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https://www.readbyqxmd.com/read/28549310/segmentation-of-lumen-and-outer-wall-of-abdominal-aortic-aneurysms-from-3d-black-blood-mri-with-a-registration-based-geodesic-active-contour-model
#1
Yan Wang, Florent Seguro, Evan Kao, Yue Zhang, Farshid Faraji, Chengcheng Zhu, Henrik Haraldsson, Michael Hope, David Saloner, Jing Liu
Segmentation of the geometric morphology of abdominal aortic aneurysm is important for interventional planning. However, the segmentation of both the lumen and the outer wall of aneurysm in magnetic resonance (MR) image remains challenging. This study proposes a registration based segmentation methodology for efficiently segmenting MR images of abdominal aortic aneurysms. The proposed methodology first registers the contrast enhanced MR angiography (CE-MRA) and black-blood MR images, and then uses the Hough transform and geometric active contours to extract the vessel lumen by delineating the inner vessel wall directly from the CE-MRA...
May 19, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28548328/epithelioid-trophoblastic-tumor-of-the-uterus-a-case-report-with-radiologic-pathologic-correlation
#2
Ayumi Ohya, Kayoko Higuchi, Hisashi Shimojo, Yasunari Fujinaga, Masumi Kadoya, Shigeki Shiohara
Herein, we report a rare case of an epithelioid trophoblastic tumor of the uterus with radiologic-pathologic correlation in a 56-year-old postmenopausal woman. On T2-weighted magnetic resonance (MR) imaging, the tumor appeared as a hypointense irregular mass compared with the surrounding myometrium of the uterine corpus and encircled the cavity of the lower uterine segment. On dynamic contrast-enhanced MR images, the tumor appeared as a hypovascular mass and an inhomogeneously hyperintense mass in the delayed phase...
May 26, 2017: Journal of Obstetrics and Gynaecology Research
https://www.readbyqxmd.com/read/28547590/perfusion-and-diffusion-mri-signatures-in-histologic-and-genetic-subtypes-of-who-grade-ii-iii-diffuse-gliomas
#3
Kevin Leu, Garrett A Ott, Albert Lai, Phioanh L Nghiemphu, Whitney B Pope, William H Yong, Linda M Liau, Timothy F Cloughesy, Benjamin M Ellingson
The value of perfusion and diffusion-weighted MRI in differentiating histological subtypes according to the 2007 WHO glioma classification scheme (i.e. astrocytoma vs. oligodendroglioma) and genetic subtypes according to the 2016 WHO reclassification (e.g. 1p/19q co-deletion and IDH1 mutation status) in WHO grade II and III diffuse gliomas remains controversial. In the current study, we describe unique perfusion and diffusion MR signatures between histological and genetic glioma subtypes. Sixty-five patients with 2007 histological designations (astrocytomas and oligodendrogliomas), 1p/19q status (+ = intact/- = co-deleted), and IDH1 mutation status (MUT/WT) were included in this study...
May 25, 2017: Journal of Neuro-oncology
https://www.readbyqxmd.com/read/28546249/jugular-anomalies-in-multiple-sclerosis-are-associated-with-increased-collateral-venous-flow
#4
S K Sethi, A M Daugherty, G Gadda, D T Utriainen, J Jiang, N Raz, E M Haacke
BACKGROUND AND PURPOSE: To date, research on extracranial venous collaterals has been focused on structure, with relatively little attention paid to hemodynamics. We addressed this limitation by quantitatively comparing collateral flow in patients with multiple sclerosis and healthy controls by using phase-contrast MR imaging. We hypothesize that patients with MS with structurally anomalous internal jugular veins will have elevated collateral venous flow compared with healthy controls...
May 25, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28544025/phase-imaging-of-axonal-integrity-of-cranial-corticospinal-tract-in-experimental-spinal-cord-injury-at-9-4t
#5
Genxia He, Junchao Qian
It was known that Spinal cord injury (SCI) leads to neuronal cell death, axonal damage and demyelination, and often results in severe functional loss. Noninvasive imaging of axonal integrity may hold great importance in clinic. This study evaluated the role of phase imaging in detection of axonal integrity of cranial corticospinal tract after spinal cord injury. Quantitative MR phase imaging and diffusion tensor imaging were performed on a group of rats prior to and after spinal cord injury at 9.4 T in this study...
