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Mri techniques

Richard Baumgartner, William Cho, Alexandre Coimbra, Christopher Chen, Zaiqi Wang, Arie Struyk, Narayanaswamy Venketasubramanian, May Low, Cindy Gargano, Fuqiang Zhao, Donald Williams, Torsten Reese, Stephanie Seah, Dai Feng, Sonya Apreleva, Esben Petersen, Jeffrey L Evelhoch
PURPOSE: To present the testretest and contrast dose effect results of cerebral blood volume (CBV) functional MRI (fMRI) in healthy human volunteers using ferumoxytol (Feraheme), an ultrasmall-superparamagnetic iron oxide (USPIO) nanoparticle. MATERIALS AND METHODS: This was an open-label, two-period, fixed-sequence study in healthy young volunteers. In eight subjects, using a 3 Tesla field strength system, blood oxygen level dependent (BOLD) and CBV fMRI were acquired in response to a visual black-and-white checkboard stimulation paradigm using an escalating ferumoxytol dose design (250, 350, and 510 mg iron)...
October 24, 2016: Journal of Magnetic Resonance Imaging: JMRI
Ram Iyer, Farzana Nasrin, Elton See, Steven Mathews
Optical coherence tomography (OCT) is a non-invasive imaging technique used to study and understand internal structures of biological tissues such as the anterior chamber of the human eye. An interesting problem is the reconstruction of the shape of the biological tissue from OCT images, that is not only a good fit of the data but also respects the smoothness properties observed in the images. A similar problem arises in Magnetic Resonance Imaging (MRI). We cast the problem as a penalized weighted least squares regression with a penalty on the magnitude of the second derivative (Laplacian) of the surface...
October 19, 2016: IEEE Transactions on Medical Imaging
Franciszek Hennel, Klaas P Pruessmann
PURPOSE: Fourier encoded MRI signal is complex and, therefore, sensitive to uncontrolled phase variations caused, e.g., by object motion. An alternative encoding is proposed which leads to phaseless (positive real) signals and allows the phase fluctuations to be removed by simple magnitude calculation before the Fourier transform. THEORY AND METHODS: Phaseless encoding uses harmonic modulation of the longitudinal magnetization with different frequencies and phases before excitation...
October 23, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
A Gabriella Wernicke, Stefanie P Lazow, Shoshana Taube, Menachem Z Yondorf, Ilhami Kovanlikaya, Dattatreyudu Nori, Paul Christos, John A Boockvar, Susan Pannullo, Philip E Stieg, Theodore H Schwartz
BACKGROUND: Cesium-131 (Cs-131) brachytherapy is used to reduce local recurrence of resected brain metastases. In order to ensure dose homogeneity and reduce risk of radiation necrosis, inter-seed distance and cavity volume must remain stable during delivery. OBJECTIVE: To investigate the efficacy of the "seeds-on-a-string" technique with intracavitary fibrin glue in achieving cavity volume stability. METHODS: We placed intra-operative Cs-131 brachytherapy in 30 cavities post-resection of brain metastases...
March 2016: Oper Neurosurg (Hagerstown)
Aviad Hai, Lili X Cai, Taekwan Lee, Victor S Lelyveld, Alan Jasanoff
Reuptake of neurotransmitters from the brain interstitium shapes chemical signaling processes and is disrupted in several pathologies. Serotonin reuptake in particular is important for mood regulation and is inhibited by first-line drugs for treatment of depression. Here we introduce a molecular-level fMRI technique for micron-scale mapping of serotonin transport in live animals. Intracranial injection of an MRI-detectable serotonin sensor complexed with serotonin, together with serial imaging and compartmental analysis, permits neurotransmitter transport to be quantified as serotonin dissociates from the probe...
October 19, 2016: Neuron
B T Yang, Y Z Wang, F R Sun, J Y Dong
AIM: To investigate the key imaging points in distinguishing ossifying inverted papilloma (IP) from polyps. MATERIALS AND METHODS: The native computed tomography (CT), conventional and enhanced MRI manifestations of 20 ossifying IPs and eight polyps, which were confirmed histopathologically, were retrospectively evaluated by two doctors majoring in head and neck imaging. RESULTS: A significant difference was detected between the two entities for the involved sites (p<0...
October 20, 2016: Clinical Radiology
Bhanu Gogia, Vinodh A Kumar, Lakshmi S Chavali, Leena Ketonen, Jill Hunter, Sujit S Prabhu, Donald Schomer, L Anne Hayman
PURPOSE: Our purpose is to describe the thalamic veins using a novel approach named venous gliography in cases with primary or secondary gliomas of the thalamus. Venous gliography is defined by authors as a method to visualize veins on MRI Brain T1-weighted post contrast scans containing gliomas which have induced regional venous congestion. METHODS: Routine clinical MR Imaging studies were reviewed to assess the presence of thalamic veins in 29 glioma cases. In addition, confocal reconstruction techniques (Anatom-e and Osirix) were used in cases that had thin sections (1...
