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https://www.readbyqxmd.com/read/28633793/treatment-of-a-focal-articular-cartilage-defect-of-the-talus-with-polymer-based-autologous-chondrocyte-implantation-a-12-year-follow-up-period
#1
Peter Cornelius Kreuz, Richard Horst Kalkreuth, Philipp Niemeyer, Markus Uhl, Christoph Erggelet
Autologous chondrocyte implantation (ACI) is a first-line treatment option for large articular cartilage defects. Although well-established for cartilage defects in the knee, studies of the long-term outcomes of matrix-assisted ACI to treat cartilage defects in the ankle are rare. In the present report, we describe for the first time the long-term clinical and radiologic results 12 years after polymer-based matrix-assisted ACI treat a full-thickness talar cartilage defect in a 25-year-old male patient. The clinical outcome was assessed using the visual analog scale and Freiburg ankle score, magnetic resonance imaging evaluation using the Henderson-Kreuz scoring system and T2 mapping...
July 2017: Journal of Foot and Ankle Surgery: Official Publication of the American College of Foot and Ankle Surgeons
https://www.readbyqxmd.com/read/28631203/assessment-of-mri-contrast-agent-concentration-by-quantitative-susceptibility-mapping-qsm-application-to-estimation-of-cerebral-blood-volume-during-steady-state
#2
Emelie Lind, Linda Knutsson, Robin Kämpe, Freddy Ståhlberg, Ronnie Wirestam
OBJECTIVE: One major issue in dynamic susceptibility contrast MRI (DSC-MRI) is to accurately determine contrast agent (CA) concentration, since T2* relaxivity in vivo is generally unknown and varies between blood and tissue. In this study, quantitative susceptibility mapping (QSM) was used for quantification of CA concentration. MATERIALS AND METHODS: A DSC-MRI protocol, including phase data acquisition, was applied to 20 healthy volunteers in a test-retest study...
June 19, 2017: Magma
https://www.readbyqxmd.com/read/28629954/high-resolution-myelin-water-imaging-incorporating-local-tissue-susceptibility-analysis
#3
Zhe Wu, Hongjian He, Yi Sun, Yiping Du, Jianhui Zhong
Quantitative myelin water imaging (MWI) from signal T2* decay acquired with multiple Gradient-Recalled Echo (mGRE) sequence has been widely used since its first report. A recent study showed that with low resolution data (2mm isotropic voxels), direct application of complex fitting to a three-pool WM model with frequency shift terms could produce more stable parameter estimation for myelin water fraction mapping. MWI maps of higher spatial resolution resulting in more detailed tissue structures and reduced partial volume effects around white matter/gray matter (WM/GM) interface, however, is more desirable...
June 16, 2017: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/28614221/correlation-of-mdr1-gene-polymorphisms-with-anesthetic-effect-of-sevoflurane-remifentanil-following-pediatric-tonsillectomy
#4
Nian-Jun Shi, Wei-Xia Zhang, Ning Zhang, Li-Na Zhong, Ling-Ping Wang
BACKGROUND: The motive of this study was to investigate the collaboration between MDR1 gene polymorphisms and anesthetic effects following pediatric tonsillectomy. METHODS: All together 178 children undergoing tonsillectomy with preoperative sevoflurane-remifentanil anesthesia were selected. In order to determine MDR1 gene polymorphisms of 3435C > T, 1236C > T, and 2677G > T/A, polymerase chain reaction-restriction fragment length polymorphism was used...
June 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28611637/a-case-of-posterior-reversible-encephalopathy-syndrome-induced-by-cisplatin-pemetrexed-chemotherapy-for-lung-cancer
#5
Masashi Ishihara, Noriyuki Matsutani, Shuji Ota, Nobuhiko Seki
This report presents the case of a 60-year-old woman who was diagnosed with stage IV lung adenocarcinoma with asymptomatic brain metastases and commenced chemotherapy with cisplatin/pemetrexed (CDDP/Pem). She experienced tonic-clonic convulsions on day 9 of the first cycle, which were accompanied by increased blood pressure (173/69 mm Hg) and headache. Therefore, brain MRI was performed to check for stroke or progression of brain metastatic foci. T2-weighted, FLAIR, and ADC map images showed high-intensity areas in the subcortical region of the bilateral parieto-occipital lobes, leading to a diagnosis of posterior reversible encephalopathy syndrome (PRES)...
