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MR image segmentation

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https://www.readbyqxmd.com/read/28338446/the-use-of-hippocampal-volumetric-measurements-to-improve-diagnostic-accuracy-in-pediatric-patients-with-mesial-temporal-sclerosis
#1
Gloria J Guzmán Pérez-Carrillo, Christopher Owen, Katherine E Schwetye, Spencer McFarlane, Ananth K Vellimana, Soe Mar, Michelle M Miller-Thomas, Joshua S Shimony, Matthew D Smyth, Tammie L S Benzinger
OBJECTIVE Many patients with medically intractable epilepsy have mesial temporal sclerosis (MTS), which significantly affects their quality of life. The surgical excision of MTS lesions can result in marked improvement or even complete resolution of the epileptic episodes. Reliable radiological diagnosis of MTS is a clinical challenge. The purpose of this study was to evaluate the utility of volumetric mapping of the hippocampi for the identification of MTS in a case-controlled series of pediatric patients who underwent resection for medically refractory epilepsy, using pathology as a gold standard...
March 24, 2017: Journal of Neurosurgery. Pediatrics
https://www.readbyqxmd.com/read/28336781/quantitative-evaluation-of-two-scatter-correction-techniques-for-18-f-fdg-brain-pet-mr-imaging-in-regard-to-mr-based-attenuation-correction
#2
Jarmo Teuho, Virva Saunavaara, Tuula Tolvanen, Terhi Tuokkola, Antti Karlsson, Jouni Tuisku, Mika Teräs
In positron emission tomography (PET), corrections for photon scatter and attenuation are essential for visual and quantitative consistency. Magnetic resonance attenuation correction (MRAC) is generally conducted by image segmentation and assignment of discrete attenuation coefficients, which offers limited accuracy compared to computed tomography attenuation correction (CTAC). Potential inaccuracies in MRAC may affect scatter correction, as the attenuation image (µ-map) is used in single scatter simulation (SSS) to calculate the scatter estimate...
March 23, 2017: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
https://www.readbyqxmd.com/read/28334490/mr-cholangiography-in-potential-liver-donors-quantitative-and-qualitative-improvement-with-administration-of-an-oral-effervescent-agent
#3
Heon-Ju Kwon, Kyoung Won Kim, Sang Hyun Choi, Jin-Hee Jung, So Yeon Kim, Se-Young Kim, Jeongjin Lee, Dong-Hwan Jung, Tae-Yong Ha, Gi-Won Song, Sung-Gyu Lee
PURPOSE: To determine whether an oral effervescent agent improves magnetic resonance cholangiography (MRC) images, both qualitatively and quantitatively, in potential live liver donors. MATERIALS AND METHODS: This retrospective study was approved by the Institutional Review Board, and informed consent was waived. Seventy potential liver donors underwent 2D MRC before and after administration of an oral effervescent agent. One radiologist measured relative contrast ratio (rC) and relative signal intensity (rS) for right and left intrahepatic ducts (RHD and LHD), and common hepatic duct (CHD)...
March 23, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28330587/comparison-of-semi-automated-and-manual-methods-to-measure-the-volume-of-prostate-cancer-on-magnetic-resonance-imaging
#4
L Marin, M Ezziane, E Comperat, P Mozer, G Cancel-Tassin, J-F Coté, D Racoceanu, F Boudghene, O Lucidarme, O Cussenot, R Renard Penna
PURPOSE: The purpose of this study was to determine the accuracy of manual semi-automated and volumetric measurements to assess prostate cancer volume on multiparametric magnetic resonance imaging (MP-MRI) using whole-mount histopathology for validation. MATERIALS AND METHODS: We evaluated 30 consecutive men (median age, 65.7 years; interquartile range [IQR], 61.5-70.9 years) with a median prostatic specific antigen of 8.5ng/dL (IQR, 5.5-10.5ng/dL), who underwent MP-MRI before radical prostatectomy...
March 15, 2017: Diagnostic and Interventional Imaging
https://www.readbyqxmd.com/read/28323377/accuracy-of-pdff-estimation-by-magnitude-based-and-complex-based-mri-in-children-with-mr-spectroscopy-as-a-reference
#5
William M Haufe, Tanya Wolfson, Catherine A Hooker, Jonathan C Hooker, Yesenia Covarrubias, Alex N Schlein, Gavin Hamilton, Michael S Middleton, Jorge E Angeles, Diego Hernando, Scott B Reeder, Jeffrey B Schwimmer, Claude B Sirlin
PURPOSE: To assess and compare the accuracy of magnitude-based magnetic resonance imaging (MRI-M) and complex-based MRI (MRI-C) for estimating hepatic proton density fat fraction (PDFF) in children, using MR spectroscopy (MRS) as the reference standard. A secondary aim was to assess the agreement between MRI-M and MRI-C. MATERIALS AND METHODS: This was a HIPAA-compliant, retrospective analysis of data collected in children enrolled in prospective, Institutional Review Board (IRB)-approved studies between 2012 and 2014...
