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https://www.readbyqxmd.com/read/28645214/sodium-fluorescein-facilitates-guided-sampling-of-diagnostic-tumor-tissue-in-nonenhancing-gliomas
#1
Stephen G Bowden, Justin A Neira, Brian J A Gill, Timothy H Ung, Zachary K Englander, George Zanazzi, Peter D Chang, Jorge Samanamud, Jack Grinband, Sameer A Sheth, Guy M McKhann, Michael B Sisti, Peter Canoll, Randy S D'Amico, Jeffrey N Bruce
BACKGROUND: Accurate tissue sampling in nonenhancing (NE) gliomas is a unique surgical challenge due to their intratumoral histological heterogeneity and absence of contrast enhancement as a guide for intraoperative stereotactic guidance. Instead, T2/fluid-attenuated inversion-recovery (FLAIR) hyperintensity on MRI is commonly used as an imaging surrogate for pathological tissue, but sampling from this region can yield nondiagnostic or underdiagnostic brain tissue. Sodium fluorescein is an intraoperative fluorescent dye that has a high predictive value for tumor identification in areas of contrast enhancement and NE in glioblastomas...
June 21, 2017: Neurosurgery
https://www.readbyqxmd.com/read/28644979/intraoperative-fast-ripples-independently-predict-postsurgical-epilepsy-outcome-comparison-with-other-electrocorticographic-phenomena
#2
Shaun A Hussain, Gary W Mathern, Phoebe Hung, Julius Weng, Raman Sankar, Joyce Y Wu
In the surgical management of epilepsy, the resection of cortex exhibiting interictal fast ripples (250-500Hz) on electrocorticography has been linked to postoperative seizure-freedom. Although fast ripples appear to accurately identify the epileptogenic zone-the minimum tissue that must be removed at surgery to achieve seizure-freedom-it has not been established that fast ripples are a superior biomarker in comparison with multimodal presurgical neuroimaging and other electrocorticography abnormalities. Hence, in the prediction of postoperative seizure-freedom, we compared the value of fast ripples with other intraoperative electocorticography abnormalities including focal slowing, paroxysmal fast activity, intermittent spike discharges, continuous epileptiform discharges, focal attenuation, and intraoperative seizures, as well as complete resection of the lesion defined by MRI and other neuroimaging...
June 16, 2017: Epilepsy Research
https://www.readbyqxmd.com/read/28644905/a-realistic-phantom-for-validating-mri-based-synthetic-ct-images-of-the-human-skull
#3
Abraam S Soliman, Levi Burns, Amir Owrangi, Young Lee, William Y Song, Greg Stanisz, Brige P Chugh
PURPOSE: To introduce a new realistic human skull phantom for the validation of synthetic CT images of cortical bone from ultra-short echo-time (UTE) sequences. METHODS AND MATERIALS: A human skull of an adult female was utilized as a realistic representation of skull cortical bone. The skull was stabilized in a special acrylic container and was filled with contrast agents that have T1 and T2 relaxation times similar to human brain. The phantom was MR scanned at 3T with UTE and T2 -weighted sequences, followed by CT...
June 23, 2017: Medical Physics
https://www.readbyqxmd.com/read/28644152/incorporating-hypr-de-noising-within-iterative-pet-reconstruction-hypr-osem
#4
Ju-Chieh Kevin Cheng, Julian C Matthews, Vesna Sossi, Jose Anton-Rodriguez, Andre Salomon, Ronald Boellaard
HighlY constrained back-PRojection (HYPR) is a post-processing de-noising technique originally developed for time-resolved Magnetic Resonance Imaging. It has been recently applied to dynamic imaging for Positron Emission Tomography (PET) and shown promising results. In this work, we have developed an iterative reconstruction algorithm (HYPR-OSEM) which improves the signal-to-noise ratio (SNR) in static imaging (i.e. single frame reconstruction) by incorporating HYPR de-noising directly within the ordered subsets expectation maximization (OSEM) algorithm...
June 23, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28644110/detailed-magnetic-resonance-imaging-features-of-a-case-series-of-primary-gliosarcoma
#5
Luísa Sampaio, Paulo Linhares, José Fonseca
Objective We aimed to characterise the magnetic resonance imaging (MRI) features of a case series of primary gliosarcoma, with the inclusion of diffusion-weighted imaging and perfusion imaging with dynamic susceptibility contrast MRI. Materials and methods We conducted a retrospective study of cases of primary gliosarcoma from the Pathology Department database from January 2006 to December 2014. Clinical and demographic data were obtained. Two neuroradiologists, blinded to diagnosis, assessed tumour location, signal intensity in T1 and T2-weighted images, pattern of enhancement, diffusion-weighted imaging and dynamic susceptibility contrast MRI studies on preoperative MRI...
