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https://www.readbyqxmd.com/read/28230532/optimization-of-volumetric-breast-density-estimation-in-digital-mammograms
#1
Katharina Holland, Albert Gubern-Merida, Ritse Mann, Nico Karssemeijer
Fibroglandular tissue volume and percent density can be estimated in unprocessed mammograms using a physics-based method, which relies on an internal reference value representing the projection of fat only. However, pixels representing fat only may not be present in dense breasts, causing an underestimation of density measurements. In this work, we investigate alternative approaches for obtaining a tissue reference value to improve density estimations, particularly in dense breasts. Two of three investigated reference values (F1, F2) are percentiles of the pixel value distribution in the breast interior (the contact area of breast and compression paddle)...
February 23, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28230327/fundamentals-of-diffusion-mri-physics
#2
REVIEW
Valerij G Kiselev
Diffusion MRI is commonly considered the "engine" for probing the cellular structure of living biological tissues. The difficulty of this task is threefold. First, in structurally heterogeneous media, diffusion is related to structure in quite a complicated way. The challenge of finding diffusion metrics for a given structure is equivalent to other problems in physics that have been known for over a century. Second, in most cases the MRI signal is related to diffusion in an indirect way dependent on the measurement technique used...
March 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28229430/differences-in-biomarkers-of-cartilage-matrix-turnover-and-their-changes-over-2%C3%A2-years-in-adolescent-and-adult-volleyball-athletes
#3
Heide Boeth, Aoife MacMahon, A Robin Poole, Frank Buttgereit, Patrik Önnerfjord, Pilar Lorenzo, Cecilia Klint, Anna Pramhed, Georg N Duda
BACKGROUND: This study aimed the feasibility to assess longitudinal changes in biomarkers of cartilage turnover and to determine their relationship with patient-rated outcomes over 2 years in volleyball athletes. METHODS: Thirty-seven athletes were studied: 18 adolescents (age 15.9 ± 0.64 years) in a 2-year intensive volleyball training program and 19 adult recreational volleyball players (age 46.5 ± 4.9 years). Blood and serum samples were taken at baseline (BL) and 2-year follow-up (FU)...
December 2017: Journal of Experimental Orthopaedics
https://www.readbyqxmd.com/read/28226714/a-unified-bayesian-based-compensated-magnetic-resonance-imaging
#4
Ameneh Boroomand, Edward Li, Mohammad Javad Shafiee, Masoom A Haider, Farzad Khalvati, Alexander Wong, Ameneh Boroomand, Edward Li, Mohammad Javad Shafiee, Masoom A Haider, Farzad Khalvati, Alexander Wong, Alexander Wong, Mohammad Javad Shafiee, Edward Li, Masoom A Haider, Ameneh Boroomand, Farzad Khalvati
Magnetic resonance (MR) images of higher quality is demanded for helping with more accurate and earlier diagnosis of different diseases. The overall quality of MR images is limited due to the existence of different degradation factors such as (1) MR aberrations due to intrinsic properties of the MR scanner, (2) magnetic field inhomogeneity, and (3) inherent MRI noise. Correcting each MRI degradation factor could be solely useful for the quality enhancement of MR imaging with a limited impact. Here, we propose a unified Bayesian based compensated MR imaging (CMRI) system which jointly corrects for the different aforementioned MR aberrations as well as MR noise and hence generates compensated MR (CMR) images with a higher quality...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226678/hip-segmentation-from-mri-volumes-in-infants-for-ddh-diagnosis-and-treatment-planning
#5
Abhilash Rakkunedeth Hareendranathan, Dornoosh Zonoobi, Myles Mabee, Chad Diederichs, Kumaradevan Punithakumar, Michelle Noga, Jacob L Jaremko, Abhilash Rakkunedeth Hareendranathan, Dornoosh Zonoobi, Myles Mabee, Chad Diederichs, Kumaradevan Punithakumar, Michelle Noga, Jacob L Jaremko, Jacob L Jaremko, Myles Mabee, Dornoosh Zonoobi, Michelle Noga, Chad Diederichs, Kumaradevan Punithakumar, Abhilash Rakkunedeth Hareendranathan
