Read by QxMD icon Read

Diffusion imaging

Lin Cheng, Matthew D Blackledge, David J Collins, Matthew R Orton, Neil P Jerome, Thorsten Feiweier, Mihaela Rata, Veronica Morgan, Nina Tunariu, Martin O Leach, Dow-Mu Koh
PURPOSE: To introduce T2-adjusted computed DWI (T2-cDWI), a method that provides synthetic images at arbitrary b-values and echo times (TEs) that improve tissue contrast by removing or increasing T2 contrast in diffusion-weighted images. MATERIALS AND METHODS: In addition to the standard DWI acquisition protocol T2-weighted echo-planar images at multiple (≥2) echo times were acquired. This allows voxelwise estimation of apparent diffusion coefficient (ADC) and T2 values, permitting synthetic images to be generated at any chosen b-value and echo time...
October 1, 2016: Computers in Biology and Medicine
Bertram J Wilm, Christoph Barmet, Simon Gross, Lars Kasper, S Johanna Vannesjo, Max Haeberlin, Benjamin E Dietrich, David O Brunner, Thomas Schmid, Klaas P Pruessmann
PURPOSE: The purpose of this work was to improve the quality of single-shot spiral MRI and demonstrate its application for diffusion-weighted imaging. METHODS: Image formation is based on an expanded encoding model that accounts for dynamic magnetic fields up to third order in space, nonuniform static B0 , and coil sensitivity encoding. The encoding model is determined by B0 mapping, sensitivity mapping, and concurrent field monitoring. Reconstruction is performed by iterative inversion of the expanded signal equations...
October 21, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Daniel I Glazer, Elmira Hassanzadeh, Andriy Fedorov, Olutayo I Olubiyi, Shayna S Goldberger, Tobias Penzkofer, Trevor A Flood, Paul Masry, Robert V Mulkern, Michelle S Hirsch, Clare M Tempany, Fiona M Fennessy
OBJECTIVE: To determine if tumor cell density and percentage of Gleason pattern within an outlined volumetric tumor region of interest (TROI) on whole-mount pathology (WMP) correlate with apparent diffusion coefficient (ADC) values on corresponding TROIs outlined on pre-operative MRI. METHODS: Men with biopsy-proven prostate adenocarcinoma undergoing multiparametric MRI (mpMRI) prior to prostatectomy were consented to this prospective study. WMP and mpMRI images were viewed using 3D Slicer and each TROI from WMP was contoured on the high b-value ADC maps (b0, 1400)...
October 22, 2016: Abdominal Radiology
Mir B Alikhan, Garrison Pease, William Watkin, Raymon Grogan, Thomas Krausz, Tatjana Antic
Epithelioid sarcoma (ES) is a malignant mesenchymal neoplasm with some morphologic or immunophenotypic evidence of epithelial differentiation. The "classical" subtype occurs in younger patients, often in distal extremities as compared to the "proximal" type. Tumors of the proximal type primarily arising in solid organs are rare with only few case reports in the literature. We report two cases of primary ES in the kidney of a 27-year-old female and the adrenal gland of a 73-year-old male. Clinical exam and imaging, including computer tomography and positron emission tomography did not reveal tumor elsewhere in both cases...
October 18, 2016: Human Pathology
Mira M Sachdeva, Frederick A Jakobiec, Anna M Stagner, Athanasios Papakostas, Dean Eliott
PURPOSE: Large relaxing retinectomies have become increasingly used in the repair of retinal detachment related to proliferative vitreoretinopathy (PVR). Retinectomies expose the retinal pigment epithelium (RPE) to the vitreous cavity; the direct effects of silicone oil on the RPE are only beginning to be understood. DESIGN: Retrospective case series. PARTICIPANTS: Twelve patients noted to develop pigmented epiretinal deposits at regularly scheduled follow-up visits after repair of complex retinal detachments using silicone oil tamponade and retinectomy...
October 18, 2016: Ophthalmology
You-Na Lee, Koichi Okumura, Tatsuya Iwata, Kazuhiro Takahashi, Toshiaki Hattori, Makoto Ishida, Kazuaki Sawada
A bio-image sensor using a patterned apyrase-immobilized membrane was developed to visualize the activities of adenosine triphosphate (ATP) and H(+) ion in real-time. An enzymatic membrane patterning technique was suggested to immobilize apyrase on a specific sensing area of a charge coupled device (CCD)-type image sensor. It was able to observe the spatiotemporal information of ATP and H(+) ion. The smallest size of a patterned membrane is 250×250µm(2). The fabrication parameters of the patterned membrane, such as its thickness and the intensity of the incident light used for photolithography, were optimized experimentally...