November 15, 2016: Journal of the Neurological Sciences
Ming-Liang Wang, Wen-Bin Li
Traumatic brain injury (TBI) is closely related to increased incidence of cognitive impairment from the acute phase to chronic phase. At present, the pathological mechanism leading to cognitive impairment after TBI is still not fully understood. We hypothesize that neuron loss, diffuse axonal injury, microbleed, and blood-brain barrier (BBB) disruption altogether contribute to the development of cognitive impairment. Furthermore, the disruption of structural and functional neural network related to the cognitive function might bring about the final step in the occurrence of cognitive impairment after TBI...
November 15, 2016: Journal of the Neurological Sciences
Christian Wybranski, Ilya Adamchic, Friedrich-Wilhelm Röhl, Jens Ricke, Frank Fischbach, Katharina Fischbach
OBJECTIVE: To assess the technical success and duration of magnetic resonance imaging (MRI)-guided freehand direct shoulder arthrography (FDSA) with near real-time imaging implemented in a routine shoulder MRI examination on an open 1.0-T MRI scanner, and to assess the learning curve of residents new to this technique. METHODS: An experienced MRI interventionalist (the expert) performed 125 MRI-guided FDSA procedures, and 75 patients were treated by one of three residents without previous experience in MRI-guided FDSA...
October 22, 2016: Skeletal Radiology
E Mazerand, N Karmani, L Le Fournier, L Laccourreye, H-D Fournier
INTRODUCTION: The image-guided transoral approach (IGTOA) provides a safe exposure to skull base midline lesions and the ventral aspect of the craniovertebral junction (CVJ). The IGTOA has several advantages: the head being placed in the extended position, it decreases the brainstem angulation during surgery; the approach being done through the avascular median pharyngeal raphe, not only lowers the bleeding risk but also provides a direct access to the bony pathology and granulation tissue accessible only via the ventral route...
October 19, 2016: Neuro-Chirurgie
Stephen F Cauley, Kawin Setsompop, Berkin Bilgic, Himanshu Bhat, Borjan Gagoski, Lawrence L Wald
PURPOSE: Fast MRI acquisitions often rely on efficient traversal of k-space and hardware limitations, or other physical effects can cause the k-space trajectory to deviate from a theoretical path in a manner dependent on the image prescription and protocol parameters. Additional measurements or generalized calibrations are typically needed to characterize the discrepancies. We propose an autocalibrated technique to determine these discrepancies. METHODS: A joint optimization is used to estimate the trajectory simultaneously with the parallel imaging reconstruction, without the need for additional measurements...
October 21, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Rosemarie Forstner, Isabelle Thomassin-Naggara, Teresa Margarida Cunha, Karen Kinkel, Gabriele Marselli, Rahel Kubik-Huch, John A Spencer, Andrea Rockall
: An update of the 2010 published ESUR recommendations of MRI of the sonographically indeterminate adnexal mass integrating functional techniques is provided. An algorithmic approach using sagittal T2 and a set of transaxial T1 and T2WI allows categorization of adnexal masses in one of the following three types according to its predominant signal characteristics. T1 'bright' masses due to fat or blood content can be simply and effectively determined using a combination of T1W, T2W and FST1W imaging...
October 21, 2016: European Radiology
Arno Olthoff, Per-Ole Carstens, Shuo Zhang, Eva von Fintel, Tim Friede, Joachim Lotz, Jens Frahm, Jens Schmidt
OBJECTIVE: To assess safety and feasibility of real-time (RT) MRI for evaluation of dysphagia and to compare this technique to standard assessment by flexible endoscopic evaluation of swallowing (FEES) and videofluoroscopy (VF) in a cohort of patients with inclusion body myositis (IBM). METHODS: Using RT-MRI, FEES, and VF, an unselected cohort of 20 patients with IBM was studied as index disease with a uniform dysphagia. Symptoms of IBM and dysphagia were explored by standardized tools including Swallowing-Related Quality of Life Questionnaire (SWAL-QoL), IBM Functional Rating Scale, Patient-Reported Functional Assessment, and Medical Research Council Scale...
October 21, 2016: Neurology
G Bai, C Yang, Y Qiu, M Chen
Open surgery and arthroscopy for the treatment of synovial chondromatosis (SC) of the temporomandibular joint (TMJ) have their advantages and disadvantages. The aim of this study was to report the application and results of the combined use of these two methods in the treatment of SC and the indications for use. A total of 36 patients with magnetic resonance imaging (MRI) confirmation of SC, treated from 2010 to 2015, were included. Patients with tumours in the upper articular cavity and with the extended margin of the medial groove still in-between the medial crest of the condyle and infratemporal space on coronal MRI were selected to undergo open surgery with the assistance of arthroscopy to clear the loose bodies and affected synovium...