January 2017: Case Reports in Oncology
https://www.readbyqxmd.com/read/28606578/a-case-of-ecchordosis-physaliphora-in-the-prepontine-cistern-a-rare-entity-in-the-differential-diagnosis-of-an-epidermoid-cyst
#6
Kenji Miki, Koji Yoshimoto, Ataru Nishimura, Satoshi O Suzuki, Akio Hiwatashi, Koji Iihara
BACKGROUND: Ecchordosis physaliphora (EP) is a benign notochordal remnant, which is usually asymptomatic. Herein, we report a case of symptomatic large EP mimicking an epidermoid cyst. CASE DESCRIPTION: A 44-year-old female presented with right facial dysesthesia. Brain magnetic resonance imaging (MRI) showed a mass with a diameter of 3.2 cm that was hypointense on T1-weighted images (T1WI), hyperintense on T2-weighted images (T2WI), iso-to-hyperintense on diffusion-weighted (DW) images, and hyperintense on apparent diffusion coefficient (ADC) map (1...
June 9, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28604062/cartilage-regeneration-in-full-thickness-patellar-chondral-defects-treated-with-particulated-juvenile-articular-allograft-cartilage-an-mri-analysis
#7
Brian Grawe, Alissa Burge, Joseph Nguyen, Sabrina Strickland, Russell Warren, Scott Rodeo, Beth ShubinStein
Background Full-thickness cartilage lesions of the patella represent a common source of pain and dysfunction. Previously reported surgical treatment options include marrow stimulation, cell-based treatments, and osteochondral transfer. Minced juvenile allograft cartilage is a novel treatment option that allows for a single stage approach for these lesions. Hypothesis Particulated juvenile allograft cartilage (PJAC) for the treatment of chondral defects of the patella would offer acceptable lesion fill rates, mature over time, and not be associated with any negative biologic effects on the surrounding tissue...
June 1, 2017: Cartilage
https://www.readbyqxmd.com/read/28602814/quantitative-in-vivo-t2-mapping-using-fast-spin-echo-techniques-a-linear-correction-procedure
#8
Ulrike Nöth, Manoj Shrestha, Jan-Rüdiger Schüre, Ralf Deichmann
A method is presented for correcting the effects of stimulated and indirect echoes on quantitative T2 mapping data acquired with multiple spin echo techniques, such as turbo spin echo. In contrast to similar correction techniques proposed in the literature, the method does not require a priori knowledge of the radio frequency (RF) pulse profiles. In a first step, for the T2 mapping protocol under investigation, signal decay curves S(TE) are simulated for a range of different RF pulse profiles. The actual signal decay S(TE) is then measured on a phantom with known T2, so the approximate RF pulse profiles can be derived via comparison with the simulated decay curves...
June 8, 2017: NeuroImage
https://www.readbyqxmd.com/read/28602813/automated-segmentation-of-midbrain-structures-with-high-iron-content
#9
REVIEW
Benjamín Garzón, Rouslan Sitnikov, Lars Bäckman, Grégoria Kalpouzos
The substantia nigra (SN), the subthalamic nucleus (STN), and the red nucleus (RN) are midbrain structures of ample interest in many neuroimaging studies, which may benefit from the availability of automated segmentation methods. The high iron content of these structures awards them high contrast in quantitative susceptibility mapping (QSM) images. We present a novel segmentation method that leverages the information of these images to produce automated segmentations of the SN, STN, and RN. The algorithm builds a map of spatial priors for the structures by non-linearly registering a set of manually-traced training labels to the midbrain...
June 9, 2017: NeuroImage
https://www.readbyqxmd.com/read/28601627/effects-of-small-dose-dexmedetomidine-on-hyperdynamic-responses-to-electroconvulsive-therapy
#10
Xiang Li, Fang Tan, Chao-Jun Jian, Na Guo, Zhi-Yong Zhong, Zi-Qing Hei, Shao-Li Zhou
BACKGROUND: Acute hemodynamic responses to electroconvulsive therapy (ECT) may increase the risk of cardiovascular complications in vulnerable patients. The aim of the current study was to assess the effect of small-dose dexmedetomidine on hyperdynamic responses to ECT. METHODS: Seventy-eight patients were enrolled and randomly allocated to receive either 0.2 μg/kg dexmedetomidine (Dex group, n = 39) or saline (Control group, n = 39) prior to ECT. Heart rate (HR) and mean arterial pressure (MAP) were recorded immediately after the administration of dexmedetomidine (T1), and 0, 1, 3, 5 and 10 min after the electrical stimuli ended (T2, T3, T4, T5 and T6)...
