should be taken into consideration...
March 3, 2018: Clinical Imaging
Antoine Verger, Christian P Filss, Philipp Lohmann, Gabriele Stoffels, Michael Sabel, Hans-J Wittsack, Elena Rota Kops, Norbert Galldiks, Gereon R Fink, Nadim J Shah, Karl-Josef Langen
OBJECTIVES: To compare the diagnostic performance of O-(2-18 F-fluoroethyl)-L-tyrosine (18 F-FET) PET and perfusion-weighted MR imaging (PWI) for the diagnosis of progressive or recurrent glioma. METHODS: Thirty-two pretreated gliomas (25 progressive or recurrent tumors, 7 treatment-related changes, TRC) were investigated with18 F-FET PET and PWI using a hybrid PET/MR scanner. Volumes of interest (VOIs) with a diameter of 16 mm were centered upon the maximum of abnormality in the tumor area in PET and PWI maps (rCBV, rCBF, MTT) and the contralateral unaffected hemisphere...
March 3, 2018: World Neurosurgery
Sunghoon Park, Joon-Kee Yoon, Nam-Su Chung, Sang Hyun Kim, Jinwoo Hwang, Hyun Young Lee, Kyu-Sung Kwack
OBJECTIVE: To investigate the relationship between intravoxel incoherent motion (IVIM) diffusion-weighted MR imaging (DWI) parameters and 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) metabolic parameters in patients with vertebral bone metastases. METHODS: Nineteen patients with vertebral bone metastases were retrospectively included in this institutional review board-approved study. All patients underwent IVIM DWI and 18F-FDG PET/CT before treatment...
March 6, 2018: British Journal of Radiology
Yu Liu, Yuanjun Wang, Weiqing Tang, Mengda Jiang, Kaicheng Li, Xiaofeng Tao
OBJECTIVE: To investigate the therapeutic efficacy of Iodine-125 (125 I) seeds brachytherapy to pancreatic ductal adenocarcinoma (PDAC) xenografts via multiparametric magnetic resonance imaging (MRI) analysis. MATERIALS AND METHODS: Twenty mice were implanted subcutaneously with SW-1990 PDAC xenografts. The tumor-bearing mice were randomly divided into125 I seeds group (n = 10) and blank control group (n = 10). Treatment response was monitored by diffusion-weighted magnetic resonance imaging (DW-MRI) and dynamic contrast-enhanced MRI (DCE-MRI) obtained 1 day before, 14 and 60 days after treatment...
March 5, 2018: La Radiologia Medica
Zixuan Lin, Yang Li, Pan Su, Deng Mao, Zhiliang Wei, Jay J Pillai, Abhay Moghekar, Matthias van Osch, Yulin Ge, Hanzhang Lu
PURPOSE: Many brain diseases are associated with an alteration in blood-brain barrier (BBB) and its permeability. Current methods using contrast agent are primarily sensitive to major leakage of BBB to macromolecules, but may not detect subtle changes in BBB permeability. The present study aims to develop a novel non-contrast MRI technique for the assessment of BBB permeability to water. METHODS: The central principle is that by measuring arterially labeled blood spins that are drained into cerebral veins, water extraction fraction (E) and permeability-surface-area product (PS) of BBB can be determined...
March 1, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Alexander Liu, Rohan S Wijesurendra, Joanna M Liu, Andreas Greiser, Michael Jerosch-Herold, John C Forfar, Keith M Channon, Stefan K Piechnik, Stefan Neubauer, Rajesh K Kharbanda, Vanessa M Ferreira
BACKGROUND: Novel cardiac magnetic resonance (CMR) stress T1 mapping can detect ischemia and myocardial blood volume changes without contrast agents and may be a more comprehensive ischemia biomarker than myocardial blood flow. OBJECTIVES: This study describes the performance of the first prospective validation of stress T1 mapping against invasive coronary measurements for detecting obstructive epicardial coronary artery disease (CAD), defined by fractional flow reserve (FFR <0...
March 6, 2018: Journal of the American College of Cardiology
Kuniyasu Ikeoka, Shiro Hoshida, Tetsuya Watanabe, Yukinori Shinoda, Tomoko Minamisaka, Hidetada Fukuoka, Hirooki Inui, Keisuke Ueno, Yasushi Sakata
AIM: Maximal hyperemic response, leading to examination of microvascular resistance in lower-limb lesions is not well understood. This study aimed to investigate the infrainguinal arterial physiological response through a hyperemic condition and the pathophysiological significance of microvascular resistance in peripheral artery disease. METHODS: Sixteen limbs with focal stenosis of the superficial femoral artery (SFA) and 16 control limbs were analyzed. We assessed the fractional flow reserve (FFR), vascular flow reserve (VFR), and hyperemic microvascular resistance (h-MR) of the SFA with a pressure/Doppler flow sensor-tipped combination guidewire before and after endovascular therapy (EVT)...
February 28, 2018: Journal of Atherosclerosis and Thrombosis
Alexey Surov, Leonard Leifels, Hans Jonas Meyer, Karsten Winter, Osama Sabri, Sandra Purz
AIM: To analyze associations between parameters of positron-emission tomography (PET) and histogram analysis values of dynamic contrast-enhanced (DCE) imaging in patients with head and neck squamous cell carcinoma (HNSCC). PATIENTS AND METHODS: Overall, 28 patients with primary HNSCC of different localizations were involved.18 F-FDG-PET/CT and DCE MR imaging were performed for all patients. Histogram analysis parameters of DCE MRI were calculated. Spearman's correlation coefficient was used to analyze the associations between investigated parameters...
