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Microscopic coil Mri

Ryan L Brunsing, Natalie M Schenker-Ahmed, Nathan S White, J Kellogg Parsons, Christopher Kane, Joshua Kuperman, Hauke Bartsch, Andrew Karim Kader, Rebecca Rakow-Penner, Tyler M Seibert, Daniel Margolis, Steven S Raman, Carrie R McDonald, Nikdokht Farid, Santosh Kesari, Donna Hansel, Ahmed Shabaik, Anders M Dale, David S Karow
Restriction spectrum imaging (RSI) is a novel diffusion-weighted MRI technique that uses the mathematically distinct behavior of water diffusion in separable microscopic tissue compartments to highlight key aspects of the tissue microarchitecture with high conspicuity. RSI can be acquired in less than 5 min on modern scanners using a surface coil. Multiple field gradients and high b-values in combination with postprocessing techniques allow the simultaneous resolution of length-scale and geometric information, as well as compartmental and nuclear volume fraction filtering...
August 16, 2016: Journal of Magnetic Resonance Imaging: JMRI
Christoph Juchem, S Umesh Rudrapatna, Terence W Nixon, Robin A de Graaf
Gradient-echo echo-planar imaging (EPI) is the primary method of choice in functional MRI and other methods relying on fast MRI to image brain activation and connectivity. However, the high susceptibility of EPI towards B0 magnetic field inhomogeneity poses serious challenges. Conventional magnetic field shimming with low-order spherical harmonic (SH) functions is capable of compensating shallow field distortions, but performs poorly for global brain shimming or on specific areas with strong susceptibility-induced B0 distortions such as the prefrontal cortex (PFC)...
January 15, 2015: NeuroImage
Markus Weiger, Mingming Wu, Moritz C Wurnig, David Kenkel, Wolfgang Jungraithmayr, Andreas Boss, Klaas P Pruessmann
Pulmonary MRI is challenging because of the low proton density and rapid transverse relaxation in the lung associated with microscopic magnetic field inhomogeneities caused by tissue-air interfaces. Therefore, low signal is obtained in gradient and spin echo proton images. Alternatively, non-proton MRI using hyperpolarized gases or radial techniques with ultrashort or zero TE have been proposed to image the lung. Also with the latter approach, the general challenge remains to provide full coverage of the lung at sufficient spatial resolution, signal-to-noise ratio (SNR) and image quality within a reasonable scan time...
September 2014: NMR in Biomedicine
Elmar Laistler, Marie Poirier-Quinot, Simon A Lambert, Rose-Marie Dubuisson, Olivier M Girard, Ewald Moser, Luc Darrasse, Jean-Christophe Ginefri
PURPOSE: To demonstrate the feasibility of a highly sensitive superconducting surface coil for microscopic MRI of the human skin in vivo in a clinical 1.5 Tesla (T) scanner. MATERIALS AND METHODS: A 12.4-mm high-temperature superconducting coil was used at 1.5T for phantom and in vivo skin imaging. Images were inspected to identify fine anatomical skin structures. Signal-to-noise ratio (SNR) improvement by the high-temperature superconducting (HTS) coil, as compared to a commercial MR microscopy coil was quantified from phantom imaging; the gain over a geometrically identical coil made from copper (cooled or not) was theoretically deduced...
February 2015: Journal of Magnetic Resonance Imaging: JMRI
Matthias Alexander Zingg, Shila Pazahr, Fabian Morsbach, Andreas Gutzeit, Walter Wiesner, Bruno Lutz, Beat Knechtle, Thomas Rosemann, Peter Matthias Mundinger, Christoph Alexander Rüst
BACKGROUND: Osteoarthritis is an increasing burden in an ageing population. Sports, especially when leading to an overstress of joints, is under suspicion to provoke or at least accelerate the genesis of osteoarthritis. We present the radiologic findings of a 49-years old ultra-endurance athlete with 35 years of training and competing, whose joints of the lower limbs were examined using three different types of magnetic resonance imaging, including a microscopic magnetic resonance imaging coil...
2013: BMC Musculoskeletal Disorders
S Bianchi, C Martinoli, X Demondion
The diagnosis of disorders of the peripheral nerves (PN) has traditionally been based on clinical and electrophysiological data since nerve tissue cannot be visualized on standard radiographs. More recently, however, nerve structures have been evaluated with magnetic resonance imaging (MRI) and ultrasound (US). The former modality is expensive and not available in all institutions. There are also some contraindications to its use, and the assessment of long nerves can be time-consuming since different coils must be used...
June 2007: Journal of Ultrasound
Jun Zhang Tian, Xiao Fen Ma, Gui Hua Jiang, Jin Fang, Wen Feng Zhan
PURPOSE: Orbital haemangiopericytoma (HPC) is a rare tumor with great histological variability and unpredictable clinical and biological behavior. The precise cell type origin is uncertain. METHOD: A case report is provided. RESULTS: A 24-year-old male patient visited an ophthalmologist because of proptosis, strabismus, and movement limitation of the right eye one year ago. These symptoms worsened rapidly. Histopathology, MRI methods and microscopy coil were applied to study the features of HPC...