January 1, 2017: Neuroradiology Journal
https://www.readbyqxmd.com/read/28644065/ventricular-pseudodiverticula-from-intraparenchymal-cerebrospinal-fluid-dissection-secondary-to-high-grade-obstructive-hydrocephalus-in-children-magnetic-resonance-imaging-findings
#6
Sonia F Calloni, Bruno P Soares, Thierry Agm Huisman
We report on a series of three children who presented with a focal cerebrospinal fluid collection within the periventricular white matter of the temporal and occipital lobes in the setting of high-grade obstructive hydrocephalus. Magnetic resonance imaging showed a focal defect within the ventricular wall associated with leakage of cerebrospinal fluid into the adjacent white matter. The white matter tracts appeared primarily displaced. This entity should be referred to as ventricular pseudodiverticulum, not lined by ependymal cells, in contrast to a true ventricular diverticulum in which the cerebrospinal fluid is contained by a focal outpouching of the intact ventricular wall lined by a dilated and prolapsed layer of ependymal cells...
January 1, 2017: Neuroradiology Journal
https://www.readbyqxmd.com/read/28643777/in-situ-targeted-mri-detection-of-helicobacter-pylori-with-stable-magnetic-graphitic-nanocapsules
#7
Yunjie Li, Xiaoxiao Hu, Ding Ding, Yuxiu Zou, Yiting Xu, Xuewei Wang, Yin Zhang, Long Chen, Zhuo Chen, Weihong Tan
Helicobacter pylori infection is implicated in the aetiology of many diseases. Despite numerous studies, a painless, fast and direct method for the in situ detection of H. pylori remains a challenge, mainly due to the strong acidic/enzymatic environment of the gastric mucosa. Herein, we report the use of stable magnetic graphitic nanocapsules (MGNs), for in situ targeted magnetic resonance imaging (MRI) detection of H. pylori. Several layers of graphene as the shell effectively protect the magnetic core from corrosion while retaining the superior contrast effect for MRI in the gastric environment...
June 15, 2017: Nature Communications
https://www.readbyqxmd.com/read/28643695/highly-fluorescent-and-superparamagnetic-nanosystem-for-biomedical-applications
#8
Mariana P Cabrera, Paulo E Cabral Filho, Camila M C M Silva, Rita M Oliveira, Carlos F G C Geraldes, M Margarida C A Castro, Benilde F O Costa, Marta S C Henriques, José A Paixão, Luiz B Carvalho, Beate S Santos, Fernando Hallwass, Adriana Fontes, Giovannia A L Pereira
This work reports on highly fluorescent and superparamagnetic bimodal nanoparticles (BNPs) obtained by a simple and efficient method as probes for fluorescence analysis and/or contrast agents for MRI. These promising BNPs with small dimensions (ca. 17 nm) consist of superparamagnetic iron oxide nanoparticles (SPIONs) covalently bound with CdTe quantum dots (ca. 3 nm). The chemical structure of the magnetic part of BNPs is predominantly magnetite, with minor goethite and maghemite contributions, as shown by Mössbauer spectroscopy, which is compatible with the x-ray diffraction data...
July 14, 2017: Nanotechnology
https://www.readbyqxmd.com/read/28643603/stroke-like-migraine-attacks-after-radiation-therapy-syndrome-case-report-and-review-of-the-literature
#9
Achint K Singh, Bundhit Tantiwongkosi, Anna-Marieta Moise, Wilson B Altmeyer
A 26-year-old female presented with vision loss accompanied by migraine-like headaches. A contrast-enhanced magnetic resonance imaging of the brain was performed which revealed findings suggestive of stroke-like migraine attacks after radiation therapy (SMART) syndrome. SMART syndrome is a delayed complication of brain radiation characterized by neurologic symptoms including migraine-like headaches, seizures, and hemispheric impairment. The purpose of this article is to make the readers aware of this rare complication of brain irradiation...
January 1, 2017: Neuroradiology Journal
https://www.readbyqxmd.com/read/28643545/application-of-intravoxel-incoherent-motion-ivim-magnetic-resonance-imaging-in-the-evaluation-of-primitive-brain-tumours
#10
A Catanese, F Malacario, L Cirillo, F Toni, C Zenesini, D Casolino, A Bacci, R Agati
Intravoxel incoherent motion is a potential non-invasive diagnostic tool in brain tumours, without any clear guidelines for its evaluation yet. In our study, we compare intravoxel incoherent motion with dynamic susceptibility contrast magnetic resonance imaging in the quantification of tumour tissue blood perfusion in 28 patients affected by brain tumours, highlighting the issues encountered during the acquisition set-up and post-processing steps. Intravoxel incoherent motion is a new imaging tool and an alternative technique to dynamic susceptibility contrast-magnetic resonance imaging which is of considerable interest at present...
