keyword
MENU ▼
Read by QxMD icon Read
search

Diffusion imaging

keyword
https://www.readbyqxmd.com/read/28227857/light-source-depth-estimation-in-porcine-skin-using-spatially-resolved-diffuse-imaging
#1
Kieran A Brennan, Bryan P Ruddy, Poul M F Nielsen, Andrew J Taberner, Kieran A Brennan, Bryan P Ruddy, Poul M F Nielsen, Andrew J Taberner, Bryan P Ruddy, Andrew J Taberner, Poul M F Nielsen, Kieran A Brennan
We present an inexpensive imaging system for measuring the diffuse surface radiance profile produced by a light source within a turbid medium. The diffusion model of light propagation in multiple scattering media is used to estimate the optical properties of a sample and subsequently approximate the depth of an optical source. The system is shown to accurately estimate the relative changes in source depth in a homogeneous phantom. The absolute depth estimate may be improved with a better estimate of the optical parameters...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227854/3d-reconstruction-of-cochlea-using-optical-coherence-tomography
#2
Tuukka Karvonen, Yuki Uranishi, Tatsunori Sakamoto, Yosuke Tona, Kazuya Okamoto, Hiroshi Tamura, Tomohiro Kuroda, Tuukka Karvonen, Yuki Uranishi, Tatsunori Sakamoto, Yosuke Tona, Kazuya Okamoto, Hiroshi Tamura, Tomohiro Kuroda, Yuki Uranishi, Hiroshi Tamura, Tatsunori Sakamoto, Yosuke Tona, Tomohiro Kuroda, Kazuya Okamoto, Tuukka Karvonen
Recently, in vivo visualization of the cochlea and the smaller structures inside of it has been achieved by optical coherence tomography (OCT). This makes it possible to use OCT imaging for diagnosis of diseases such as Meniere's disease through measuring the degree of endolymphatic hydrops. To this end, we present a novel method for 3D segmentation of these cochlear OCT images that is based on superpixels and diffusion maps. The method takes as input grayscale volumetric OCT images and outputs a binary image with the segmented cochlea...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227795/simplified-realistic-human-head-model-for-simulating-tumor-treating-fields-ttfields
#3
Cornelia Wenger, Ze'ev Bomzon, Ricardo Salvador, Peter J Basser, Pedro C Miranda, Cornelia Wenger, Ze'ev Bomzon, Ricardo Salvador, Peter J Basser, Pedro C Miranda, Peter J Basser, Pedro C Miranda, Cornelia Wenger, Ricardo Salvador, Ze'ev Bomzon
Tumor Treating Fields (TTFields) are alternating electric fields in the intermediate frequency range (100-300 kHz) of low-intensity (1-3 V/cm). TTFields are an anti-mitotic treatment against solid tumors, which are approved for Glioblastoma Multiforme (GBM) patients. These electric fields are induced non-invasively by transducer arrays placed directly on the patient's scalp. Cell culture experiments showed that treatment efficacy is dependent on the induced field intensity. In clinical practice, a software called NovoTal(TM) uses head measurements to estimate the optimal array placement to maximize the electric field delivery to the tumor...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227765/distribution-aware-estimation-of-the-minimum-achievable-uncertainty-in-diffusion-tensor-imaging-dti
#4
Andrea Duggento, Marco Giannelli, Carlo Tessa, Simona Lanzafame, Maria Guerrisi, Nicola Toschi, Andrea Duggento, Marco Giannelli, Carlo Tessa, Simona Lanzafame, Maria Guerrisi, Nicola Toschi, Nicola Toschi, Maria Guerrisi, Marco Giannelli, Carlo Tessa, Simona Lanzafame, Andrea Duggento
Diffusion tensor imaging (DTI) provides exquisite sensitivity to structural and microstructural characteristics of brain tissue, and is routinely employed in advanced neuroimaging applications. DTI is commonly performed using intrinsically noisy echo-planar imaging techniques and poses high demands both on scanner performance and on in-scanner subject time, which in turn is directly related to the number of diffusion-weighting direction one requires. While DTI-derived indices such as fractional anisotropy (FA), diffusion tensor trace and anisotropy mode have proven extremely useful in characterizing disease-related aberrations, their estimation is commonly performed using fitting routines that do not properly take into account MRI noise distribution...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227764/enhanced-dual-stage-correlated-diffusion-imaging
#5
Farzad Khalvati, Junjie Zhang, Masoom A Haider, Alexander Wong, Farzad Khalvati, Junjie Zhang, Masoom A Haider, Alexander Wong, Farzad Khalvati, Alexander Wong, Junjie Zhang, Masoom A Haider