May 23, 2017: Microscopy Research and Technique
https://www.readbyqxmd.com/read/28543961/automated-low-contrast-pattern-recognition-algorithm-for-magnetic-resonance-image-quality-assessment
#6
Morgan Ehman, Zhonghao Bao, Scott A Stiving, Mallik Kasam, Dianna Lanners, Teresa Peterson, Renee Jonsgaard, Rickey Carter, Kiaran P McGee
PURPOSE: Low contrast (LC) detectability is a common test criterion for diagnostic radiologic quality control (QC) programs. Automation of this test is desirable in order to reduce human variability and to speed up analysis. However, automation is challenging due to the complexity of the human visual perception system and the ability to create algorithms that mimic this response. This paper describes the development and testing of an automated LC detection algorithm for use in the analysis of magnetic resonance (MR) images of the American College of Radiology (ACR) QC phantom...
May 24, 2017: Medical Physics
https://www.readbyqxmd.com/read/28543071/differentiating-enhancing-multiple-sclerosis-lesions-glioblastoma-and-lymphoma-with-dynamic-texture-parameters-analysis-dtpa-a-feasibility-study
#7
Rajeev K Verma, Roland Wiest, C Locher, Mirjam R Heldner, Phillip Schucht, Andreas Raabe, Jan Gralla, Christian Philipp Kamm, Johannes Slotboom, Frauke Kellner-Weldon
PURPOSE: MR-imaging hallmarks of glioblastoma (GB), cerebral lymphoma (CL), and demyelinating lesions are gadolinium (Gd) uptake due to blood brain barrier disruption. Thus, initial diagnosis may be difficult based on conventional Gd enhanced MRI alone. Here, the added value of a dynamic texture parameter analysis (DTPA) in the differentiation between these three entities is examined. DTPA is an in-house software tool that incorporates the analysis of quantitative texture parameters extracted from dynamic susceptibility contrast enhanced (DSCE) images...
May 19, 2017: Medical Physics
https://www.readbyqxmd.com/read/28542553/quantitative-mri-for-analysis-of-peritumoral-edema-in-malignant-gliomas
#8
Ida Blystad, J B Marcel Warntjes, Örjan Smedby, Peter Lundberg, Elna-Marie Larsson, Anders Tisell
BACKGROUND AND PURPOSE: Damage to the blood-brain barrier with subsequent contrast enhancement is a hallmark of glioblastoma. Non-enhancing tumor invasion into the peritumoral edema is, however, not usually visible on conventional magnetic resonance imaging. New quantitative techniques using relaxometry offer additional information about tissue properties. The aim of this study was to evaluate longitudinal relaxation R1, transverse relaxation R2, and proton density in the peritumoral edema in a group of patients with malignant glioma before surgery to assess whether relaxometry can detect changes not visible on conventional images...
2017: PloS One
https://www.readbyqxmd.com/read/28540825/the-role-of-t1-perfusion-based-classification-in-predicting-the-outcome-of-magnetic-resonance-guided-high-intensity-focused-ultrasound-treatment-of-adenomyosis
#9
Bilgin Keserci, Nguyen Minh Duc
OBJECTIVE: To assess the relationship between magnetic resonance (MR) T1 perfusion-based classification and the outcome of MR-guided high intensity focused ultrasound treatment of adenomyosis, defined as nonperfused volume (NPV) ratio. METHODS: The adenomyosis of 31 women was classified into group A (time-signal intensity [SI] curve of adenomyosis lower than that of the myometrium) and group B (time-SI curve of adenomyosis equal to or higher than that of the myometrium) on the basis of time-SI curves on dynamic contrast enhanced (DCE) MR images acquired at screening...
May 19, 2017: International Journal of Hyperthermia
https://www.readbyqxmd.com/read/28540807/technical-aspects-of-osteoid-osteoma-ablation-in-children-using-mr-guided-high-intensity-focussed-ultrasound
#10
Pavel S Yarmolenko, Avinash Eranki, Ari Partanen, Haydar Celik, AeRang Kim, Matthew Oetgen, Viktoriya Beskin, Domiciano Santos, Janish Patel, Peter C W Kim, Karun Sharma
BACKGROUND: Osteoid osteoma (OO) is a painful bone tumour occurring in children and young adults. Magnetic resonance imaging-guided high intensity focussed ultrasound (MR-HIFU) allows non-invasive treatment without ionising radiation exposure, in contrast to the current standard of care treatment with radiofrequency ablation (RFA). This report describes technical aspects of MR-HIFU ablation in the first 8 paediatric OO patients treated in a safety and feasibility clinical trial (total enrolment of up to 12 patients)...