January 1, 2017: Neuroradiology Journal
https://www.readbyqxmd.com/read/28643383/multiecho-pseudo-golden-angle-stack-of-stars-thermometry-with-high-spatial-and-temporal-resolution-using-k-space-weighted-image-contrast
#11
Bryant T Svedin, Allison Payne, Bradley D Bolster, Dennis L Parker
PURPOSE: Implement and evaluate a 3D MRI method to measure temperature changes with high spatial and temporal resolution and large field of view. METHODS: A multiecho pseudo-golden angle stack-of-stars (SOS) sequence with k-space weighted image contrast (KWIC) reconstruction was implemented to simultaneously measure multiple quantities, including temperature, initial signal magnitude M(0), transverse relaxation time ( T2*), and water/fat images. Respiration artifacts were corrected using self-navigation...
June 22, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28643359/an-open-8-channel-parallel-transmission-coil-for-static-and-dynamic-7t-mri-of-the-knee-and-ankle-joints-at-multiple-postures
#12
Jin Jin, Ewald Weber, Aurelien Destruel, Kieran O'Brien, Bassem Henin, Craig Engstrom, Stuart Crozier
PURPOSE: We present the initial in vivo imaging results of an open architecture eight-channel parallel transmission (pTx) transceive radiofrequency (RF) coil array that was designed and constructed for static and dynamic 7T MRI of the knee and ankle joints. METHODS: The pTx coil has a U-shaped dual-row configuration (200 mm overall length longitudinally) that allows static and dynamic imaging of the knee and ankle joints at various postures and during active movements...
June 22, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28643295/fat-suppression-techniques-for-breast-mri-dixon-versus-spectral-fat-saturation-for-3d-t1-weighted-at-3%C3%A2-t
#13
Anastasia Kalovidouri, Natacha Firmenich, Benedicte M A Delattre, Marlise Picarra, Christoph D Becker, Xavier Montet, Diomidis Botsikas
OBJECTIVE: To compare two fat suppression techniques used for 3D T1-weighted sequence in breast MRI (magnetic resonance imaging), namely Dixon versus spectral fat saturation (fat sat). MATERIALS AND METHODS: All breast MRI examinations performed in a Philips 3 T unit between March 2013 and October 2015 including either a Dixon or a fat sat sequence were retrospectively analyzed. The examinations were subjectively evaluated by two independent experienced readers in a scale of 5 for overall quality of fat suppression, homogeneity of fat suppression, definition of anatomic structures and focal lesions, diagnostic confidence for axillary and internal mammary regions and the presence of artifacts, 1 corresponding to excellent and 5 to non-diagnostic quality...
June 22, 2017: La Radiologia Medica
https://www.readbyqxmd.com/read/28643038/prevalence-of-cerebral-cavernous-malformations-associated-with-developmental-venous-anomalies-increases-with-age
#14
Waleed Brinjikji, Ali El-Rida El-Masri, John T Wald, Kelly D Flemming, Giuseppe Lanzino
BACKGROUND AND PURPOSE: To test the hypothesis that the prevalence of cerebral cavernous malformation (CCM) associated with developmental venous anomalies (DVAs) increases with age, we studied the age-related prevalence of DVA-associated CCM among patients with DVAs. MATERIALS AND METHODS: Patients with DVAs on contrast-enhanced MRI exams performed over a 2-year period were included in this study. A single neuroradiologist reviewed all imaging exams for the presence of CCMs...
June 22, 2017: Child's Nervous System: ChNS: Official Journal of the International Society for Pediatric Neurosurgery
https://www.readbyqxmd.com/read/28642994/cardiovascular-magnetic-resonance-imaging-to-assess-myocardial-fibrosis-in-valvular-heart-disease
#15
Tomaz Podlesnikar, Victoria Delgado, Jeroen J Bax
The left ventricular (LV) remodeling process associated with significant valvular heart disease (VHD) is characterized by an increase of myocardial interstitial space with deposition of collagen and loss of myofibers. These changes occur before LV systolic function deteriorates or the patient develops symptoms. Cardiovascular magnetic resonance (CMR) permits assessment of reactive fibrosis, with the use of T1 mapping techniques, and replacement fibrosis, with the use of late gadolinium contrast enhancement...