March 21, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28315882/comparison-of-total-kidney-volume-quantification-methods-in-autosomal-dominant-polycystic-disease-for-a-comprehensive-disease-assessment
#6
Dario Turco, Marco Busutti, Renzo Mignani, Riccardo Magistroni, Cristiana Corsi
BACKGROUND: In recent times, the scientific community has been showing increasing interest in the treatments aimed at slowing the progression of the autosomal dominant polycystic kidney disease (ADPKD). Therefore, in this paper, we test and evaluate the performance of several available methods for total kidney volume (TKV) computation in ADPKD patients - from echography to MRI - in order to optimize patient classification. METHODS: Two methods based on geometric assumptions (mid-slice [MS], ellipsoid [EL]) and a third one on true contour detection were tested on 40 ADPKD patients at different disease stage using MRI...
March 18, 2017: American Journal of Nephrology
https://www.readbyqxmd.com/read/28314198/automated-segmentation-of-mr-imaging-to-determine-normative-central-nervous-system-cerebrospinal-fluid-volumes-in-healthy-volunteers
#7
J Levi Chazen, Jonathan P Dyke, Robert W Holt, Laura Horky, Rachel A Pauplis, Jacob Y Hesterman, P David Mozley, Ajay Verma
An accurate non-invasive method to determine total body cerebrospinal fluid volume has a number of potential diagnostic and therapeutic applications. Herein we describe a technique for automated segmentation of total body MRI data to determine cranial and spinal CSF volume in 15 healthy adults. These in vivo estimates of CSF volume exceed the standard reported volume of 150mL in human adults and provide normative data for diagnosis of disease states such as hydrocephalus and therapy including pharmacologic dosimetry...
March 2, 2017: Clinical Imaging
https://www.readbyqxmd.com/read/28306547/synthetic-ct-for-mri-based-liver-stereotactic-body-radiotherapy-treatment-planning
#8
Jeremy S Bredfeldt, Lianli Liu, Mary Feng, Yue Cao, James M Balter
A technique for generating MRI-derived synthetic CT volumes (MRCTs) is demonstrated in support of adaptive liver stereotactic body radiation therapy (SBRT). Under IRB approval, 16 subjects with hepatocellular carcinoma were scanned using a single MR pulse sequence (T1 Dixon). Air-containing voxels were identified by intensity thresholding on T1-weighted, water and fat images. The envelope of the anterior vertebral bodies was segmented from the fat image and fuzzy-C-means (FCM) was used to classify each non-air voxel as mid-density, lower-density, bone, or marrow in the abdomen, with only bone and marrow classified within the vertebral body envelope...
March 17, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28302606/trochlear-groove-and-trochlear-cistern-useful-anatomic-landmarks-for-identifying-the-tentorial-segment-of-cranial-nerve-iv-on-mri
#9
P M Bunch, H R Kelly, D A Zander, H D Curtin
BACKGROUND AND PURPOSE: The trochlear groove and trochlear cistern are anatomic landmarks closely associated with the tentorial segment of cranial nerve IV. The purposes of this study were to describe the MR imaging appearances of the trochlear groove and trochlear cistern and to test our hypothesis that knowledge of these anatomic landmarks facilitates identification of cranial nerve IV in routine clinical practice. MATERIALS AND METHODS: For this retrospective study, consecutive MR imaging examinations of the sinuses performed in 25 patients (50 sides) at our institution were reviewed...
March 16, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28302273/there-is-good-agreement-between-mr-enterography-and-bowel-ultrasound-with-regards-to-disease-location-and-activity-in-paediatric-inflammatory-bowel-disease
#10
J L Barber, J Maclachlan, K Planche, M Furman, D Crespi, N Bab, I Beal
AIM: To investigate concordance of bowel ultrasound and magnetic resonance enterography (MRE) in identifying active disease in children with inflammatory bowel disease. MATERIALS AND METHODS: The imaging of children with inflammatory bowel disease who had undergone bowel ultrasound and MRE within 30 days were retrospectively reviewed, from January 2009 to November 2015. Ultrasound was without oral contrast medium; MRI was conducted with patients unsedated with oral contrast medium and gadolinium...