April 24, 2017: International Journal of Hyperthermia
https://www.readbyqxmd.com/read/28540521/comparative-study-of-fat-suppression-techniques-for-hip-arthroplasty-mr-imaging
#11
Sébastien Molière, Jean-Philippe Dillenseger, Matthieu Ehlinger, Stéphane Kremer, Guillaume Bierry
OBJECTIVES: The goal of this study was to evaluate different fat-suppressed fluid-sensitive sequences in association with different metal artifacts reduction techniques (MARS) to determine which combination allows better fat suppression around metallic hip implants. METHODS: An experimental study using an MRI fat-water phantom quantitatively evaluated contrast shift induced by metallic hip implant for different fat-suppression techniques and MARS. Then a clinical study with patients addressed to MRI unit for painful hip prosthesis compared these techniques in terms of fat suppression quality and diagnosis confidence...
May 24, 2017: Skeletal Radiology
https://www.readbyqxmd.com/read/28540212/infarct-characterization-using-ct
#12
REVIEW
Ludovico La Grutta, Patrizia Toia, Erica Maffei, Filippo Cademartiri, Roberto Lagalla, Massimo Midiri
Myocardial infarction (MI) is a major cause of death and disability worldwide. The incidence is not expected to diminish, despite better prevention, diagnosis and treatment, because of the ageing population in industrialized countries and unhealthy lifestyles in developing countries. Nowadays it is highly requested an imaging tool able to evaluate MI and viability. Technology improvements determined an expansion of clinical indications from coronary plaque evaluation to functional applications (perfusion, ischemia and viability after MI) integrating additional phases and information in the mainstream examination...
April 2017: Cardiovascular Diagnosis and Therapy
https://www.readbyqxmd.com/read/28539559/simultaneous-visualization-of-vessels-and-brain-tumor-with-contrast-enhanced-three-dimensional-phase-contrast-mr-imaging
#13
Yutaka Shigenaga, Masato Sasaki, Takeshi Ishimoto, Keiko Ama
The sequence for concurrently depicting engulfed vessels and a well-enhanced tumor in once-off scanning has never been reported for preoperative magnetic resonance imaging for brain tumor resection. Multimodal fusion techniques have been recently developed, but the risks of misregistration still remain. Here a case is reported where contrast-enhanced three-dimensional phase contrast sequence concurrently depicted an engulfed vessel and metastatic brain tumor in once-off scanning and related technical aspects are discussed...
May 24, 2017: Magnetic Resonance in Medical Sciences: MRMS
https://www.readbyqxmd.com/read/28536087/workflow-sensitivity-of-post-processing-methods-in-renal-dce-mri
#14
Erik Hanson, Eli Eikefjord, Jarle Rørvik, Erling Andersen, Arvid Lundervold, Erlend Hodneland
OBJECTIVE: Estimation of renal filtration using dynamic contrast-enhanced imaging (DCE-MRI) requires a series of analysis steps. The possible number of distinct post-processing chains is large and grows rapidly with increasing number of processing steps or options. In this study we introduce a framework for systematic evaluation of the post-processing chains. The framework is later used to highlight the workflow processing chain sensitivity towards accuracy in estimation of glomerular filtration rate (GFR)...
May 20, 2017: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/28535640/-study-of-diffusion-weighted-imaging-in-combination-with-conventional-mri-signs-for-inflammation-activity-of-chronic-hepatitis-b
#15
H W Ren, H Y Ye, W M An, J H Dong, Y Liu
Objective: To study the correlation between ADC values of diffusion weighted imaging (DWI) and the pathological grading in inflammation activity of chronic hepatitis B, and combined with conventional MRI features to predict the diagnosis effectiveness. Methods: A total of 142 cases of patients with chronic hepatitis B were selected as inflammatory group in 302 Hospital of PLA from January 2014 to December 2015, while 20 cases of healthy subjects without history of liver disease were chosen as control group...
May 23, 2017: Zhonghua Yi Xue za Zhi [Chinese medical journal]
https://www.readbyqxmd.com/read/28535120/differentiation-of-recurrent-glioblastoma-from-delayed-radiation-necrosis-by-using-voxel-based-multiparametric-analysis-of-mr-imaging-data
#16
Ra Gyoung Yoon, Ho Sung Kim, Myeong Ju Koh, Woo Hyun Shim, Seung Chai Jung, Sang Joon Kim, Jeong Hoon Kim
Purpose To assess a volume-weighted voxel-based multiparametric (MP) clustering method as an imaging biomarker to differentiate recurrent glioblastoma from delayed radiation necrosis. Materials and Methods The institutional review board approved this retrospective study and waived the informed consent requirement. Seventy-five patients with pathologic analysis-confirmed recurrent glioblastoma (n = 42) or radiation necrosis (n = 33) who presented with enlarged contrast material-enhanced lesions at magnetic resonance (MR) imaging after they completed concurrent chemotherapy and radiation therapy were enrolled...