June 7, 2017: Journal of the Chinese Medical Association: JCMA
https://www.readbyqxmd.com/read/28599415/value-of-diffusion-weighted-magnetic-resonance-imaging-in-predicting-world-health-organization-grade-in-g1-g2-pancreatic-neuroendocrine-tumors
#11
Chuangen Guo, Xiaoling Zhuge, Xiao Chen, Zhongqiu Wang, Wenbo Xiao, Qidong Wang
The present study aimed to investigate the value of diffusion-weighted magnetic resonance imaging (DWI) in the grading of well-differentiated pancreatic neuroendocrine tumors (PanNETs). A total of 44 patients with histologically proven well-differentiated PanNET [grade 1 (G1) and grade 2 (G2) according to the World Health Organization (WHO) criteria] underwent pretreatment magnetic resonance imaging (MRI), which was retrospectively analyzed. The location, size, cystic or solid appearance, boundary, presence or absence of tumor contrast enhancement, and MRI signal of the tumor were assessed...
June 2017: Oncology Letters
https://www.readbyqxmd.com/read/28590821/t2-mapping-of-the-sacroiliac-joints-with-3-t-mri-a-preliminary-study
#12
Guillaume Lefebvre, Antonin Bergère, Mazen El Rafei, Alain Duhamel, Pedro Teixeira, Anne Cotten
OBJECTIVE: The objective of this study was to assess the feasibility of T2 relaxation time measurements of the sacroiliac joints. SUBJECTS AND METHODS: The sacroiliac joints of 40 patients were imaged by 3-T MRI using an oblique axial multislice multiecho spin-echo T2-weighted sequence. Manual plotting and automatic subdivision of ROIs allowed us to obtain T2 values for up to 48 different areas per patient (posterior and anterior parts, sacral, intermediate, and iliac parts)...
June 7, 2017: AJR. American Journal of Roentgenology
https://www.readbyqxmd.com/read/28587365/assessment-of-different-loading-doses-of-dexmedetomidine-hydrochloride-in-preventing-adverse-reaction-after-combined-spinal-epidural-anesthesia
#13
Wanwei Jiang, Qinghui Wang, Min Xu, Yu Li, Rui Yang, Xiaoyang Song, Haixia Duan, Pengbo Zhang
We conducted the present study to investigate the effects of the different loading doses of dexmedetomidine hydrochloride in the prevention of adverse reactions after combined spinal-epidural anesthesia. A total of 200 patients that were admitted to the Department of Obstetrics at the Second Affiliated Hospital of Xi'an Jiaotong University hospital and treated with cesarean section through the use of combined spinal-epidural anesthesia from December, 2014 to June, 2016, were randomly divided into 4 groups. The therapeutic regimens of patients were shown as follows: group A was administered an intravenous pump of 10 ml/l physiological saline in surgery until the end of the delivery...
June 2017: Experimental and Therapeutic Medicine
https://www.readbyqxmd.com/read/28585238/three-dimensional-mapping-of-brain-venous-oxygenation-using-r2-oximetry
#14
Deng Mao, Yang Li, Peiying Liu, Shin-Lei Peng, Jay J Pillai, Hanzhang Lu
PURPOSE: Cerebral venous oxygenation (Yv ) is an important biomarker for brain diseases. This study aims to develop an R2*-based MR oximetry that can measure cerebral Yv in 3D. METHODS: This technique separates blood signal from tissue by velocity-encoding phase contrast and measures the R2* of pure blood by multi-gradient-echo acquisition. The blood R2* was converted to Yv using an R2*-versus-oxygenation (Y) calibration curve, which was obtained by in vitro bovine blood experiments...
June 6, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28585150/mild-encephalopathy-encephalitis-with-a-reversible-splenial-lesion-mers-a-report-of-five-neonatal-cases
#15
Dan Sun, Wen-Hong Chen, Suraj Baralc, Juan Wang, Zhi-Sheng Liu, Yuan-Peng Xia, Lei Chen
Mild encephalopathy/encephalitis with a reversible splenial (MERS) lesion is a clinic-radiological entity. The clinical features of MERS in neonates are still not systemically reported. This paper presents five cases of MERS, and the up-to-date reviews of previously reported cases were collected and analyzed in the literature. Here we describe five cases clinically diagnosed with MERS. All of them were neonates and the average age was about 4 days. They were admitted for the common neurological symptoms such as hyperspasmia, poor reactivity and delirium...
