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MR image segmentation

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https://www.readbyqxmd.com/read/28220583/morphometric-analysis-of-prostate-zonal-anatomy-using-magnetic-resonance-imaging-mri-the-impact-on-age-related-changes-in-japanese-and-american-populations
#1
Toru Matsugasumi, Atsuko Fujihara, So Ushijima, Motohiro Kanazawa, Yasuhiro Yamada, Takumi Shiraishi, Fumiya Hongo, Kazumi Kamoi, Koji Okihara, Andre Luis de Castro Abreu, Masakatsu Oishi, Toshitaka Shin, Suzanne Palmer, Inderbir S Gill, Osamu Ukimura
OBJECTIVES: Magnetic resonance imaging (MRI) can be used to reliably evaluate prostate zonal anatomy. Objectives of this study was to evaluate the impact of morphometric MRI analysis of the prostate zonal anatomy on aging, prostatic hypertrophy, and lower urinary tract symptoms in patients from Japan and the USA. SUBJECTS AND METHODS: A retrospective analysis of 307 men, including Japanese (n=156) and American (n=151) patients, who consecutively underwent 3-Tesla MRI and International Prostate Symptom Score (IPSS) due to elevated PSA...
February 20, 2017: BJU International
https://www.readbyqxmd.com/read/28220266/interpretation-of-cardiac-wall-motion-from-cine-mri-combined-with-parametric-imaging-based-on-the-hilbert-transform
#2
Narjes Benameur, Enrico Gianluca Caiani, Younes Arous, Nejmeddine Ben Abdallah, Tarek Kraiem
OBJECT: The aim of this study was to test and validate the clinical impact of parametric amplitude images obtained using the Hilbert transform on the regional interpretation of cardiac wall motion abnormalities from cine-MR images by non-expert radiologists compared with expert consensus. MATERIALS AND METHODS: Cine-MRI short-axis images obtained in 20 patients (10 with myocardial infarction, 5 with myocarditis and 5 with normal function) were processed to compute a parametric amplitude image for each using the Hilbert transform...
February 20, 2017: Magma
https://www.readbyqxmd.com/read/28217825/preoperative-prediction-of-muscular-invasiveness-of-bladder-cancer-with-radiomic-features-on-conventional-mri-and-its-high-order-derivative-maps
#3
Xiaopan Xu, Yang Liu, Xi Zhang, Qiang Tian, Yuxia Wu, Guopeng Zhang, Jiang Meng, Zengyue Yang, Hongbing Lu
PURPOSE: To determine radiomic features which are capable of reflecting muscular invasiveness of bladder cancer (BC) and propose a non-invasive strategy for the differentiation of muscular invasiveness preoperatively. METHODS: Sixty-eight patients with clinicopathologically confirmed BC were included in this retrospective study. A total of 118 cancerous volumes of interest (VOI) were segmented from patients' T2 weighted MR images (T2WI), including 34 non-muscle invasive bladder carcinomas (NMIBCs, stage <T2) and 84 muscle invasive ones (MIBCs, stage ≥T2)...
February 20, 2017: Abdominal Radiology
https://www.readbyqxmd.com/read/28216111/anatomical-regurgitant-orifice-detection-and-quantification-from-3-d-echocardiographic-images
#4
Miguel Sotaquirá, Mauro Pepi, Gloria Tamborini, Enrico G Caiani
The vena contracta and effective regurgitant orifice area (EROA) are currently used for the clinical assessment of mitral regurgitation (MR) from 2-D color Doppler imaging. In addition to being highly user dependent and having low repeatability, these methods do not represent accurately the anatomic regurgitant orifice (ARO), which affects the adequate assessment of MR patients. We propose a novel method for semi-automatic detection and quantitative assessment of the 3-D ARO shape from 3-D transesophageal echocardiographic images...
February 16, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28207388/segmentation-of-pathological-structures-by-landmark-assisted-deformable-models
#5
Bulat Ibragimov, Robert Korez, Bostjan Likar, Franjo Pernus, Lei Xing, Tomaz Vrtovec
Computerized segmentation of pathological structures in medical images is challenging, as, in addition to unclear image boundaries, image artifacts and traces of surgical activities, the shape of pathological structures may be very different from the shape of normal structures. Even if a sufficient number of pathological training samples are collected, statistical shape modeling cannot always capture shape features of pathological samples as they may be suppressed by shape features of a considerably larger number of healthy samples...
