The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Diffusion tensor imaging (DTI) of the human optic nerve presents challenges from geometric distortion in echo planar imaging (EPI) caused by magnetic field inhomogeneity and partial volume artifacts caused by confounding signals from surrounding fat and cerebrospinal fluid (CSF). A protocol for human optic nerve DTI was developed with geometric distortion correction and suppression of fat and CSF...
Geometric distortion induced by magnetic field inhomogeneity is an intrinsic problem for echo-planar imaging (EPI). Most of the existing correction techniques require separate field map scans in addition to the measurement scans. The effectiveness of these methods requires consistent patient position between these scans, thus inter-scan patient motions degrade the correction results. We propose a...
A practical and reliable method for correction of EPI distortions caused by susceptibility-induced field inhomogeneity is proposed. Our method integrates two existing algorithms, PLACE and SPHERE. We further improve the correction by embedding an upsampling scheme into the algorithms. The upsampling ratio is optimized using simulations. The number of field maps to be averaged in order to reduce noise...
MRI system noise often appears in the fMRI timeseries in phantom and human subjects experiments. The predominant characteristic of this MRI system noise is high amplitude at one or a few specific temporal frequencies. These frequencies are immediately found by FFT analysis, but they have also been identified in ICA methods. This study indicates that these frequencies should be considered in the design...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.