• Latency and Echo-Time Dependence of the GRE-BOLD Signal in High-Resolution fMRI. (mpg.de)
  • Prospective slice-by-slice motion correction reduces false positive activations in fMRI with task-correlated motion. (mpg.de)
  • Using high-resolution functional magnetic resonance imaging (fMRI) and multi-voxel pattern analysis (MVPA), we sought to determine the degree to which these complex motor processes are dissociable in basal ganglia and cortical networks. (frontiersin.org)
  • The differences of cognitive data and functional connectivity (FC) in resting-state functional magnetic resonance imaging (rs-fMRI) were compared between the patient group and the NC group. (biomedcentral.com)
  • Their cognitive performance and functional connectivity (FC) in resting-state functional magnetic resonance imaging (rs-fMRI) were compared to 22 healthy children. (biomedcentral.com)
  • Many neuroimaging studies have demonstrated the potential of functional network connectivity patterns estimated from resting functional magnetic resonance imaging (fMRI) to discriminate groups and predict information about individual subjects. (biorxiv.org)
  • Two groups of pulse sequences have revolutionized neuroimaging research, diffusion imaging and functional imaging (fMRI). (humanconnectome.org)
  • Functional magnetic resonance image (fMRI) experiments rely on the ability to detect subtle signal changes in magnetic resonance image time series. (ox.ac.uk)
  • Here, we visualized activations of the cerebellum and extracerebellar regions using high-field fMRI, while we asked participants to observe and imitate images with pictures of human faces expressing different emotional states or with moving geometric shapes as control. (springer.com)
  • Here, we tackled these questions by presenting short video clips of emotion-laden faces to human subjects, while examining the activities of their cerebellum and cortical brain regions using high-field functional magnetic resonance imaging (fMRI) (a 3T MRI scanner). (springer.com)
  • All subjects underwent diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) scans. (researchsquare.com)
  • 1 , 2 Functional magnetic resonance imaging (fMRI), measuring the Blood Oxygen Level Dependent (BOLD) response to neural activation in the olfactory cortex, has particularly enabled the identification of cortical and subcortical brain structures that participate in olfactory processing. (dovepress.com)
  • Random repeating images of high-calorie food designed to engage parts of the brain were presented during the pre and post fMRI scans. (lidsen.com)
  • All participants completed a functional magnetic resonance imaging (fMRI) scan while viewing temporally predictable or unpredictable negative or neutral images. (biomedcentral.com)
  • The aim of the current study was to examine neural responses to predictable and unpredictable aversiveness using functional magnetic resonance imaging (fMRI) in three groups: 1) current PD with comorbid MDD, 2) current MDD-only, and 3) no lifetime history of psychopathology. (biomedcentral.com)
  • In Old World macaque monkeys, Sliwa and Freiwald, 2017 recently identified areas in parietal and frontal cortex that were exclusively activated by the observation of social interactions of other macaques using functional magnetic resonance imaging (fMRI). (elifesciences.org)
  • Center-out echo-planar spectroscopic imaging with correction of gradient-echo phase and time shifts. (mpg.de)
  • Phase-cycled segmented center-out echo planar spectroscopic imaging sequence. (mpg.de)
  • Correction and optimization of symmetric echo-planar spectroscopic imaging for hyperpolarized [1-13C]-pyruvate. (viictr.org)
  • Optimization of white-matter-nulled magnetization prepared rapid gradient echo (MP-RAGE) imaging. (umassmed.edu)
  • Double-shot center-out echo planar spectrocopic imaging at 3 Tesla. (mpg.de)
  • Introduction: 1.5 Tesla (1.5T) remain a significant field strength for brain imaging worldwide. (bvsalud.org)
  • Shared vulnerability of two synaptically-connected medial temporal lobe areas to age and cognitive decline: a seven tesla magnetic resonance imaging study. (umassmed.edu)
  • Sequences that use shorter echo times (e.g., spin echo) may be less susceptible to these artifacts compared to sequences with longer echo times (e.g., echo planar imaging). (mrimaster.com)
  • Correct B0 field inhomogeneity-induced distortion in Echo Planar Images (e.g., diffusion-weighted images) using two images acquired with opposing phase encoding directions. (manpages.org)
  • The image registration procedure accomplishes the tasks of removing the effects of subject motion and eddy current distortion as well as aligning the images to a given template with only one interpolation step, ensuring minimal data quality loss. (grantome.com)