Prostate cancer is the most common form of cancer and third leading cause of cancer death in Canadian men. Multi-parametric magnetic resonance imaging (mpMRI) has become a powerful non-invasive diagnostic tool for the detection of prostate cancer. Among mpMRI imaging modalities, diffusion-weighed imaging has shown the most promising results in accurate detection of prostate cancer. Introduced recently, correlated diffusion imaging (CDI) is a new form of diffusion imaging which accounts for the joint correlation of diffusion signal attenuation across multiple gradient pulse strengths and timings to improve the separability of cancerous and healthy tissues...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227763/network-effects-and-pathways-in-deep-brain-stimulation-in-parkinson-s-disease
#6
N Koirala, V Fleischer, O Granert, G Deuschl, M Muthuraman, S Groppa, N Koirala, V Fleischer, O Granert, G Deuschl, M Muthuraman, S Groppa
Deep brain stimulation of subthalamic nucleus (STN-DBS) became a standard therapeutic option in Parkinson's disease (PD), even though the underlying modulated network of STN-DBS is still poorly described. Probabilistic tractography and connectivity analysis as derived from diffusion tensor imaging (DTI) were performed together with modelling of implanted electrode positions and linked postoperative clinical outcome. Fifteen patients with idiopathic PD without dementia were selected for DBS treatment. After pre-processing, probabilistic tractography was run from cortical and subcortical seeds of the hypothesized network to targets represented by the positions of the active DBS contacts...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227762/single-shot-turbo-spin-echo-acquisition-for-in-vivo-cardiac-diffusion-mri
#7
Masoud Edalati, Gregory R Lee, Hui Wang, Michael D Taylor, Yu Y Li, Masoud Edalati, Gregory R Lee, Hui Wang, Michael D Taylor, Yu Y Li, Masoud Edalati, Gregory R Lee, Michael D Taylor, Hui Wang, Yu Y Li
Diffusion MRI offers the ability to noninvasively characterize the microstructure of myocardium tissue and detect disease related pathology in cardiovascular examination. This study investigates the feasibility of in vivo cardiac diffusion MRI under free-breathing condition. A high-speed imaging technique, correlation imaging, is used to enable single-shot turbo spin echo for free-breathing cardiac data acquisition. The obtained in vivo cardiac diffusion-weighted images illustrate robust image quality and minor geometry distortions...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227761/application-of-dti-connectivity-in-lateralization-of-mtle
#8
Mohammad R Nazem-Zadeh, Susan M Bowyer, John E Moran, Esmaeil Davoodi-Bojd, Andrew Zillgitt, Hassan Bagher-Ebadian, Fariborz Mahmoudi, Kost V Elisevich, Hamid Soltanian-Zadeh, Mohammad R Nazem-Zadeh, Susan M Bowyer, John E Moran, Esmaeil Davoodi-Bojd, Andrew Zillgitt, Hassan Bagher-Ebadian, Fariborz Mahmoudi, Kost V Elisevich, Hamid Soltanian-Zadeh, Susan M Bowyer, Hassan Bagher-Ebadian, Esmaeil Davoodi-Bojd, Andrew Zillgitt, Fariborz Mahmoudi, John E Moran, Hamid Soltanian-Zadeh, Kost V Elisevich, Mohammad R Nazem-Zadeh
Diffusion tensor imaging (DTI) is a noninvasive imaging method for measuring the diffusion properties of the underlying white matter tracts through which epileptiform activity is propagated. This study investigates the structural abnormalities quantified by DTI in mesial temporal lobe epilepsy (mTLE). Fiber tracts passing through 54 anatomical sites in 12 adult mTLE patients and 12 age- and gender-matched controls were identified using DTI tractography. DTI nodal degree (ND) and laterality index were then calculated...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227406/multivariate-autoregressive-model-constrained-by-anatomical-connectivity-to-reconstruct-focal-sources
#9
Brahim Belaoucha, Mouloud Kachouane, Theodore Papadopoulo, Brahim Belaoucha, Mouloud Kachouane, Theodore Papadopoulo, Brahim Belaoucha, Theodore Papadopoulo, Mouloud Kachouane
In this paper, we present a framework to reconstruct spatially localized sources from Magnetoencephalography (MEG)/Electroencephalography (EEG) using spatiotemporal constraint. The source dynamics are represented by a Multivariate Autoregressive (MAR) model whose matrix elements are constrained by the anatomical connectivity obtained from diffusion Magnetic Resonance Imaging (dMRI). The framework assumes that the whole brain dynamic follows a constant MAR model in a time window of interest. The source activations and the MAR model parameters are estimated iteratively...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227012/detection-of-mitotic-nuclei-in-breast-histopathology-images-using-localized-acm-and-random-kitchen-sink-based-classifier
#10
K Sabeena Beevi, Madhu S Nair, G R Bindu, K Sabeena Beevi, Madhu S Nair, G R Bindu, G R Bindu, Madhu S Nair