February 13, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28205307/segmentation-of-organs-at-risks-in-head-and-neck-ct-images-using-convolutional-neural-networks
#6
Bulat Ibragimov, Lei Xing
PURPOSE: Accurate segmentation of organs-at-risks (OARs) is the key step for efficient planning of radiation therapy for head and neck (HaN) cancer treatment. In the work, we proposed the first deep learning-based algorithm, for segmentation of OARs in HaN CT images, and compared its performance against state-of-the-art automated segmentation algorithms, commercial software, and interobserver variability. METHODS: Convolutional neural networks (CNNs)-a concept from the field of deep learning-were used to study consistent intensity patterns of OARs from training CT images and to segment the OAR in a previously unseen test CT image...
February 2017: Medical Physics
https://www.readbyqxmd.com/read/28203419/diagnosis-of-mitral-valve-cleft-using-real-time-3-dimensional-echocardiography
#7
Xinchun Yuan, Aiyun Zhou, Li Chen, Cheng Zhang, Yan Zhang, Pan Xu
BACKGROUND: Mitral valve cleft (MVC) is the most common cause of congenital mitral insufficiency, and MVC may occur alone or in association with other congenital heart lesions. Direct suture and valvuloplasty are the major and effective treatments for mitral regurgitation (MR) caused by MVC. Therefore, it is important to determine the location and magnitude of the pathological damage due to MVC when selecting a surgical procedure for treatment. This study explored the application value of transthoracic real-time 3-dimensional (3D) echocardiography (RT-3DE) in the diagnosis of MVC...
January 2017: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/28192461/canine-neuroanatomy-development-of-a-3d-reconstruction-and-interactive-application-for-undergraduate-veterinary-education
#8
Hazel Raffan, Julien Guevar, Matthieu Poyade, Paul M Rea
Current methods used to communicate and present the complex arrangement of vasculature related to the brain and spinal cord is limited in undergraduate veterinary neuroanatomy training. Traditionally it is taught with 2-dimensional (2D) diagrams, photographs and medical imaging scans which show a fixed viewpoint. 2D representations of 3-dimensional (3D) objects however lead to loss of spatial information, which can present problems when translating this to the patient. Computer-assisted learning packages with interactive 3D anatomical models have become established in medical training, yet equivalent resources are scarce in veterinary education...
2017: PloS One
https://www.readbyqxmd.com/read/28191031/level-set-based-hippocampus-segmentation-in-mr-images-with-improved-initialization-using-region-growing
#9
Xiaoliang Jiang, Zhaozhong Zhou, Xiaokang Ding, Xiaolei Deng, Ling Zou, Bailin Li
The hippocampus has been known as one of the most important structures referred to as Alzheimer's disease and other neurological disorders. However, segmentation of the hippocampus from MR images is still a challenging task due to its small size, complex shape, low contrast, and discontinuous boundaries. For the accurate and efficient detection of the hippocampus, a new image segmentation method based on adaptive region growing and level set algorithm is proposed. Firstly, adaptive region growing and morphological operations are performed in the target regions and its output is used for the initial contour of level set evolution method...
2017: Computational and Mathematical Methods in Medicine
https://www.readbyqxmd.com/read/28180081/automatic-quantification-of-ischemic-injury-on-diffusion-weighted-mri-of-neonatal-hypoxic-ischemic-encephalopathy
#10
Keelin Murphy, Niek E van der Aa, Simona Negro, Floris Groenendaal, Linda S de Vries, Max A Viergever, Geraldine B Boylan, Manon J N L Benders, Ivana Išgum
A fully automatic method for detection and quantification of ischemic lesions in diffusion-weighted MR images of neonatal hypoxic ischemic encephalopathy (HIE) is presented. Ischemic lesions are manually segmented by two independent observers in 1.5 T data from 20 subjects and an automatic algorithm using a random forest classifier is developed and trained on the annotations of observer 1. The algorithm obtains a median sensitivity and specificity of 0.72 and 0.99 respectively. F1-scores are calculated per subject for algorithm performance (median = 0...