  • We addressed the task of registering DT-MRI data to other structural MRI data contained in the database using rigid body and linear transformations and we are currently experimenting with several non-linear deformation strategies for Echo-Planar Image (EPI) distortion correction. (grantome.com)
  • This is followed by taking the Inverse Fourier transform for reconstruction of the image, which can contain ghosting artifacts. (wikipedia.org)
  • Reducing the echo train length (ETL) or using techniques such as partial Fourier imaging can help mitigate eddy current artifacts. (mrimaster.com)
  • Characterization of and correction for eddy current artifacts in echo planar diffusion imaging. (mrimaster.com)
  • Eddy current artifact in MRI is caused by the interaction of the gradient magnetic fields with the conductive materials present in the imaging subject or surrounding the MRI scanner. (mrimaster.com)
  • These eddy currents can produce additional magnetic fields that cause image distortions and signal losses, resulting in the eddy current artifact. (mrimaster.com)
  • The appearance of eddy current artifact can vary depending on the imaging sequence used and the location of the artifact. (mrimaster.com)
  • The MDD group ( n = 29) and a healthy control group ( n = 47) underwent diffusion tensor imaging (DTI) scans and an analysis was conducted using TBSS. (cambridge.org)
  • Both rely on image formation via the echo planar imaging (EPI) pulse sequence. (humanconnectome.org)
  • Most functional MRI studies rely on fast Echo Planar Imaging, which is sensitive to magnetic susceptibility effects. (vanderbilt.edu)
  • In this study, we adapted a rule attainment task, the Brixton Spatial Anticipation Test ( Burgess and Shallice, 1996 ), to a functional imaging context with the goal of testing the contribution of different prefrontal cortex (PFC) and temporo-parietal regions to rule acquisition and rule following. (jneurosci.org)
  • Echo-planar imaging is an MRI technique that reduces the time of data acquisition to reduce capture of patient movement. (wikipedia.org)
  • Simultaneous acquisition of spatial harmonics (SMASH): fast imaging with radiofrequency coil arrays. (mrimaster.com)
  • Recent computer simulations and clinical studies at 3T MRI have suggested that dynamic susceptibility contrast (DSC) MRI using a 30° flip angle ("low-FA") with model-based leakage correction and no gadolinium-based contrast agent (GBCA) preload provides equivalent relative cerebral blood volume (rCBV) measurements to the reference-standard acquisition using a single-dose GBCA preload with a 60° flip angle ("intermediate-FA") and model-based leakage correction. (bvsalud.org)
  • Robust single-shot T2 mapping via multiple overlapping-echo acquisition and deep neural network. (jjbgyp.com)
  • Increased Speed and Image Quality for Pelvic Single-Shot Fast Spin-Echo Imaging with Variable Refocusing Flip Angles and Full-Fourier Acquisition. (umassmed.edu)
  • Multiecho time-resolved acquisition (META): a high spatiotemporal resolution Dixon imaging sequence for dynamic contrast-enhanced MRI. (umassmed.edu)
  • Ghosting is a visual artifact that occurs in magnetic resonance imaging(MRI) scans. (wikipedia.org)
  • METHODS: Three different correction methods were applied to 53 brain scans: residual water peak alignment, creatine fitting, and spectral registration. (manchester.ac.uk)
  • CONCLUSION: Frequency correction is an important step in processing MRS data, significantly impacting metabolite quantification, particularly after echo-planar imaging that often occurs with MRS scans in clinical studies. (manchester.ac.uk)
  • We present a comparison using in vivo data of different methods for correcting these errors.METHODS: Three different correction methods were applied to 53 brain scans: residual water peak alignment, creatine fitting, and spectral registration. (manchester.ac.uk)
  • All three correction methods produced significantly improved linewidths relative to uncorrected data, with spectral registration performing best by a small margin.CONCLUSION: Frequency correction is an important step in processing MRS data, significantly impacting metabolite quantification, particularly after echo-planar imaging that often occurs with MRS scans in clinical studies. (manchester.ac.uk)
  • Adding diffusion-sensitizing gradients to an imaging sequence (spatial encoding) constitutes the basis for diffusion-weighted MR imaging. (ajronline.org)
  • This information is fed to the scanner host computer to dynamically update the imaging gradients necessary for rigid body realignment of the data to be acquired. (gitlab.io)
  • M2-SE and STEAM can be performed equally well at peak systole at 3 T using standard gradients, but at the sweet-spot and diastole STEAM is more reliable and image quality scores are higher. (biomedcentral.com)