The exact measure of mitotic nuclei is a crucial parameter in breast cancer grading and prognosis. This can be achieved by improving the mitotic detection accuracy by careful design of segmentation and classification techniques. In this paper, segmentation of nuclei from breast histopathology images are carried out by Localized Active Contour Model (LACM) utilizing bio-inspired optimization techniques in the detection stage, in order to handle diffused intensities present along object boundaries. Further, the application of a new optimal machine learning algorithm capable of classifying strong non-linear data such as Random Kitchen Sink (RKS), shows improved classification performance...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226714/a-unified-bayesian-based-compensated-magnetic-resonance-imaging
#11
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/28226713/automatic-workflow-for-narrow-band-laryngeal-video-stitching
#12
Sara Moccia, Veronica Penza, Gabriele Omodeo Vanone, Elena De Momi, Leonardo S Mattos, Sara Moccia, Veronica Penza, Gabriele Omodeo Vanone, Elena De Momi, Leonardo S Mattos, Elena De Momi, Leonardo S Mattos, Gabriele Omodeo Vanone, Veronica Penza, Sara Moccia
In narrow band (NB) laryngeal endoscopy, the clinician usually positions the endoscope near the tissue for a correct inspection of possible vascular pattern alterations, indicative of laryngeal malignancies. The video is usually reviewed many times to refine the diagnosis, resulting in loss of time since the salient frames of the video are mixed with blurred, noisy, and redundant frames caused by the endoscope movements. The aim of this work is to provide to the clinician a unique larynx panorama, obtained through an automatic frame selection strategy to discard non-informative frames...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226709/topology-guided-demons-registration-with-local-rigidity-preservation
#13
Chaojie Zheng, Xiuying Wang, Dagan Feng, Chaojie Zheng, Xiuying Wang, Dagan Feng, Chaojie Zheng, Dagan Feng, Xiuying Wang
Demons has been well recognized for its deformable registration capability. However, it might lead to misregistration due to the large spatial distance between the expected corresponding contents or erroneous diffusion tendency. In this paper, we propose a new energy function with topology energy, distance function and demons energy for deformable registration. The new energy function incorporates topological relationships to guide the correct diffusion and deformation, and contributes to local rigidity preservation...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226697/differences-in-white-matter-microstructure-between-parkinson-s-disease-patients-with-and-without-rem-sleep-behavior-disorder
#14
Farzaneh Rahmani, Mina Ansari, Atefeh Pooyan, Mehdi M Mirbagheri, Mohammad Hadi Aarabi, Farzaneh Rahmani, Mina Ansari, Atefeh Pooyan, Mehdi M Mirbagheri, Mohammad Hadi Aarabi, Mehdi M Mirbagheri, Farzaneh Rahmani, Atefeh Pooyan, Mina Ansari, Mohammad Hadi Aarabi
REM sleep behavior disorder (RBD) is characterized by increased muscle tone and violent limb movements and usually occurs during the early stages of Parkinson disease (PD). PD patients with RBD represent faster motor progression and cognitive dysfunction. We used diffusion imaging to assess which regions are involved in this phenomenon. In the current study, we computed Quantitative Anisotropic (QA), which is based on spin distribution function (SDF) that quantifies the density of diffusing water and is more sensitive to psychological differences between groups and also diffusion MRI connectometry to conduct group analysis between age and gender matched PD patients with and without RBD...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226696/divergence-map-from-diffusion-tensor-imaging-concepts-and-application-to-corpus-callosum
#15
Gustavo R Pinheiro, Guilherme S Soares, Andre Luis Costa, Roberto A Lotufo, Leticia Rittner, Gustavo R Pinheiro, Guilherme S Soares, Andre Luis Costa, Roberto A Lotufo, Leticia Rittner, Leticia Rittner, Gustavo R Pinheiro, Roberto A Lotufo, Andre Luis Costa, Guilherme S Soares
This work proposes a novel approach to the analysis of Diffusion Tensor Imaging (DTI) by applying the mathematical concept of divergence, used in vector analysis. This is achieved by choosing an arbitrary direction of analysis and using this direction to transform the diffusion tensor field into an oriented vector field. The method was inspired by the idea of imposing a liquid flow inside the biological tissues, oriented in the direction of analysis, and watching the direction it would be expected to take as it flows through the paths created by the fibers...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226694/multi-output-gaussian-processes-for-enhancing-resolution-of-diffusion-tensor-fields
#16