June 2017: Journal of Huazhong University of Science and Technology. Medical Sciences
https://www.readbyqxmd.com/read/28583638/a-phase-i-clinical-trial-of-the-knee-to-assess-the-correlation-of-gagcest-mri-delayed-gadolinium-enhanced-mri-of-cartilage-and-t2-mapping
#16
Wenbo Wei, Becky Lambach, Guang Jia, Christopher Kaeding, David Flanigan, Michael V Knopp
PURPOSE: Osteoarthritis (OA) is associated with the loss of glycosaminoglycan (GAG) during disease progression, which can be detected by glycosaminoglycan chemical exchange-dependent saturation transfer (gagCEST) MRI. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) is considered one of the standard methods for GAG quantification in vivo. This Phase I study assessed the correlation between gagCEST MRI and dGEMRIC in determining cartilage GAG concentration. Standard T2 mapping was used as a comparator with the two other methods...
May 2017: European Journal of Radiology
https://www.readbyqxmd.com/read/28573638/peribiliary-liver-metastases-mr-findings
#17
Vincenza Granata, Roberta Fusco, Orlando Catalano, Antonio Avallone, Maddalena Leongito, Francesco Izzo, Antonella Petrillo
We described magnetic resonance (MR) features of peribiliary metastasis and of periductal infiltrative cholangiocarcinoma. We assessed 35 patients, with peribiliary lesions, using MR 4-point confidence scale. T1-weighted (T1-W), T2-weighted (T2-W) and diffusion-weighted images (DWI) signal intensity, enhancement pattern during arterial, portal, equilibrium and hepatobiliary phase were assessed. We identified 24 patients with periductal-infiltrating cholangiocellular carcinoma. The lesions in 34 patients appeared as a single tissue, while in a single patient, the lesions appeared as multiple individual lesions...
July 2017: Medical Oncology
https://www.readbyqxmd.com/read/28570641/correlation-study-between-facet-joint-cartilage-and-intervertebral-discs-in-early-lumbar-vertebral-degeneration-using-t2-t2-and-t1%C3%AF-mapping
#18
Yi Zhang, Jianzhong Hu, Chunyue Duan, Ping Hu, Hongbin Lu, Xianjing Peng
Recent advancements in magnetic resonance imaging have allowed for the early detection of biochemical changes in intervertebral discs and articular cartilage. Here, we assessed the feasibility of axial T2, T2* and T1ρ mapping of the lumbar facet joints (LFJs) to determine correlations between cartilage and intervertebral discs (IVDs) in early lumbar vertebral degeneration. We recruited 22 volunteers and examined 202 LFJs and 101 IVDs with morphological (sagittal and axial FSE T2-weighted imaging) and axial biochemical (T2, T2* and T1ρ mapping) sequences using a 3...
2017: PloS One
https://www.readbyqxmd.com/read/28569645/in-vivo-evidence-of-oxidative-stress-in-brains-of-patients-with-progressive-multiple-sclerosis
#19
In-Young Choi, Phil Lee, Peter Adany, Abbey J Hughes, Scott Belliston, Douglas R Denney, Sharon G Lynch
BACKGROUND: The oxidative stress hypothesis links neurodegeneration in the later, progressive stages of multiple sclerosis (MS) to the loss of a major brain antioxidant, glutathione (GSH). OBJECTIVE: We measured GSH concentrations among major MS subtypes and examined the relationships with other indices of disease status including physical disability and magnetic resonance imaging (MRI) measures. METHODS: GSH mapping was performed on the fronto-parietal region of patients with relapsing-remitting multiple sclerosis (RRMS, n = 21), primary progressive multiple sclerosis (PPMS, n = 20), secondary progressive multiple sclerosis (SPMS, n = 20), and controls ( n = 28) using GSH chemical shift imaging...
June 1, 2017: Multiple Sclerosis: Clinical and Laboratory Research
https://www.readbyqxmd.com/read/28569617/multimodal-partial-volume-correction-application-to-11-c-pib-pet-mri-myelin-imaging-in-multiple-sclerosis
#20
Elisabetta Grecchi, Mattia Veronese, Benedetta Bodini, Daniel García-Lorenzo, Marco Battaglini, Bruno Stankoff, Federico E Turkheimer
The [(11)C]PIB PET tracer, originally developed for amyloid imaging, has been recently repurposed to quantify demyelination and remyelination in multiple sclerosis (MS). Myelin PET imaging, however, is limited by its low resolution that deteriorates the quantification accuracy of white matter (WM) lesions. Here, we introduce a novel partial volume correction (PVC) method called Multiresolution-Multimodal Resolution-Recovery (MM-RR), which uses the wavelet transform and a synergistic statistical model to exploit MRI structural images to improve the resolution of [(11)C]PIB PET myelin imaging...
January 1, 2017: Journal of Cerebral Blood Flow and Metabolism
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