  • However, differences in myocardial position and conformation between the diffusion encoding gradients result in changes in image phase and signal intensity. (biomedcentral.com)
  • Fully automated calculation of image-derived input function in simultaneous PET/MRI in a sheep model. (mpg.de)
  • Lean body mass correction of standardized uptake value in simultaneous whole-body positron emission tomography and magnetic resonance imaging. (mpg.de)
  • Lean body mass correction of standardized uptake values in simultaneous whole-body PET-MRI - Proof of principle trial. (mpg.de)
  • 7. Yao Luo, Jun Zhang, Lin Chen, Shuhui Cai*, Congbo Cai*, Accelerating multi-slice spatiotemporally encoded MRI with simultaneous echo refocusing, Journal of Magnetic Resonance 296 (2018) 12-22. (jjbgyp.com)
  • Simultaneous single- and multi-contrast super-resolution for brain MRI images based on a convolutional neural network, Computers in Biology and Medicine, 99 (2018) 133-141. (jjbgyp.com)
  • Simultaneous T(1) and B(1) (+) mapping using reference region variable flip angle imaging. (umassmed.edu)
  • An efficient 3D stack-of-stars turbo spin echo pulse sequence for simultaneous T2-weighted imaging and T2 mapping. (umassmed.edu)
  • Technological aspects of human brain perfusion imaging by continuous arterial spin labeling. (mpg.de)
  • Adaptive motion correction of single-voxel spectroscopy with real-time frequency correction at 3T and 7T. (mpg.de)
  • Prospective repositioning and motion correction of single voxel spectroscopy at 3T and 7T. (mpg.de)
  • Acquiring diffusion-weighted images with at least two different b values (commonly 20 and 1000 sec/mm 2 ) while keeping the TE fixed allows the determination of the ADC value for each image voxel ( Fig. 3 ). (ajronline.org)
  • Observation of Myelin Water at Ultra-Short Echo Time by Longitudinal Relaxographic Imaging with Spin-Echo Center-out EPI (DEPICTING). (mpg.de)
  • 3D T2-weighted spin echo imaging in the breast. (umassmed.edu)
  • Stimulated-echo (STEAM) and, more recently, motion-compensated spin-echo (M2-SE) techniques have been used for in-vivo diffusion tensor cardiovascular magnetic resonance (DT-CMR) assessment of cardiac microstructure. (biomedcentral.com)
  • Some common features of the artifact include geometric distortions, signal losses, and blurring of the image. (mrimaster.com)
  • ISMRM 2014) Prospective motion correction of 3D EPI data for functional MRI using optical tracking. (gitlab.io)
  • Optically detunable, inductively coupled coil for self-gating in small animal magnetic resonance imaging. (mpg.de)
  • The effects of gradient coil nonlinearities and EPI ghost correction schemes are also discussed. (ox.ac.uk)
  • We then review techniques for acquiring relatively high-resolution diffusion-sensitive MR images and computer-based algorithms that allow the generation of white matter fiber tract maps from the tensor data. (ajronline.org)
  • Several algorithms have been proposed to remove ghosting in the medical images. (wikipedia.org)
  • Nowadays, more advanced segmentation algorithms and higher resolution imaging enable the automated and precise identification of additional retinal layers including the outer retina as well as novel and more precise peripapillary retinal nerve fiber layer (pRNFL) parameters such as Bruch's membrane opening-minimum rim width (BMO-MRW) around the optic disk 13 . (nature.com)
  • This is a post-processing technique which uses the simple motion models (such as translational motion, rotational motion or linear motion) to remove the ghosts that occur in the MR images. (wikipedia.org)
  • We demonstrate a relationship between respiration-related susceptibility effects in the presence of parallel imaging acquisitions and apply our findings to analyze the behavior of IMPACT (IMage-based Physiological Artifact Correction Technique). (vanderbilt.edu)
  • Based on our findings regarding IMPACT, we propose COMPACT (Center of Mass-based Physiological Artifact Correction Technique), a new method which provides a reliable estimate of respiratory effects based on the motion of an image set's center of mass (centroid) through time. (vanderbilt.edu)
  • Ghosting is a multidimensional artifact that occurs in the MRI in the phase encoded direction (short axis of the image) after applying the Fourier transform. (wikipedia.org)
  • When the phase of the magnetic resonance signal is being encoded into the 2-D or 3-D Fourier image, a mild deviation from the actual phase and amplitude may occur. (wikipedia.org)
  • k-space is a graphic matrix of an MR that represents the Fourier transform domain of an image before undergoing the Inverse Fourier transformation.The phase deviations that occur in the k-space of an MR image decide the characteristics of the ghosts that appear in the resulting image. (wikipedia.org)