March 14, 2017: Clinical Radiology
https://www.readbyqxmd.com/read/28298033/diffusion-tractography-imaging-guided-frameless-linear-accelerator-stereotactic-radiosurgical-thalamotomy-for-tremor-case-report
#11
Won Kim, Justin Sharim, Stephen Tenn, Tania Kaprealian, Yvette Bordelon, Nzhde Agazaryan, Nader Pouratian
Essential tremor and Parkinson's disease-associated tremor are extremely prevalent within the field of movement disorders. The ventral intermediate (VIM) nucleus of the thalamus has been commonly used as both a neuromodulatory and neuroablative target for the treatment of these forms of tremor. With both deep brain stimulation and Gamma Knife radiosurgery, there is an abundance of literature regarding the surgical planning, targeting, and outcomes of these methodologies. To date, there have been no reports of frameless, linear accelerator (LINAC)-based thalomotomies for tremor...
February 24, 2017: Journal of Neurosurgery
https://www.readbyqxmd.com/read/28291745/iterative-framework-for-the-joint-segmentation-and-ct-synthesis-of-mr-images-application-to-mri-only-radiotherapy-treatment-planning
#12
Ninon Burgos, Filipa Guerreiro, Jamie McClelland, Benoit Presles, Marc Modat, Simeon Nill, David Dearnaley, Nandita deSouza, Uwe Oelfke, Antje-Christin Knopf, Sebastien Ourselin, M Jorge Cardoso
To tackle the problem of MRI-only radiotherapy treatment planning (RTP), we propose a multi-atlas information propagation scheme that jointly segments organs and generates pseudo CT data from structural MR images. As the performance of the method strongly depends on the quality of the atlas database composed of multiple sets of aligned MR, CT and segmented images, we also propose a robust way of registering atlas MR and CT images, which combines structure-guided registration, and CT and MR image synthesis. We first evaluated the proposed framework in terms of segmentation and CT synthesis accuracy on 15 subjects with prostate cancer...
March 14, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28291265/t1-weighted-in-vivo-human-whole-brain-mri-dataset-with-an-ultrahigh-isotropic-resolution-of-250-%C3%AE-m
#13
Falk Lüsebrink, Alessandro Sciarra, Hendrik Mattern, Renat Yakupov, Oliver Speck
We present an ultrahigh resolution in vivo human brain magnetic resonance imaging (MRI) dataset. It consists of T1-weighted whole brain anatomical data acquired at 7 Tesla with a nominal isotropic resolution of 250 μm of a single young healthy Caucasian subject and was recorded using prospective motion correction. The raw data amounts to approximately 1.2 TB and was acquired in eight hours total scan time. The resolution of this dataset is far beyond any previously published in vivo structural whole brain dataset...
March 14, 2017: Scientific Data
https://www.readbyqxmd.com/read/28289991/quantitative-analysis-of-late-gadolinium-enhancement-in-hypertrophic-cardiomyopathy-comparison-of-diagnostic-performance-in-myocardial-fibrosis-between-gadobutrol-and-gadopentetate-dimeglumine
#14
Dongting Liu, Xiaohai Ma, Jiayi Liu, Lei Zhao, Hui Chen, Lei Xu, Zhonghua Sun, Zhanming Fan
The purpose of this study was to compare different semi-automated late gadolinium enhancement (LGE) quantification techniques using gadobutrol and gadopentetate dimeglumine contrast agents with regard to the diagnosis of fibrotic myocardium in patients with hypertrophic cardiomyopathy (HCM). Thirty patients with HCM underwent two cardiac MRI protocols with use of gadobutrol and gadopentetate dimeglumine. Contrast-to-noise ratio (CNR) between LGE area and remote myocardium (CNRremote), between LGE area and left ventricular blood pool (CNRpool), and signal-to-noise ratio (SNR) in LGE were compared...
March 13, 2017: International Journal of Cardiovascular Imaging
https://www.readbyqxmd.com/read/28283726/magnetic-resonance-enterography-has-good-inter-rater-agreement-and-diagnostic-accuracy-for-detecting-inflammation-in-pediatric-crohn-disease
#15
Peter C Church, Mary-Louise C Greer, Ruth Cytter-Kuint, Andrea S Doria, Anne M Griffiths, Dan Turner, Thomas D Walters, Brian M Feldman
BACKGROUND: Magnetic resonance enterography (MRE) is increasingly relied upon for noninvasive assessment of intestinal inflammation in Crohn disease. However very few studies have examined the diagnostic accuracy of individual MRE signs in children. OBJECTIVE: We have created an MR-based multi-item measure of intestinal inflammation in children with Crohn disease - the Pediatric Inflammatory Crohn's MRE Index (PICMI). To inform item selection for this instrument, we explored the inter-rater agreement and diagnostic accuracy of individual MRE signs of inflammation in pediatric Crohn disease and compared our findings with the reference standards of the weighted Pediatric Crohn's Disease Activity Index (wPCDAI) and C-reactive protein (CRP)...