June 22, 2017: International Journal of Cardiovascular Imaging
https://www.readbyqxmd.com/read/28642699/cerebral-blood-flow-and-amyloid-%C3%AE-interact-to-affect-memory-performance-in-cognitively-normal-older-adults
#16
Katherine J Bangen, Alexandra L Clark, Emily C Edmonds, Nicole D Evangelista, Madeleine L Werhane, Kelsey R Thomas, Lyzette E Locano, My Tran, Zvinka Z Zlatar, Daniel A Nation, Mark W Bondi, Lisa Delano-Wood
Cerebral blood flow (CBF) alterations and amyloid-β (Aβ) accumulation have been independently linked to cognitive deficits in older adults at risk for dementia. Less is known about how CBF and Aβ may interact to affect cognition in cognitively normal older adults. Therefore, we examined potential statistical interactions between CBF and Aβ status in regions typically affected in Alzheimer's disease (AD) within a sample of older adults from the Alzheimer's Disease Neuroimaging Initiative (ADNI) study. Sixty-two cognitively normal participants (mean age = 72 years) underwent neuroimaging and memory testing...
2017: Frontiers in Aging Neuroscience
https://www.readbyqxmd.com/read/28642288/ferumoxytol-enhanced-magnetic-resonance-imaging-assessing-inflammation-after-myocardial-infarction
#17
Colin G Stirrat, Shirjel R Alam, Thomas J MacGillivray, Calum D Gray, Marc R Dweck, Jennifer Raftis, William Sa Jenkins, William A Wallace, Renzo Pessotto, Kelvin Hh Lim, Saeed Mirsadraee, Peter A Henriksen, Scott Ik Semple, David E Newby
OBJECTIVES: Macrophages play a central role in the cellular inflammatory response to myocardial infarction (MI) and predict subsequent clinical outcomes. We aimed to assess temporal changes in cellular inflammation and tissue oedema in patients with acute MI using ultrasmallsuperparamagnetic particles of iron oxide (USPIO)-enhanced MRI. METHODS: Thirty-one patients were recruited following acute MI and followed up for 3 months with repeated T2 and USPIO-enhanced T2*-mapping MRI...
June 22, 2017: Heart: Official Journal of the British Cardiac Society
https://www.readbyqxmd.com/read/28642265/the-initial-area-under-the-curve-derived-from-dynamic-contrast-enhanced-mri-improves-prognosis-prediction-in-glioblastoma-with-unmethylated-mgmt-promoter
#18
Y S Choi, S S Ahn, H-J Lee, J H Chang, S-G Kang, E H Kim, S H Kim, S-K Lee
BACKGROUND AND PURPOSE: Although perfusion and permeability MR parameters have known to have prognostic value, they have reproducibility issues. Our aim was to evaluate whether the initial area under the time-to-signal intensity curve (IAUC) derived from dynamic contrast-enhanced MR imaging can improve prognosis prediction in patients with glioblastoma with known MGMT status. MATERIALS AND METHODS: We retrospectively examined 88 patients with glioblastoma who underwent preoperative dynamic contrast-enhanced MR imaging...
June 22, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28641819/dynamic-contrast-enhanced-mr-imaging-of-carotid-vasa-vasorum-in-relation-to-coronary-and-cerebrovascular-events
#19
Juan Wang, Huijun Chen, Jie Sun, Daniel S Hippe, Huawei Zhang, Shengyuan Yu, Jianming Cai, Leixing Xie, Bao Cui, Chun Yuan, Xihai Zhao, Weimin Yuan, Hongbin Liu
BACKGROUND AND AIMS: Dynamic contrast-enhanced MR imaging (DCE-MRI) provides a noninvasive approach to the functional status of carotid adventitial vasa vasorum. Contrast extravasation rate, or K(trans), derived from kinetic modeling of adventitial enhancement, has been correlated with plaque neovascularization and inflammation. This study sought to clarify the clinical implications of K(trans) by evaluating its relationship with documented cardiovascular events (CVE). METHODS: Seventy patients with carotid plaque at clinical ultrasound examination were recruited and imaged with a previously-described bright-blood DCE-MRI protocol (spatial resolution: 0...
June 3, 2017: Atherosclerosis
https://www.readbyqxmd.com/read/28641813/sensors-and-bioassays-powered-by-upconverting-materials
#20
REVIEW
Diego Mendez-Gonzalez, Enrique Lopez-Cabarcos, Jorge Rubio-Retama, Marco Laurenti
In recent years, considerable efforts have been done to better understand the peculiar emission properties of upconverting materials due to their widespread applications in different and important technological fields such as upconversion-based photoactivated cancer therapies, photoactivated drug-delivery, magnetic resonance imaging contrast agents, bioimaging. However, one of the most promising applications of upconverting materials concerns the field of sensing, due to their unique emission properties. In fact, the minimal autofluorescence, blinking, photo-bleaching, and high photostability makes them an excellent alternative to organic dyes or quantum dots...
June 10, 2017: Advances in Colloid and Interface Science
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