  • This method was developed based on the fact that the difference between the odd and even virtual k-space data is the Fourier transform of the underlying sparse image. (wikipedia.org)
  • Model-constrained reconstruction accelerated with Fourier-based undersampling for hyperpolarized [1-13 C] pyruvate imaging. (viictr.org)
  • I am an MRI physicist with over twenty-five years of experience in MR physics, pulse sequence development, image reconstruction, and image processing spanning industry (GE) and academia (Stanford, Mayo, UA). (umassmed.edu)
  • The iterative problem solving method is a ghost correction algorithm that removes ghosting that occurs due to the physical movement of the patient. (wikipedia.org)
  • Reference free EPI ghost correction algorithm uses a method called ALOHA (Annihilating filter-based low rank Hankel structured matrix completion approach). (wikipedia.org)
  • Spectral registration proved most effective at frequency correction. (manchester.ac.uk)
  • Here, we resolve this apparent controversy by showing that the conflicting findings can be accounted for when considering the influence of task demands and individual ability on resulting functional magnetic resonance imaging activation patterns. (jneurosci.org)
  • Magnetic Resonance Images (MRI) of the brain are being performed and the imaging findings are being related to the results of standardized neuropsycological tests. (grantome.com)
  • This prospective pilot study used structural and resting-state functional brain magnetic resonance imaging to compare total cortical thickness, cortical surface area, deep gray matter volume and functional connectivity (FC) between 33 patients with NMOSD and 20 healthy controls (HCs). (biomedcentral.com)
  • In particular, the effects of magnetic field inhomogeneities are described, both on echo planar imaging (EPI) data and on spiral imaging data. (ox.ac.uk)
  • Strain information was obtained using cine spiral displacement encoding with stimulated echoes for comparison with DT-CMR results. (biomedcentral.com)
  • Background: This pilot randomised clinical trial investigated the effect of Clinical Emotional Freedom Techniques (EFT) on brain activation in response to food craving stimuli using functional magnetic resonance imaging. (lidsen.com)
  • To explore this hypothesis, we used magnetic resonance imaging (MRI) to compare structural and functional connectivity alterations of potentially important brain regions between NMOSD patients who experience low fatigue or high fatigue, and healthy controls. (biomedcentral.com)
  • The ability to spatially map the diffusion of free water protons in vivo using 1 H MR imaging and the observation that the diffusion of free water protons is reduced in acutely infarcted brain tissue are responsible for the widespread use of these techniques in clinical imaging [ 3 , 4 , 5 , 6 , 7 , 8 ]. (ajronline.org)
  • Diffusion tensor imaging (DTI) provides measurements to investigate the integrity of white matter architecture in vivo. (researchsquare.com)
  • PET, SPECT and MRI are powerful techniques for in vivo molecular imaging. (infn.it)
  • Write Jacobian intensity correction map for forward image. (manpages.org)
  • Phase-cycled SCEPSIS" for rapid metabolic imaging. (mpg.de)
  • Overall I am interested in developing more comprehensive and diagnostically useful disease imaging protocols for evaluation of anatomic, metabolic and functional characteristics of healthy and abnormal tissues. (mcmaster.ca)
  • Furthermore, the authors concentrated on the inner retina and did not consider the outer retina due to technical limitations of retinal imaging at the time 11 , 12 . (nature.com)
  • IE uses a low-amplitude, high-frequency source (often a spring-loaded or solenoid-driven ball bearing) to obtain a frequency-domain measure of the compression wave's travel time between the outer surface and internal planar discontinuities or external boundaries that exhibit an acoustic impedance mismatch. (cdc.gov)
  • Twenty-six healthy young adult participants were presented with a series of images of cards, each consisting of a set of circles numbered in sequence with one colored blue. (jneurosci.org)
  • Previous studies reported associations between SD-OCT assessed retinal structures and magnetic resonance imaging (MRI) assessed brain parameters in small samples of mostly cognitively impaired participants 9 , 10 . (nature.com)
  • The multi-shot echo planar images tend to capture more data than that of the single shot EPI. (wikipedia.org)
  • The occurrence of the Ghosts in the images is converted into missing k-space data and is recovered with the help of the ALOHA matrix. (wikipedia.org)