Diagnosis and surgical management of Developmental Dysplasia of the Hip (DDH) relies on physical examination and 2D ultrasound scanning. Magnetic Resonance Imaging (MRI) can be used to complement existing techniques and could be advantageous in treatment planning due to its larger field of view. In this paper we propose a semi-automatic method to segment surface models of the acetabulum from MRI images. The method incorporates clinical knowledge in the form of intensity priors which are integrated into a Random Walker (RW) formulation...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226530/low-rank-magnetic-resonance-fingerprinting
#6
Gal Mazor, Lior Weizman, Assaf Tal, Yonina C Eldar, Gal Mazor, Lior Weizman, Assaf Tal, Yonina C Eldar, Gal Mazor, Assaf Tal, Lior Weizman, Yonina C Eldar
Magnetic Resonance Fingerprinting (MRF) is a relatively new approach that provides quantitative MRI using randomized acquisition. Extraction of physical quantitative tissue values is preformed off-line, based on acquisition with varying parameters and a dictionary generated according to the Bloch equations. MRF uses hundreds of radio frequency (RF) excitation pulses for acquisition, and therefore high under-sampling ratio in the sampling domain (k-space) is required. This under-sampling causes spatial artifacts that hamper the ability to accurately estimate the quantitative tissue values...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28225646/conventional-and-zoomit-dwi-for-evaluation-of-testis-in-patients-with-ipsilateral-varicocele
#7
İsmail Okan Yıldırım, Semih Sağlık, Hüseyin Çelik
OBJECTIVE: The current study aimed to investigate the effects of varicocele on testis parenchyma by using ZOOMit DWI and conventional DWI and to compare both diffusion methods. SUBJECTS AND METHODS: Forty-five patients with unilateral varicocele diagnosed by physical examination and color Doppler ultrasound between July 2015 and December 2015 and 32 healthy volunteers were included in the study. ZOOMit and conventional DWI were performed for all patients with a 3-T MRI scanner...
February 22, 2017: AJR. American Journal of Roentgenology
https://www.readbyqxmd.com/read/28225578/detection-of-volume-alterations-in-hippocampal-subfields-of-rats-under-chronic-unpredictable-mild-stress-using-7t-mri-a-follow-up-study
#8
Yuefeng Li, Xiaolan Zhu, Shenghong Ju, Jinchuan Yan, Dongqing Wang, Yan Zhu, Fengchao Zang
PURPOSE: To determine hippocampal subfields volume loss in depression, which was simulated by a rat chronic unpredictable mild stress (CUMS) model. As different cellular and molecular characteristics in hippocampal subfields, these subfields are regarded as differentially vulnerable to processes associated with stress. MATERIALS AND METHODS: Twenty male Wistar rats were exposed to various stressors until the model was successfully established. The effects of physical exercise on recovery of hippocampal volume in depressed rats were simulated using the wheel running test (WRT)...
February 22, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28222766/increased-cortical-lesion-load-and-intrathecal-inflammation-is-associated-with-oligoclonal-bands-in-multiple-sclerosis-patients-a-combined-csf-and-mri-study
#9
Gabriele Farina, Roberta Magliozzi, Marco Pitteri, Richard Reynolds, Stefania Rossi, Alberto Gajofatto, Maria Donata Benedetti, Francesco Facchiano, Salvatore Monaco, Massimiliano Calabrese
BACKGROUND: Although IgG oligoclonal bands (OCBs) in the cerebrospinal fluid (CSF) are a frequent phenomenon in multiple sclerosis (MS) patients, their relationship with grey matter lesions, intrathecal/meningeal inflammation and clinical evolution has not been clarified yet. The aim of our study was to assess the relationship between the OCBs, the inflammatory/neurodegenerative CSF profile at diagnosis, the cortical lesion load and the clinical evolution after 10 years. METHODS: This is a 10-year observational, cross-sectional study based on a combined MRI, cognitive and CSF profiling of the examined patients...
February 21, 2017: Journal of Neuroinflammation
https://www.readbyqxmd.com/read/28221303/a-case-of-asymptomatic-inclusion-body-myositis
#10
Rey Bello, Tulio Bertorini, Kartheek Ganta, William Mays
OBJECTIVES: To present a case of asymptomatic inclusion body myositis. METHODS: The authors report a case of a 67-year-old man who presented with idiopathic hyperCKemia. Physical examination including a complete neurological evaluation was unremarkable. Systemic causes of hyperCKemia, including medication side effects, metabolic and endocrine disorders, and connective tissue disorders, were ruled out with various indicated tests. RESULTS: Two and a half years after initial consultation, the patient reported left knee pain...