Hernan Dario Vargas Cardona, Alvaro A Orozco, Mauricio A Alvarez, Hernan Dario Vargas Cardona, Alvaro A Orozco, Mauricio A Alvarez, Hernan Dario Vargas Cardona, Mauricio A Alvarez, Alvaro A Orozco
Second order diffusion tensor (DT) fields are widely used in several clinical applications: brain fibers connections, diagnosis of neuro-degenerative diseases, image registration, brain conductivity models, etc. However, due to current acquisition protocols and hardware limitations in MRI machines, the diffusion magnetic resonance imaging (dMRI) data is obtained with low spatial resolution (1 or 2 mm(3) for each voxel). This issue can be significant, because tissue fibers are much smaller than voxel size. Interpolation has become in a successful methodology for enhancing spatial resolution of DT fields...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226693/comprehensive-reconstruction-of-multi-shot-multi-channel-diffusion-data-using-mussels
#17
Merry Mani, Vincent Magnotta, Douglas Kelley, Mathews Jacob, Merry Mani, Vincent Magnotta, Douglas Kelley, Mathews Jacob, Mathews Jacob, Vincent Magnotta, Merry Mani, Douglas Kelley
Echo planar imaging (EPI)-based magnetic resonance imaging (MRI) data are often corrupted by Nyquist ghost artifacts resulting from odd-even shifts of the EPI read-outs. Algorithms that corrects for the Nyquist ghost artifacts rely on calibration scans that are collected prior to the data acquisition. However, a more complex pattern of ghosting artifacts arises when diffusion-weighted data are acquired using segmented k-space EPI read-outs. The additional under-sampling present in the segmented acquisitions and the inter-shot motion during diffusion weighted acquistion cause ghosting artifacts in addition to the EPI ghosting arising from odd-even shifts...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226446/a-challenging-issue-detection-of-white-matter-hyperintensities-in-neonatal-brain-mri
#18
Baptiste Morel, Yongchao Xu, Alessio Virzi, Thierry Geraud, Catherine Adamsbaum, Isabelle Bloch, Baptiste Morel, Yongchao Xu, Alessio Virzi, Thierry Geraud, Catherine Adamsbaum, Isabelle Bloch, Alessio Virzi, Yongchao Xu, Thierry Geraud, Catherine Adamsbaum, Isabelle Bloch, Baptiste Morel
The progress of magnetic resonance imaging (MRI) allows for a precise exploration of the brain of premature infants at term equivalent age. The so-called DEHSI (diffuse excessive high signal intensity) of the white matter of premature brains remains a challenging issue in terms of definition, and thus of interpretation. We propose a semi-automatic detection and quantification method of white matter hyperintensities in MRI relying on morphological operators and max-tree representations, which constitutes a powerful tool to help radiologists to improve their interpretation...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226439/optical-imaging-of-functional-connectivity-at-the-bedside
#19
Joseph P Culver, Karla M Bergonzi, Adam E Eggebrecht, Andrew K Fishell, Jin-Moo Lee, Joseph P Culver, Karla M Bergonzi, Adam E Eggebrecht, Andrew K Fishell, Jin-Moo Lee, Andrew K Fishell, Joseph P Culver, Jin-Moo Lee, Karla M Bergonzi, Adam E Eggebrecht
High-density imaging arrays have improved the image quality of diffuse optical tomography (HD-DOT) methods for mapping brain functions. Development of resting state measures of functional connectivity provides a brain assay logistically compatible with bedside imaging in the clinic. In this paper we review these advances and demonstrate the sensitivity of HD-DOT to acute ischemic stroke.
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226410/patient-specific-computational-modeling-of-cortical-spreading-depression-via-diffusion-tensor-imaging
#20
Julia M Kroos, Isabella Marinelli, Ibai Diez, Jesus M Cortes, Sebastiano Stramaglia, Luca Gerardo-Giorda
Cortical Spreading Depression (CSD), a depolarization wave originating in the visual cortex and traveling towards the frontal lobe, is commonly accepted as a correlate of migraine visual aura. As of today, little is known about the mechanisms that can trigger or stop such phenomenon. However, the complex and highly individual characteristics of the brain cortex suggest that the geometry might have a significant impact in supporting or contrasting the propagation of CSD. Accurate patient-specific computational models are fundamental to cope with the high variability in cortical geometries among individuals, but also with the conduction anisotropy induced in a given cortex by the complex neuronal organisation in the grey matter...
February 22, 2017: International Journal for Numerical Methods in Biomedical Engineering
keyword
keyword
55770
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"