  • Neuroplasticity was determined by the correlation analysis between cognitive and image data. (biomedcentral.com)
  • When acquiring diffusion data one typically acquires an image where each pixel has information about diffusion along one direction and for some range of diffusivities. (humanconnectome.org)
  • RESULTS: MRS data acquired after DTI imaging exhibited a frequency drift four times higher than data without DTI, resulting in changes to metabolite concentrations, particularly glutamate/glutamine. (manchester.ac.uk)
  • All three correction methods produced significantly improved linewidths relative to uncorrected data, with spectral registration performing best by a small margin. (manchester.ac.uk)
  • An approach to using the XPACE camera system for prospective motion correction of MRI data was implemented for a 3D echo-planar imaging pulse sequence. (gitlab.io)
  • The emergence of massive scale spa-tial data is due to the proliferation of cost effective and ubiquitous positioning technologies, development of high resolution imaging technologies, and contribution from a large number of community users. (emory.edu)
  • These include difficulties in obtaining data from children given their limited ability to comply with procedures, the lack of an adequate normative data base with which to characterize normal brain development and against which to identify and measure aberrant brain development, the lack of adequate image analysis tools for characterizing developmental brain changes, and a lack of an adequate means for sharing data analytic tools. (grantome.com)
  • Specifically we developed procedures for sorting, displaying, and co-registering diffusion weighted images from which the DT-MRI data is computed. (grantome.com)
  • To deal with the effects of strain on the diffusion tensor a correction model has been used with input from 3D strain data [ 12 ]. (biomedcentral.com)
  • My work focuses on assessment of normal and diseased tissue microstructure and the resultant modulation of tissue metabolism using medical imaging technologies. (mcmaster.ca)
  • In the last 10-15 years, MR imaging techniques have been increasingly applied to the study of molecular displacement (diffusion) in biologic tissue [ 1 , 2 ]. (ajronline.org)
  • However, more recently I have focused on applications of multimodal techniques, or the fusion of MRI with EEG, EMG, ultrasound and other imaging methods. (mcmaster.ca)
  • Eddy currents can be more pronounced in fast imaging techniques with longer echo trains. (mrimaster.com)
  • Evidence obtained with low-resolution and low-field functional imaging techniques (PET, 1.5T MRI scanner) also supports the possibility that the cerebellum contributes to the control of emotions, but in these studies, precise localization at the cerebellar sub-regional level remains to be established [ 16 , 18 - 20 ] (Table 1 ). (springer.com)
  • As diagnostic techniques evolve from the systems to the molecular level, the role of multimodality molecular imaging becomes increasingly important. (infn.it)
  • MR Imaging Evaluation of the Kidneys in Patients with Reduced Kidney Function: Noncontrast Techniques Versus Contrast-Enhanced Techniques. (umassmed.edu)
  • Techniques for detecting defects in concrete structures include impulse response (IR) [3] and impact-echo (IE) [4] testing and modal analysis. (cdc.gov)
  • The impulse-response and impact-echo techniques are both essentially drive-point response measurements, as is the miners' roof sounding, where a stimulus is applied and a response is measured in the same, or nearly same, location. (cdc.gov)
  • This kind of motion causes a blur in the phase-encoded direction of the image. (wikipedia.org)
  • After the 180° pulse, the frequency encoding gradient rapidly changes to a negative amplitude and the resulting echos are encoded in the phase encoded axis. (wikipedia.org)
  • Define the phase-encoded image coordinate direction. (manpages.org)
  • Use this switch is the reverse phase-encoded image does not need to be flipped prior to unwarping. (manpages.org)
  • If normal and reverse phase-encoded image display in the same gross orientation in 'triplanar', then flipping is not necessary and must be turned off using this switch. (manpages.org)
  • One of my methods, DISCO, is now a product available on all GE MRI scanners since 2017, and is widely used for prostate and breast imaging worldwide. (umassmed.edu)
  • First embedded in-bore system for fast optical prospective head motion-correction in MRI. (mpg.de)
  • My current research interests are focused on ultra high-resolution imaging and segmentation of deep brain structures like thalamus and hippocampus and the specificity of their involvement in pathology such as alcoholism, multiple sclerosis, Alzheimer's disease, and essential tremor. (umassmed.edu)