December 2012: Eye Science
Helmar Waiczies, Jason M Millward, Stefano Lepore, Carmen Infante-Duarte, Andreas Pohlmann, Thoralf Niendorf, Sonia Waiczies
A comprehensive view of brain inflammation during the pathogenesis of autoimmune encephalomyelitis can be achieved with the aid of high resolution non-invasive imaging techniques such as microscopic magnetic resonance imaging (μMRI). In this study we demonstrate the benefits of cryogenically-cooled RF coils to produce μMRI in vivo, with sufficient detail to reveal brain pathology in the experimental autoimmune encephalomyelitis (EAE) model. We could visualize inflammatory infiltrates in detail within various regions of the brain, already at an early phase of EAE...
2012: PloS One
Ozan Karatağ, Gülden Yenice Karatağ, Hüseyin Özkurt, Hülya Kurtul Değirmenci, Ömer Avlanmış, Muzaffer Başak, Adil Baykan
PURPOSE: This study evaluated the accuracy of phased-array magnetic resonance imaging (MRI) for preoperative local tumor staging in primary rectal cancer and emphasized the importance of the preoperative differentiation of T2 tumors from T3 tumors so the appropriate treatment can be applied. MATERIALS AND METHODS: Twenty-four patients with primary rectal cancer were examined preoperatively using 1.5 T MRI with a phased-array coil. Multiplanar T2-weighted images were obtained...
January 2012: Diagnostic and Interventional Radiology: Official Journal of the Turkish Society of Radiology
Andrea Bartoli, Marc Kotowski, Vitor Mendes Pereira, Karl Schaller
BACKGROUND AND IMPORTANCE: We describe an unusual presentation of a ruptured aneurysm of the posterior communicating artery with an acute intracranial hematoma between the dural layers associated with an acute spinal epidural hematoma descending to L1. CLINICAL PRESENTATION: A 35-year-old woman presented 3 hours after ictus with a postcoital headache, neck stiffness, and bilateral abducens cranial nerve palsy. No other neurological deficits were present. Clinically, she had a subarachnoid hemorrhage World Federation of Neurosurgical Societies grade 1...
October 2011: Neurosurgery
Nicholas W Halpern-Manners, Jeffrey L Paulsen, Vikram S Bajaj, Alexander Pines
Many NMR and MRI methods probe fluid dynamics within macro- and mesoporous materials, but with few exceptions, they report on its macroscopically averaged properties. MRI methods are generally unable to localize microscopic features of flow within macroscopic samples because the fraction of the enclosing detector volume occupied by these features is so small. We have recently overcome this problem using remotely detected MRI velocimetry, a technique in which spatial, chemical, and velocity information about elements of the flow is encoded with a conventional NMR coil and detected sensitively at the sample outflow by a volume-matched microdetector...
April 28, 2011: Journal of Physical Chemistry. A
Hyun-joo Kim, Sang Hoon Lee, Chang Ho Kang, Jeong Ah Ryu, Myung Jin Shin, Kyung-Ja Cho, Woo Shin Cho
OBJECTIVE: We wanted to compare the two-dimensional (2D) fast spin echo (FSE) techniques and the three-dimensional (3D) fast field echo techniques for the evaluation of the chondromalacia patella using a microscopy coil. MATERIALS AND METHODS: Twenty five patients who underwent total knee arthroplasty were included in this study. Preoperative MRI evaluation of the patella was performed using a microscopy coil (47 mm). The proton density-weighted fast spin echo images (PD), the fat-suppressed PD images (FS-PD), the intermediate weighted-fat suppressed fast spin echo images (iw-FS-FSE), the 3D balanced-fast field echo images (B-FFE), the 3D water selective cartilage scan (WATS-c) and the 3D water selective fluid scan (WATS-f) were obtained on a 1...
January 2011: Korean Journal of Radiology: Official Journal of the Korean Radiological Society
Vikram S Bajaj, Jeffrey Paulsen, Elad Harel, Alexander Pines
Magnetic resonance imaging (MRI) can elucidate the interior structure of an optically opaque object in unparalleled detail but is ultimately limited by the need to enclose the object within a detection coil; acquiring the image with increasingly smaller pixels reduces the sensitivity, because each pixel occupies a proportionately smaller fraction of the detector's volume. We developed a technique that overcomes this limitation by means of remotely detected MRI. Images of fluids flowing in channel assemblies are encoded into the phase and intensity of the constituent molecules' nuclear magnetic resonance signals and then decoded by a volume-matched detector after the fluids flow out of the sample...