2017: NeuroImage: Clinical
https://www.readbyqxmd.com/read/28177548/7t-guided-super-resolution-of-3t-mri
#11
Khosro Bahrami, Feng Shi, Islem Rekik, Yaozong Gao, Dinggang Shen
PURPOSE: High-resolution MR images can depict rich details of brain anatomical structures and show subtle changes in longitudinal data. 7T MRI scanners can acquire MR images with higher resolution and better tissue contrast than the routine 3T MRI scanners. However, 7T MRI scanners are currently more expensive and less available in clinical and research centers. To this end, we propose a method to generate super-resolution 3T MRI that resembles 7T MRI, which is called as 7T-like MR image in this paper...
February 8, 2017: Medical Physics
https://www.readbyqxmd.com/read/28166261/radiomic-analysis-reveals-dce-mri-features-for-prediction-of-molecular-subtypes-of-breast-cancer
#12
Ming Fan, Hui Li, Shijian Wang, Bin Zheng, Juan Zhang, Lihua Li
The purpose of this study was to investigate the role of features derived from breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and to incorporated clinical information to predict the molecular subtypes of breast cancer. In particular, 60 breast cancers with the following four molecular subtypes were analyzed: luminal A, luminal B, human epidermal growth factor receptor-2 (HER2)-over-expressing and basal-like. The breast region was segmented and the suspicious tumor was depicted on sequentially scanned MR images from each case...
2017: PloS One
https://www.readbyqxmd.com/read/28156213/structural-brain-differences-in-school-age-children-with-and-without-single-suture-craniosynostosis
#13
Kristina Aldridge, Brent R Collett, Erin R Wallace, Craig Birgfeld, Jordan R Austin, Regina Yeh, Madison Feil, Kathleen A Kapp-Simon, Elizabeth H Aylward, Michael L Cunningham, Matthew L Speltz
OBJECTIVE Single-suture craniosynostosis (SSC), the premature fusion of a cranial suture, is characterized by dysmorphology of the craniofacial skeleton. Evidence to suggest that children with SSC are at an elevated risk of mild to moderate developmental delays and neurocognitive deficits is mounting, but the associations among premature suture fusion, neuroanatomy, and neurocognition are unexplained. The goals of this study were to determine 1) whether differences in the brain are present in young children with the 2 most common forms of SSC (sagittal and metopic) several years following surgical correction, and 2) whether the pattern of differences varies by affected suture (sagittal or metopic)...
February 3, 2017: Journal of Neurosurgery. Pediatrics
https://www.readbyqxmd.com/read/28155582/image-derived-input-function-estimation-on-a-tof-enabled-pet-mr-for-cerebral-blood-flow-mapping
#14
Mohammad Mehdi Khalighi, Timothy W Deller, Audrey Peiwen Fan, Praveen K Gulaka, Bin Shen, Prachi Singh, Jun-Hyung Park, Frederick T Chin, Greg Zaharchuk
(15)O-H2O PET imaging is an accurate method to measure cerebral blood flow (CBF) but it requires an arterial input function (AIF). Historically, image-derived AIF estimation suffers from low temporal resolution, spill-in, and spill-over problems. Here, we optimized tracer dose on a time-of-flight PET/MR according to the acquisition-specific noise-equivalent count rate curve. An optimized dose of 850 MBq of (15)O-H2O was determined, which allowed sufficient counts to reconstruct a short time-frame PET angiogram (PETA) during the arterial phase...
January 1, 2017: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/28155029/texture-features-of-periaqueductal-gray-in-the-patients-with-medication-overuse-headache
#15
Zhiye Chen, Xiaoyan Chen, Mengqi Liu, Shuangfeng Liu, Lin Ma, Shengyuan Yu
BACKGROUND: Periaqueductal gray (PAG) is the descending pain modulatory center, and PAG dysfunction had been recognized in migraine. Here we propose to investigate altered PAG texture features (quantitative approach for extracting texture descriptors for images) in the patients with medication-overuse headache (MOH) based on high resolution brain structural image to understand the MOH pathogenesis. METHODS: The brain structural images were obtained from 32 normal controls (NC) and 44 MOH patients on 3...