October 18, 2016: International Journal of Oral and Maxillofacial Surgery
Filip B J L Stillaert, Casper Sommeling, Salvatore D'Arpa, David Creytens, Koenraad Van Landuyt, Herman Depypere, Rudy Van den Broecke, Stan Monstrey, Phillip N Blondeel, Wayne A Morrison
BACKGROUND: Breast reconstruction involves the use of autologous tissues or implants. Occasionally, microsurgical reconstruction is not an option because of insufficient donor tissues. Fat grafting has become increasingly popular in breast surgery. The challenge with this technique is how to reconstruct a stable and living "scaffold" that resembles a breast. METHODS: Breast reconstruction (n = 7) was performed using intratissular expansion with serial deflation-lipofilling sessions...
September 27, 2016: Journal of Plastic, Reconstructive & Aesthetic Surgery: JPRAS
Edward Johnston, Hayley Pye, Elisenda Bonet-Carne, Eleftheria Panagiotaki, Dominic Patel, Myria Galazi, Susan Heavey, Lina Carmona, Alexander Freeman, Giorgia Trevisan, Clare Allen, Alexander Kirkham, Keith Burling, Nicola Stevens, David Hawkes, Mark Emberton, Caroline Moore, Hashim U Ahmed, David Atkinson, Manuel Rodriguez-Justo, Tony Ng, Daniel Alexander, Hayley Whitaker, Shonit Punwani
BACKGROUND: Whilst multi-parametric magnetic resonance imaging (mp-MRI) has been a significant advance in the diagnosis of prostate cancer, scanning all patients with elevated prostate specific antigen (PSA) levels is considered too costly for widespread National Health Service (NHS) use, as the predictive value of PSA levels for significant disease is poor. Despite the fact that novel blood and urine tests are available which may predict aggressive disease better than PSA, they are not routinely employed due to a lack of clinical validity studies...
October 21, 2016: BMC Cancer
M Aurich, D Albrecht, P Angele, C Becher, S Fickert, J Fritz, P E Müller, P Niemeyer, M Pietschmann, G Spahn, M Walther
Background: Osteochondral lesions (OCL) of the ankle are a common cause of ankle pain. Although the precise pathophysiology has not been fully elucidated, it can be assumed that a variety of factors are responsible, mainly including traumatic events such as ankle sprains. Advances in arthroscopy and imaging techniques, in particular magnetic resonance imaging (MRI), have improved the possibilities for the diagnosis of OCLs of the ankle. Moreover, these technologies aim at developing new classification systems and modern treatment strategies...
October 21, 2016: Zeitschrift Für Orthopädie und Unfallchirurgie
Carolina Rodriguez-Tirado, Takanori Kitamura, Yu Kato, Jeffery W Pollard, John S Condeelis, David Entenberg
Metastasis to secondary sites such as the lung, liver and bone is a traumatic event with a mortality rate of approximately 90% (1). Of these sites, the lung is the most difficult to assess using intravital optical imaging due to its enclosed position within the body, delicate nature and vital role in sustaining proper physiology. While clinical modalities (positron emission tomography (PET), magnetic resonance imaging (MRI) and computed tomography (CT)) are capable of providing noninvasive images of this tissue, they lack the resolution necessary to visualize the earliest seeding events, with a single pixel consisting of nearly a thousand cells...
October 6, 2016: Journal of Visualized Experiments: JoVE
Zhe Zhang, Bing Zhang, Ming Li, Xue Liang, Xiaodong Chen, Renyuan Liu, Xin Zhang, Hua Guo
PURPOSE: To report a diffusion imaging technique insensitive to off-resonance artifacts and motion-induced ghost artifacts using mulitshot Cartesian turbo spin-echo (TSE) acquisition and iterative POCS-based reconstruction of multiplexed sensitivity encoded magnetic resonance imaging (MRI) (POCSMUSE) for phase correction. MATERIALS AND METHODS: Phase insensitive diffusion preparation was used to deal with the violation of the Carr-Purcell-Meiboom-Gill (CPMG) conditions of TSE diffusion-weighted imaging (DWI), followed by a mulitshot Cartesian TSE readout for data acquisition...
October 20, 2016: Journal of Magnetic Resonance Imaging: JMRI
Arash Latifoltojar, Margaret Hall-Craggs, Neil Rabin, Rakesh Popat, Alan Bainbridge, Nikolaos Dikaios, Magdalena Sokolska, Ali Rismani, Shirley D'Sa, Shonit Punwani, Kwee Yong
Cross-sectional imaging techniques are being increasingly used for disease evaluation in patients with multiple myeloma. Whole body magnetic resonance imaging (WB-MRI) scanning is superior to plain radiography in baseline assessment of patients but changes following treatment have not been systematically explored. We carried out paired WB-MRI scans in 21 newly diagnosed patients prior to, and 8-weeks after, starting chemotherapy, and analysed stringently selected focal lesions (FLs) for parametric changes. A total of 323 FLs were evaluated, median 20 per patient...
October 21, 2016: British Journal of Haematology
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