March 10, 2017: Pediatric Radiology
https://www.readbyqxmd.com/read/28283244/left-atrial-mechanics-in-patients-with-acute-stemi-and-secondary-mitral-regurgitation-a-prospective-pilot-cmr-feature-tracking-study
#16
Tomas Lapinskas, Paulius Bučius, Laura Urbonaitė, Agnieta Stabinskaitė, Živilė Valuckienė, Lina Jankauskaitė, Rimantas Benetis, Remigijus Žaliūnas
BACKGROUND AND OBJECTIVE: Left atrium (LA) is an important biomarker of adverse cardiovascular outcomes and cerebrovascular events. This study aimed to evaluate LA myocardial deformation using cardiac magnetic resonance feature tracking (CMR-FT) in patients with acute ST-segment elevation myocardial infarction (STEMI) and secondary mitral regurgitation (MR). Additionally, to assess interobserver and intraobserver variability of the technique. MATERIALS AND METHODS: Twenty patients with STEMI underwent CMR with a 1...
March 1, 2017: Medicina
https://www.readbyqxmd.com/read/28279861/local-gray-level-s-curve-transformation-a-generalized-contrast-enhancement-technique-for-medical-images
#17
Akash Gandhamal, Sanjay Talbar, Suhas Gajre, Ahmad Fadzil M Hani, Dileep Kumar
Most medical images suffer from inadequate contrast and brightness, which leads to blurred or weak edges (low contrast) between adjacent tissues resulting in poor segmentation and errors in classification of tissues. Thus, contrast enhancement to improve visual information is extremely important in the development of computational approaches for obtaining quantitative measurements from medical images. In this research, a contrast enhancement algorithm that applies gray-level S-curve transformation technique locally in medical images obtained from various modalities is investigated...
March 3, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/28278002/quantifying-abdominal-adipose-tissue-and-thigh-muscle-volume-and-hepatic-proton-density-fat-fraction-repeatability-and-accuracy-of-an-mr-imaging-based-semiautomated-analysis-method
#18
Michael S Middleton, William Haufe, Jonathan Hooker, Magnus Borga, Olof Dahlqvist Leinhard, Thobias Romu, Patrik Tunón, Gavin Hamilton, Tanya Wolfson, Anthony Gamst, Rohit Loomba, Claude B Sirlin
Purpose To determine the repeatability and accuracy of a commercially available magnetic resonance (MR) imaging-based, semiautomated method to quantify abdominal adipose tissue and thigh muscle volume and hepatic proton density fat fraction (PDFF). Materials and Methods This prospective study was institutional review board- approved and HIPAA compliant. All subjects provided written informed consent. Inclusion criteria were age of 18 years or older and willingness to participate. The exclusion criterion was contraindication to MR imaging...
March 9, 2017: Radiology
https://www.readbyqxmd.com/read/28277554/morphological-changes-of-anterior-cerebral-artery-aca-in-hydrocephalic-pediatric-patients
#19
Sait Ozturk, Erdogan Ayan, Metin Kaplan
OBJECTIVE: The morphology of anterior cerebral artery (ACA) in patients with hydrocephalus (HCP) was analyzed, and its importance was discussed in maintaining cerebral perfusion. MATERIALS & METHODS: A total of 84 cases in 2 groups between 0 and 3 months, followed-up at Firat Universitesi Hastanesi, Beyin Cerrahisi Klinigi, Elazig, Turkiye due to in 2010-2013, were enrolled. Two groups were created for the study. Group 1; patients with HCP and Group 2; as control group without HCP...
2017: Iranian Journal of Child Neurology
https://www.readbyqxmd.com/read/28271516/can-diffusion-tensor-imaging-and-tractography-represent-cross-sectional-area-of-lumbar-multifidus-in-patients-with-lumbar-spine-disease
#20
Jeehae Oh, Joon-Yong Jung, Young Jin Ko
INTRODUCTION: Cross-sectional area (CSA) is a useful measurement to evaluate the lumbar multifidus, but it cannot reflect morphological characteristics of the entire muscle. Recently, diffusion tensor imaging (DTI) and tractography (DTT) have been used to assess 3-dimensional muscle structures both qualitatively and quantitatively. This study investigated the correlation between CSA and multifidus volume and the clinical utility of DTI and DTT. METHODS: Twenty-eight lumbar multifidi from 14 subjects with lumbar spine disease were analyzed...
March 8, 2017: Muscle & Nerve
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