December 2017: Journal of Headache and Pain
https://www.readbyqxmd.com/read/28152586/novel-flexible-nerve-conduits-made-of-water-based-biodegradable-polyurethane-for-peripheral-nerve-regeneration
#16
Shan-Hui Hsu, Wen-Chi Chang, Chen-Tung Yen
Peripheral nerve conduits were fabricated from biodegradable polyurethane (PU) which was synthesized by a waterborne process. The biodegradable PU was based on poly(ε-caprolactone) diol and polyethylene butylene adipate diol (2:3 molar ratio) as the soft segment. Conduits formed by the freeze-drying process had asymmetric microporous structure. The PU nerve conduits were used to bridge a 10 mm gap in rat sciatic nerve. Nerve regeneration was evaluated by walking track analysis, magnetic resonance imaging (MRI), electrophysiological, and histological analyses...
February 2, 2017: Journal of Biomedical Materials Research. Part A
https://www.readbyqxmd.com/read/28152259/four-dimensional-phase-contrast-vastly-undersampled-isotropic-projection-reconstruction-4d-pc-vipr-mr-evaluation-of-the-renal-arteries-in-transplant-recipients-preliminary-results
#17
Daisuke Motoyama, Yasuo Ishii, Yasuo Takehara, Masataka Sugiyama, Wang Yang, Hatsuko Nasu, Takasuke Ushio, Yuko Hirose, Naoki Ohishi, Tetsuya Wakayama, Hiroyuki Kabasawa, Kevin Johnson, Oliver Wieben, Harumi Sakahara, Seiichiro Ozono
PURPOSE: To assess the performance of four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) at 3.0T in depicting intrarenal arteries compared with computed tomography angiography (CTA), and its correlation with arterial flowmetry in comparison with Doppler ultrasonography (DUS). MATERIALS AND METHODS: In our prospective single-arm study, subjects were 25 patients who underwent renal transplant-related surgery at our hospital between July 2011 and June 2015...
February 2, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28152238/assessment-of-segmental-myocardial-blood-flow-and-myocardial-perfusion-reserve-by-adenosine-stress-myocardial-arterial-spin-labeling-perfusion-imaging
#18
Andrew J Yoon, Hung Phi Do, Steven Cen, Michael W Fong, Farhood Saremi, Mark L Barr, Krishna S Nayak
PURPOSE: To determine the feasibility of measuring increases in myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) on a per-segment basis using arterial spin labeled (ASL) magnetic resonance imaging (MRI) with adenosine vasodilator stress in normal human myocardium. MATERIALS AND METHODS: Myocardial ASL scans at rest and during adenosine infusion were incorporated into a routine 3T MR adenosine-induced vasodilator stress protocol and were performed in 10 healthy human volunteers...
February 2, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28152235/community-delivery-of-semiautomated-fractal-analysis-tool-in-cardiac-mr-for-trabecular-phenotyping
#19
Gabriella Captur, Dina Radenkovic, Chunming Li, Yu Liu, Nay Aung, Filip Zemrak, Catalina Tobon-Gomez, Xuexin Gao, Perry M Elliott, Steffen E Petersen, David A Bluemke, Matthias G Friedrich, James C Moon
PURPOSE: To report the development of easy-to-use magnetic resonance imaging (MRI) fractal tools deployed on platforms accessible to all. The trabeculae of the left ventricle vary in health and disease but their measurement is difficult. Fractal analysis of cardiac MR images can measure trabecular complexity as a fractal dimension (FD). MATERIALS AND METHODS: This Health Insurance Portability and Accountability Act (HIPAA)-compliant study was approved by the local Institutional Review Board...
February 2, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28149968/7t-guided-learning-framework-for-improving-the-segmentation-of-3t-mr-images
#20
Khosro Bahrami, Islem Rekik, Feng Shi, Yaozong Gao, Dinggang Shen
The emerging era of ultra-high-field MRI using 7T MRI scanners dramatically improved sensitivity, image resolution, and tissue contrast when compared to 3T MRI scanners in examining various anatomical structures. The advantages of these high-resolution MR images include higher segmentation accuracy of MRI brain tissues. However, currently, accessibility to 7T MRI scanners remains much more limited than 3T MRI scanners due to technological and economical constraints. Hence, we propose in this work the first learning-based model that improves the segmentation of an input 3T MR image with any conventional segmentation method, through the reconstruction of a higher-quality 7T-like MR image, without actually acquiring an ultra-high-field 7T MRI...
October 2016: Medical Image Computing and Computer-assisted Intervention: MICCAI ..
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