December 1, 2016: Talanta
A Argente-García, N Jornet-Martínez, R Herráez-Hernández, P Campíns-Falcó
A solid sensor obtained by embedding 1,2-naphthoquinone-4-sulfonate (NQS) into polydimethylsiloxane/tetraethylortosilicate/silicon dioxide nanoparticles composite has been developed to identify and determine amphetamine (AMP), methamphetamine (MAMP), 3,4-methylenedioxymetamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA). The analytes are derivatized inside the composite for 10 min to create a colored product which can be then quantified by measuring the diffuse reflectance or the color intensity after processing the digitalized image...
November 2, 2016: Analytica Chimica Acta
Xinbo Gao, Wenbin Huang, Wei Wang, Minwen Zhou, Jiawei Wang, Shaolin Du, Shida Chen, Xiulan Zhang
OBJECTIVE: To characterize and compare the topographic profile of choroid in eyes after acute primary angle-closure (APAC) and in normal controls. DESIGN, SETTING, AND PARTICIPANTS: A prospective observational study was conducted. Forty-four consecutive patients who had experienced unilateral APAC that was resolved by treatment were recruited. Seventy age- and sex-matched normal individuals were recruited as controls. METHODS: Enhanced depth imaging-optical coherence tomography was used to measure choroidal thickness (CT) in 9 diffuse locations of macular region...
October 2016: Canadian Journal of Ophthalmology. Journal Canadien D'ophtalmologie
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
Swarupa Kancherla, William J Kohler, Yolandi van der Merwe, Kevin C Chan
Visual function has been shown to deteriorate prior to the onset of retinopathy in some diabetic patients and experimental animal models. This suggests the involvement of the brain's visual system in the early stages of diabetes. In this study, we tested this hypothesis by examining the integrity of the visual pathway in a diabetic rat model using in vivo multi-modal magnetic resonance imaging (MRI). Ten-week-old Sprague-Dawley rats were divided into an experimental diabetic group by intraperitoneal injection of 65 mg/kg streptozotocin in 0...
2016: PloS One
Richard Bergholz, Mirjam Rossel, Jan Schroeter, Ralf M Dutescu, Daniel J Salchow
BACKGROUND/PURPOSE: Toxic maculopathy is a rare but severe complication of chloroquine intake. Although the phenotype of established maculopathy was analyzed in detail, few data exist on the ophthalmologic findings in the early stage. METHODS: The authors present 4 female patients with unequivocal signs of chloroquine maculopathy (bilateral [peri-]central scotoma in the visual fields, structural alterations of the macula in the optical coherence tomography) but normal or atypical findings as to fundus autofluorescence imaging...
October 20, 2016: Retinal Cases & Brief Reports
Satoshi Habuchi, Takuya Yamamoto, Yasuyuki Tezuka
We demonstrate a method for the synthesis of cyclic polymers and a protocol for characterizing their diffusive motion in a melt state at the single molecule level. An electrostatic self-assembly and covalent fixation (ESA-CF) process is used for the synthesis of the cyclic poly(tetrahydrofuran) (poly(THF)). The diffusive motion of individual cyclic polymer chains in a melt state is visualized using single molecule fluorescence imaging by incorporating a fluorophore unit in the cyclic chains. The diffusive motion of the chains is quantitatively characterized by means of a combination of mean-squared displacement (MSD) analysis and a cumulative distribution function (CDF) analysis...
September 26, 2016: Journal of Visualized Experiments: JoVE
Prashanthi Vemuri, David S Knopman, Clifford R Jack, Emily S Lundt, Stephen D Weigand, Samantha M Zuk, Kaely B Thostenson, Robert I Reid, Kejal Kantarci, Yelena Slinin, Kamakshi Lakshminarayan, Cynthia S Davey, Anne Murray
BACKGROUND: Chronic kidney disease (CKD) studies have reported variable prevalence of brain pathologies, in part due to low inclusion of participants with moderate to severe CKD. OBJECTIVE: To measure the association between kidney function biomarkers and brain MRI findings in CKD. METHODS: In the BRINK (BRain IN Kidney Disease) study, MRI was used to measure gray matter volumes, cerebrovascular pathologies (white matter hyperintensity (WMH), infarctions, microhemorrhages), and microstructural changes using diffusion tensor imaging (DTI)...