March 2017: Journal of Clinical Neuromuscular Disease
https://www.readbyqxmd.com/read/28218772/diagnosis-and-management-of-abdominal-wall-endometriosis-a-systematic-review-and-clinical-recommendations
#11
Noah B Rindos, Suketu Mansuria
Importance: Abdominal wall endometriosis (AWE) is a rare but easily treated cause of pain in women, especially those who have undergone cesarean deliveries. Objective: This article reviews the diagnosis and management of AWE, a condition that generally develops after surgery but may arise spontaneously. We present a systematic review of the existing literature on AWE, as well as our clinical recommendations for medical and surgical management. Evidence Acquisition: We searched PubMed and other databases using the search criteria "abdominal wall endometriosis," "abdominal wall endometriomas," and "abdominal wall mass...
February 2017: Obstetrical & Gynecological Survey
https://www.readbyqxmd.com/read/28216208/a-rare-case-of-pediatric-lumbar-spinal-ependymoma-mimicking-meningitis
#12
Ezeali Mike Ekuma, Kiyoshi Ito, Akihiro Chiba, Yosuke Hara, Kohei Kanaya, Tetsuyoshi Horiuchi, Samuel Ohaegbulam, Kazuhiro Hongo
Spontaneous acute subarachnoid hemorrhage (SAH) from lumbar ependymoma in children is rare. We report a case of a14-year-old boy who developed sudden radicular low back pain while playing baseball. He was initially managed conservatively in a local hospital for suspected lumbar disc herniation, but later developed meningeal symptoms and fever before being referred to our hospital. There he underwent a diagnostic lumbar puncture in the emergency room; his cerebrospinal fluid suggested an SAH. Physical examination showed meningeal signs and cauda equina features...
February 12, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28215457/synchronous-ipsilateral-cavernous-malformations-of-the-trochlear-nerve
#13
Christopher S Graffeo, William R Copeland, Perkins Mukunyadzi, Ali F Krisht
BACKGROUND: Cranial nerve cavernous malformations (CM) are rare benign congenital vascular anomalies, with approximately 44 preceding cases in the literature. We report the fifth case of trochlear CM, as well as the first instance of two discrete CM occurring simultaneously along the same cranial nerve. METHODS: Case report. RESULTS: A fifty-seven year-old man presented with several years of diplopia; physical examination identified a complete left trochlear nerve paralysis...
February 16, 2017: Journal of Clinical Neuroscience: Official Journal of the Neurosurgical Society of Australasia
https://www.readbyqxmd.com/read/28214544/can-functional-magnetic-resonance-imaging-studies-help-with-the-optimization-of-health-messaging-for-lifestyle-behavior-change-a-systematic-review
#14
REVIEW
Maxine E Whelan, Paul S Morgan, Lauren B Sherar, Mark W Orme, Dale W Esliger
Unhealthy behaviors, including smoking, poor nutrition, excessive alcohol consumption, physical inactivity and sedentary lifestyles, are global risk factors for non-communicable diseases and premature death. Functional magnetic resonance imaging (fMRI) offers a unique approach to optimize health messages by examining how the brain responds to information relating to health. Our aim was to systematically review fMRI studies that have investigated variations in brain activation in response to health messages relating to (i) smoking; (ii) alcohol consumption; (iii) physical activity; (iv) diet; and (v) sedentary behavior...
February 15, 2017: Preventive Medicine
https://www.readbyqxmd.com/read/28214496/new-diagnostic-modalities-in-the-evaluation-of-lymphedema
#15
REVIEW
Thomas F O'Donnell, John C Rasmussen, Eva M Sevick-Muraca
OBJECTIVE: Currently, lymphedema (LED) is typically diagnosed clinically on the basis of a patient's history and characteristic physical findings. Whereas the diagnosis of LED is sometimes confirmed by lymphoscintigraphy (LSG), the technique is limited in both its ability to identify disease and to guide therapy. Recent advancements provide opportunities for new imaging techniques not only to assist in the diagnosis of LED, based on anatomic changes, but also to assess contractile function and to guide therapeutic intervention...