November 19, 2010: Science
Jeffrey Paulsen, Vikram S Bajaj, Alexander Pines
NMR and MRI can yield detailed chemical and dynamic information about flow at microscopic resolutions, but suffer from low signal to noise relative to alternative techniques for flow measurements. In porous media and microfluidic devices, this sensitivity problem is further exacerbated by magnetic susceptibility broadening and low coil filling factor. Fortunately, remote detection can mitigate these issues by physically separating signal detection from the other steps of the experiment. The technique requires, however, that any measured interactions be encoded in indirectly sampled dimensions, leading to experiments of high dimensionality and correspondingly long acquisition times...
August 2010: Journal of Magnetic Resonance
Razvan Ciocan, Robert E Lenkinski, Jonathan Bernstein, Mirela Bancu, Robert Marquis, Alex Ivanishev, Fotini Kourtelidis, Aya Matsui, Jeffrey Borenstein, John V Frangioni
Presently, signal generation in MRI depends on the concentration and relaxivity of protons or other MR-active nuclei, and contrast depends on local differences in signal. In this proof-of-principle study, we explore the use of nonchemical, solid-state devices for generating detectable signal and/or contrast in vitro and in vivo. We introduce the concept of microresonant devices (MRDs), which are micron-sized resonators fabricated using microelectromechanical systems (MEMS) technology. Fifteen-micrometer (15-microm)-thick, coil MRDs were designed to resonate at the 3T Larmor frequency of protons (127...
April 2009: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Ru-Jun Li, Yi Diao, Qiang Huang, Jun-Kang Shen, Qing Lan
BACKGROUND & OBJECTIVE: In previous reports, orthotopic transplantation models of glioma were produced by injecting cell suspension into the brain of mice, which is complex, time-consuming, and nearly impossible to prepare in a large scale within a short period. This study was to establish human glioma orthotopic transplantation model in nude mice by transplanting tumor tissue in the brain, and investigate magnetic resonance imaging (MRI) of the transplanted tumors. METHODS: Human glioma cells were injected subcutaneously into nude mice to form human glioma...
September 2007: Ai Zheng, Aizheng, Chinese Journal of Cancer
Yoshihide Kanemaki, Yasuyuki Kurihara, Kyoko Okamoto, Yasuo Nakajima, Mamoru Fukuda, Ichiro Maeda, Futoshi Akiyama
PURPOSE: The aim of this retrospective study was to determine and correlate contrast-enhanced areas and multiple internal dark dots and lines on high-resolution magnetic resonance imaging (HR-MRI) with findings in surgical specimens of ductal carcinoma in situ (DCIS) and to evaluate the ability of HR-MRI to detect DCIS lesions and clarify HR-MRI features characteristic of DCIS. MATERIALS AND METHODS: This study retrospectively reviewed 11 patients diagnosed with DCIS who had undergone HR-MRI...
January 2007: Radiation Medicine
M D Keller, G J Galloway, C C Pollitt
REASONS FOR PERFORMING STUDY: Obtaining magnetic resonance images of the inner hoof wall tissue at the microscopic level would enable early accurate diagnosis of laminitis and therefore more effective therapy. OBJECTIVES: To optimise magnetic resonance imaging (MRI) parameters in order to obtain the highest possible resolution of the structures beneath the equine hoof wall. METHODS: Magnetic resonance microscopy (MRM) was performed in front feet from 6 cadaver horses using T2-weighted fast spin echo (FSE-T2), and T1-weighted gradient echo (GRE-T1) sequences...
September 2006: Equine Veterinary Journal
Lu-Ning Wang, Ming-Wei Zhu, Ya-Qing Feng, Jian-Hua Wang
We report clinical, neuroradiologic features, and neuropathologic findings of a 76-year-old man with coexistent Pick's disease and progressive supranuclear palsy. The patient presented with loss of recent memory, abnormal behavior and change in personality at the age of 60. The symptoms were progressive. Three years later, repetitive or compulsive behavior became prominent. About 9 years after onset, he had difficulty moving and became bedridden because of a fracture of his left leg. His condition gradually deteriorated and he developed mutism and became vegetative...
June 2006: Neuropathology: Official Journal of the Japanese Society of Neuropathology
Misa Sumi, Marc Van Cauteren, Takashi Nakamura
OBJECTIVE: We evaluated the diagnostic criteria of high-resolution MRI in differentiating benign and malignant cervical nodes that were palpable and superficial in the neck. SUBJECTS AND METHODS: We performed MR microimaging on 24 histologically proven metastatic nodes, 14 histologically proven lymphomas, and 35 histologically or clinically proven benign nodes in the necks of 26 patients. The lymph nodes were imaged with T1-weighted spin-echo, fat-suppressed T2-weighted turbo spin-echo, and spin-echo diffusion-weighted echo-planar sequences using a 47-mm microscopy coil...
March 2006: AJR. American Journal of Roentgenology
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