October 19, 2016: Journal of Alzheimer's Disease: JAD
Francesco Giganti, Alessandro Ambrosi, Maria Chiara Petrone, Carla Canevari, Damiano Chiari, Annalaura Salerno, Paolo Giorgio Arcidiacono, Roberto Nicoletti, Luca Albarello, Elena Mazza, Francesca Gallivanone, Luigi Gianolli, Elena Orsenigo, Antonio Esposito, Carlo Staudacher, Alessandro Del Maschio, Francesco De Cobelli
OBJECTIVES: To compare the diagnostic performance of Magnetic Resonance (MR) and diffusion-weighted imaging (DWI), Multidetector Computed Tomography (MDCT), Endoscopic Ultrasonography (EUS) and (18)F-FDG (Fluorodeoxyglucose) Positron Emission Tomography - Computed Tomography (PET-CT) in the preoperative loco-regional staging of oesophageal cancer. METHODS: Eighteen patients with oesophageal or Siewert I tumour (9 directly treated with surgery and 9 addressed to chemo/radiotherapy before) underwent 1...
October 21, 2016: British Journal of Radiology
Gil Henkin, Daniel Berard, Francis Stabile, Marjan Shayegan, Jason S Leith, Sabrina R Leslie
We present a dynamically adjustable nanofluidic platform for formatting the conformations of and visualizing the interaction kinetics between biomolecules in solution, offering new time resolution and control of the reaction processes. This platform extends Convex Lens-induced Confinement (CLiC), a technique for imaging molecules under confinement, by introducing a system for in-situ modification of the chemical environment; this system uses a deep microchannel to diffusively exchange reagents within the nanoscale imaging region, whose height is fixed by a nanopost array...
October 21, 2016: Analytical Chemistry
Maxime Barat, Audrey Fohlen, Christophe Cassinotto, Anne Sophie Jannot, Raphael Dautry, Jean-Pierre Pelage, Mourad Boudiaf, Marc Pocard, Clarisse Eveno, Bachir Taouli, Philippe Soyer, Anthony Dohan
PURPOSE: To assess whether apparent diffusion coefficient (ADC) values at 1 and 3 months after radiofrequency ablation (RFA) may be associated with a favorable response to therapy for hepatocellular carcinoma (HCC) and liver metastases. MATERIALS AND METHODS: Fifty-nine patients with HCC (n = 35) or liver metastases (n = 24) who underwent 1.5T diffusion-weighted magnetic resonance imaging (DWMRI) at 1 and 3 months post-RFA were included. ADC values of patients with local tumor recurrence were compared to those without local recurrence...
October 20, 2016: Journal of Magnetic Resonance Imaging: JMRI
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
Francesca Guidotti, Gioia Piatti, Alessia Marcon, Elena Cassinerio, Marianna Giuditta, Alberto Roghi, Valter Fasano, Dario Consonni, Maria Domenica Cappellini
Although pulmonary function abnormalities in thalassaemia major (TM) were described in 1980, the pathogenetic mechanism is not clear and data are contradictory, probably because of study heterogeneity and the multifactorial nature of the pathogenesis. We retrospectively analysed 73 adult TM patients to evaluate the prevalence of pulmonary dysfunction in adult TM and investigate relationships with iron load. All patients underwent body plethysmography and carbon monoxide diffusion (DLCO) was assessed in 63, in addition to blood tests, echocardiogram and T2* myocardial and liver magnetic resonance imaging...
October 21, 2016: British Journal of Haematology
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
Cameron A Elliott, Vijay Ramaswamy, Francois D Jacob, Tejas Sankar, Vivek Mehta
BACKGROUND: Traumatic brain injury (TBI) is a major cause of infant morbidity and mortality. In these patients, magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) is the test of choice to describe the extent of microstructural injury. CASE PRESENTATION AND DISCUSSION: In this case series, we describe novel acute and chronic MRI findings in four infants (6-19 months) with small, unilateral subdural hematomas in whom the etiology of head injury was suspicious for non-accidental trauma (NAT)...
October 20, 2016: Child's Nervous System: ChNS: Official Journal of the International Society for Pediatric Neurosurgery
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"