March 2018: Anticancer Research
Yi Wei, Feifei Gao, Dandan Zheng, Zixing Huang, Min Wang, Fubi Hu, Chenyang Chen, Ting Duan, Jie Chen, Likun Cao, Bin Song
Accurate preoperative differentiation of intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC) in the setting of cirrhotic liver is of great clinical significance because the treatment and prognosis of these entities differ markedly. Through a retrospectively research, we sought to determine the diagnostic performances of intravoxel incoherent motion (IVIM) and diffusion weighted imaging (DWI) parameters in the differentiating of ICC and HCC. According to the results, we found that apparent diffusion coefficient (ADC) derived from mono-exponential model and true ADC (ADCslow ) derived from bi-exponential model can be used to distinguish the ICC and HCC, and ADCslow entailed the higher diagnostic performance than ADC...
January 30, 2018: Oncotarget
Chunmei Li, Min Chen, Ben Wan, Jingying Yu, Ming Liu, Wei Zhang, Jianye Wang
Background Although several studies have been reported on evaluating the performance of Gaussian and different non-Gaussian diffusion models on prostate cancer, few studies have been reported on the comparison of different models on differential diagnosis for prostate cancer. Purpose To compare the utility of various metrics derived from monoexponential model (MEM), biexponential model (BEM), stretched-exponential model (SEM) based diffusion-weighted imaging (DWI) and diffusion kurtosis imaging (DKI) in the differential diagnosis of prostate cancer...
January 1, 2018: Acta Radiologica
Sidsel B Laursen, Stine Finsen, Niels Marcussen, Susan E Quaggin, Pernille B L Hansen, Henrik Dimke
Aldosterone blockade confers substantial cardiovascular and renal protection. The effects of aldosterone on mineralocorticoid receptors (MR) expressed in endothelial cells (EC) within the renal vasculature have not been delineated. We hypothesized that lack of MR in EC may be protective in renal vasculature and examined this by ablating the Nr3c2 gene in endothelial cells (EC-MR) in mice. Blood pressure, heart rate and PAH clearance were measured using indwelling catheters in conscious mice. The role of the MR in EC on contraction and relaxation was investigated in the renal artery and in perfused afferent arterioles...
2018: PloS One
Yuxin Li, Weixingzi Xu, Chong Sun, Jie Lin, Jianxun Qu, Jiawen Cao, Haiqing Li, Liqin Yang
PURPOSE: To investigate the cerebral macrovascular changes as well as the relationship of large vessels and cerebral blood flow (CBF) in mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) using magnetic resonance angiography (MRA) and arterial spin labeling (ASL) perfusion MR imaging (MRI). METHODS: A total of 20 patients diagnosed with MELAS (12 males, 8 females; mean age, 23.3 years) underwent conventional MRI, time-of-flight (TOF) MRA and three dimensional ASL...
February 20, 2018: Clinical Neuroradiology
Doo-Sik Kong, Junhyung Kim, Gyuha Ryu, Hye-Jin You, Joon Kyung Sung, Yong Hee Han, Hye-Mi Shin, In-Hee Lee, Sung-Tae Kim, Chul-Kee Park, Seung Hong Choi, Jeong Won Choi, Ho Jun Seol, Jung-Il Lee, Do-Hyun Nam
Quantitative imaging biomarkers have increasingly emerged in the field of research utilizing available imaging modalities. We aimed to identify good surrogate radiomic features that can represent genetic changes of tumors, thereby establishing noninvasive means for predicting treatment outcome. From May 2012 to June 2014, we retrospectively identified 65 patients with treatment-naïve glioblastoma with available clinical information from the Samsung Medical Center data registry. Preoperative MR imaging data were obtained for all 65 patients with primary glioblastoma...
January 19, 2018: Oncotarget
Lu Guo, Ping Wang, Ranran Sun, Chengwen Yang, Ning Zhang, Yu Guo, Yuanming Feng
The diffusion and perfusion magnetic resonance (MR) images can provide functional information about tumour and enable more sensitive detection of the tumour extent. We aimed to develop a fuzzy feature fusion method for auto-segmentation of gliomas in radiotherapy planning using multi-parametric functional MR images including apparent diffusion coefficient (ADC), fractional anisotropy (FA) and relative cerebral blood volume (rCBV). For each functional modality, one histogram-based fuzzy model was created to transform image volume into a fuzzy feature space...
February 19, 2018: Scientific Reports
Yanyan Xu, Qiaoyu Xu, Hongliang Sun, Tongxi Liu, Kaining Shi, Wu Wang
PURPOSE: To evaluate the diagnostic potential of DW-MRI relative parameters for differentiation of rectal cancers with different Kirsten rat sarcoma viral oncogene homologue (KRAS) mutation status. METHODS: Fifty-one patients with rectal cancer underwent diffusion-weighted MR imaging with eight b values. ADCs (including Max-ADC, Min-ADC and Mean-ADC) and IVIM parameters (D, pure diffusion; f, perfusion fraction; D*, pseudodiffusion coefficient) were respectively calculated by mono- and bi-exponential analysis...
February 15, 2018: European Radiology
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