May 23, 2017: Radiology
https://www.readbyqxmd.com/read/28534182/imaging-children-suffering-from-lymphoma-an-evaluation-of-different-18-f-fdg-pet-mri-protocols-compared-to-whole-body-dw-mri
#17
Julian Kirchner, Cornelius Deuschl, Bernd Schweiger, Ken Herrmann, Michael Forsting, Christian Buchbender, Gerald Antoch, Lale Umutlu
OBJECTIVES: The objectives of this study were to evaluate and compare the diagnostic potential of different PET/MRI reading protocols, entailing non-enhanced / contrast-enhanced and diffusion-weighted (18)F-FDG PET/MR imaging and whole-body diffusion-weighted MRI for lesion detection and determination of the tumor stage in pediatric lymphoma patients. METHODS: A total of 28 (18)F-FDG PET/MRI datasets were included for analysis of four different reading protocols: (1) PET/MRI utilizing sole unenhanced T2w and T1w imaging, (2) PET/MRI utilizing additional contrast enhanced sequences, (3) PET/MR imaging utilizing unenhanced, contrast enhanced and DW imaging or (4) WB-DW-MRI...
May 22, 2017: European Journal of Nuclear Medicine and Molecular Imaging
https://www.readbyqxmd.com/read/28532491/evaluation-of-an-automated-thresholding-algorithm-for-the-quantification-of-paraspinal-muscle-composition-from-mri-images
#18
Maryse Fortin, Mona Omidyeganeh, Michele Crites Battié, Omair Ahmad, Hassan Rivaz
BACKGROUND: The imaging assessment of paraspinal muscle morphology and fatty infiltration has gained considerable attention in the past decades, with reports suggesting an association between muscle degenerative changes and low back pain (LBP). To date, qualitative and quantitative approaches have been used to assess paraspinal muscle composition. Though highly reliable, manual thresholding techniques are time consuming and not always feasible in a clinical setting. The tedious and rater-dependent nature of such manual thresholding techniques provides the impetus for the development of automated or semi-automated segmentation methods...
May 22, 2017: Biomedical Engineering Online
https://www.readbyqxmd.com/read/28531213/perfusion-mr-imaging-detection-of-carcinoma-arising-from-preexisting-salivary-gland-pleomorphic-adenoma-by-computer-assisted-analysis-of-time-signal-intensity-maps
#19
Ikuo Katayama, Sato Eida, Shuichi Fujita, Yuka Hotokezaka, Misa Sumi, Takashi Nakamura
Tumor perfusion can be evaluated by analyzing the time-signal intensity curve (TIC) after dynamic contrast-enhanced (DCE) MR imaging. Accordingly, TIC profiles are characteristic of some benign and malignant salivary gland tumors. A carcinoma ex pleomorphic adenoma (CXPA) arises from a long-standing pleomorphic adenoma (PA) and has a distinctive prognostic risk depending on the tumor growth potential such as invasion beyond the preexisting capsule. Differentiating CXPA from PA can be very challenging. In this study, we have attempted to discriminate CXPA from PA based on a two-dimensional TIC mapping algorithm...
2017: PloS One
https://www.readbyqxmd.com/read/28530849/allergic-bronchopulmonary-aspergillosis-in-cystic-fibrosis-mr-imaging-of-airway-mucus-contrasts-as-a-tool-for-diagnosis
#20
Gaël Dournes, Patrick Berger, John Refait, Julie Macey, Stephanie Bui, Laurence Delhaes, Michel Montaudon, Olivier Corneloup, Jean-François Chateil, Roger Marthan, Michaël Fayon, François Laurent
Purpose To assess the diagnostic accuracy of mucus contrast characterization by using magnetic resonance (MR) imaging to discriminate allergic bronchopulmonary aspergillosis (ABPA) in cystic fibrosis (CF). Materials and Methods The study was approved by the local Ethics Committee, and all patients or their parents gave written informed consent. One hundred ten consecutive patients with CF were screened between January 2014 and July 2015. All patients underwent a non-contrast material-enhanced MR protocol that included routine T1-weighted and T2-weighted sequences...
May 22, 2017: Radiology
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