March 2017: Journal of Vascular Surgery. Venous and Lymphatic Disorders
https://www.readbyqxmd.com/read/28214465/acute-and-chronic-lateral-ankle-instability-diagnosis-management-and-new-concepts
#16
Rachel Shakked, Steven Sheskier
Lateral ankle instability is a common entity that can result in degenerative arthritis if left untreated. Acute ligament injuries should primarily be treated nonoperatively with a course of physical therapy and functional bracing. Chronic ankle instability is defined as mechanical or functional and can be diagnosed using a combination of history, physical examination, stress radiographs, and magnetic resonance imaging. After failure of nonoperative treatment, surgical treatment with anatomic ligament repair and inferior extensor retinaculum augmentation has the best clinical outcomes...
January 2017: Bulletin of the Hospital for Joint Diseases
https://www.readbyqxmd.com/read/28214369/diagnostic-accuracy-of-history-physical-exam-laboratory-tests-and-point-of-care-ultrasound-for-pediatric-acute-appendicitis-in-the-emergency-department-a-systematic-review-and-meta-analysis
#17
Roshanak Benabbas, Mark Hanna, Jay Shah, Richard Sinert
BACKGROUND: Acute appendicitis (AA) is the most common surgical emergency in children. Accurate and timely diagnosis is crucial but challenging due to atypical presentations and the inherent difficulty of obtaining a reliable history and physical examination in younger children. OBJECTIVES: To determine the utility of history, physical exam, laboratory tests, Pediatric Appendicitis Score (PAS) and Emergency Department-Point-of-Care Ultrasound (ED-POCUS) in the diagnosis of AA in ED pediatric patients...
February 18, 2017: Academic Emergency Medicine: Official Journal of the Society for Academic Emergency Medicine
https://www.readbyqxmd.com/read/28213111/childhood-maltreatment-is-associated-with-alteration-in-global-network-fiber-tract-architecture-independent-of-history-of-depression-and-anxiety
#18
Kyoko Ohashi, Carl M Anderson, Elizabeth A Bolger, Alaptagin Khan, Cynthia E McGreenery, Martin H Teicher
Childhood maltreatment is a major risk factor for psychopathology. It is also associated with alterations in the network architecture of the brain, which we hypothesized may play a significant role in the development of psychopathology. In this study, we analyzed the global network architecture of physically healthy unmedicated 18-25 year old subjects (n=262) using diffusion tensor imaging (DTI) MRI and tractography. Anatomical networks were constructed from fiber streams interconnecting 90 cortical or subcortical regions for subjects with no-to-low (n=122) versus moderate-to-high (n=140) exposure to maltreatment...
February 16, 2017: NeuroImage
https://www.readbyqxmd.com/read/28212385/the-effect-of-tumour-size-on-drug-transport-and-uptake-in-3-d-tumour-models-reconstructed-from-magnetic-resonance-images
#19
Wenbo Zhan, Wladyslaw Gedroyc, Xiao Yun Xu
Drug transport and its uptake by tumour cells are strongly dependent on tumour properties, which vary in different types of solid tumours. By simulating the key physical and biochemical processes, a numerical study has been carried out to investigate the transport of anti-cancer drugs in 3-D tumour models of different sizes. The therapeutic efficacy for each tumour is evaluated by using a pharmacodynamics model based on the predicted intracellular drug concentration. Simulation results demonstrate that interstitial fluid pressure and interstitial fluid loss vary non-linearly with tumour size...
2017: PloS One
https://www.readbyqxmd.com/read/28211647/clinical-characteristics-predicting-abnormal-brain-magnetic-resonance-image-findings-in-hypoxic-ischemic-encephalopathy-infants
#20
Sook K Yum, Cheong-Jun Moon, Young-Ah Youn, In K Sung
BACKGROUND: The aim of this study was to elucidate the specific clinical characteristics associated with abnormal brain magnetic resonance image(MRI) findings in hypoxic ischemic encephalopathy(HIE) infants in order to discern how to predict poorer outcomes more accurately. METHODS: A retrospective data analysis of HIE infants admitted to the neonatal intensive care unit of a tertiary hospital was performed. Baseline perinatal information and physical and neurological findings were compared in HIE infants according to the presence of abnormal brain MRI findings...
February 17, 2017: Minerva Pediatrica
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