{"id":2,"date":"2018-10-19T16:17:20","date_gmt":"2018-10-19T16:17:20","guid":{"rendered":"https:\/\/my.dev.vanderbilt.edu\/memento\/?page_id=2"},"modified":"2019-12-10T18:34:41","modified_gmt":"2019-12-10T18:34:41","slug":"sample-page","status":"publish","type":"page","link":"https:\/\/my.dev.vanderbilt.edu\/memento\/sample-page\/","title":{"rendered":"Sub-Challenge #1"},"content":{"rendered":"<p><b>Challenge name<\/b><\/p>\n<p><span style=\"font-weight: 400\">The signal forecast: generalizability of diffusion signal representations<\/span><\/p>\n<p><b>Purpose and relevance of the challenge<\/b><\/p>\n<p><span style=\"font-weight: 400\">With this challenge we aim <\/span><b>to understand the current ability<\/b><span style=\"font-weight: 400\"> of the field at <\/span><b>describing the signal measured in diffusion MRI<\/b><span style=\"font-weight: 400\">. The challenge consists of a number of signals sampled from datasets acquired in human and mice with different diffusion sequences. <\/span><b>Participants will be provided<\/b><span style=\"font-weight: 400\"> with a <\/span><b>subsampled set<\/b><span style=\"font-weight: 400\"> of the acquired data <\/span><b>and are asked to predict<\/b><span style=\"font-weight: 400\"> the remaining &#8211; unseen &#8211; data. The acquired data includes different types of acquisition strategies, such as <\/span><b>multi-shell and DSI-like<\/b><span style=\"font-weight: 400\"> pulsed gradient spin-echo (<\/span><b>PGSE<\/b><span style=\"font-weight: 400\">) [<\/span><span style=\"font-weight: 400\">1]<\/span><span style=\"font-weight: 400\">, as well as double diffusion encoding (<\/span><b>DDE<\/b><span style=\"font-weight: 400\">) [<\/span><span style=\"font-weight: 400\">2]<\/span><span style=\"font-weight: 400\"> and double oscillating diffusion encoding (<\/span><b>DODE<\/b><span style=\"font-weight: 400\">) [<\/span><span style=\"font-weight: 400\">3]<\/span><span style=\"font-weight: 400\">, suitable for a large number of fit approaches. The outcome of this challenge will allow to objectively evaluate the <\/span><b>generalizability and appropriateness<\/b><span style=\"font-weight: 400\">\u00a0of current techniques.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><b>Datasets<\/b><\/p>\n<p><span style=\"font-weight: 400\">The challenge includes <\/span><b>in-vivo brain<\/b><span style=\"font-weight: 400\"> data sampled with <\/span><b>PGSE<\/b><span style=\"font-weight: 400\"> in a <\/span><b>human<\/b><span style=\"font-weight: 400\"> volunteer, and with <\/span><b>DDE \/ DODE <\/b><span style=\"font-weight: 400\">in<\/span><b> mice, ex-vivo<\/b><span style=\"font-weight: 400\">. You can choose which acquisition you would like to predict, and can choose any or all acquisitions strategies.<\/span><\/p>\n<p><span style=\"font-weight: 400\">The two provided datasets are composed as follows:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400\"><b>PGSE<\/b><span style=\"font-weight: 400\">. A subset of the data measured in five voxels, representative of different tissue configurations, extracted from the MASSIVE dataset<\/span><span style=\"font-weight: 400\">4<\/span><span style=\"font-weight: 400\"> (3820 unique diffusion-weighted volumes). The signals measured in each voxel include <\/span><b>2580<\/b><span style=\"font-weight: 400\"> unique <\/span><b>data points<\/b><span style=\"font-weight: 400\"> acquired with a <\/span><b>multi-shell strategy<\/b><span style=\"font-weight: 400\">, and <\/span><b>1240 data points<\/b><span style=\"font-weight: 400\"> acquired with a <\/span><b>DSI-like strategy<\/b><span style=\"font-weight: 400\">. The two acquisitions were collected in 19 separate sessions. The multi-shell and the DSI-like sequence were <\/span><span style=\"font-weight: 400\">NOT<\/span><span style=\"font-weight: 400\"> performed with identical imaging parameters, but with identical diffusion gradients settings. Participants can choose whether they prefer to work with the multi-shell or the DSI-like acquisition. <\/span><\/li>\n<li style=\"font-weight: 400\"><b>DDE and DODE<\/b><span style=\"font-weight: 400\">. A subset of the data from five voxels acquired in a mouse brain, representative of different tissue configurations will be provided. The full dataset consists of <\/span><b>DDE with 2 different diffusion times<\/b><span style=\"font-weight: 400\"> and <\/span><b>DODE with 5 different frequencies<\/b><span style=\"font-weight: 400\">, with 5 b- values and 72 directions each (2520 diffusion weighted volumes in total).<\/span><\/li>\n<\/ul>\n<p><strong>Link to Data :\u00a0See Registration and Data\u00a0Access page<\/strong><\/p>\n<p><b>Participation (Data given to the participants)<\/b><\/p>\n<p><span style=\"font-weight: 400\">Participants will be provided with <\/span><b>part of the measured signals<\/b><span style=\"font-weight: 400\"> for<\/span><b> 5 different tissue configurations<\/b><span style=\"font-weight: 400\">. Additionally, they will receive complete details of the acquisition protocol (imaging parameters, diffusion gradients properties) corresponding to the measured data, including both provided and unseen signals. Regarding multi-shell PGSE, we will provide, for each signal, 495 of the 2580 diffusion-weighted measurements, as well as 20 b = 0s\/mm<\/span><span style=\"font-weight: 400\">2<\/span><span style=\"font-weight: 400\">. Regarding DSI-like PGSE, we provide 480 of the 1240 measured points and 20 b = 0s\/mm<\/span><span style=\"font-weight: 400\">2<\/span><span style=\"font-weight: 400\">. The signals will be distributed in text format in separate files for each acquisition strategy, and do not correspond to the same voxels. For the DDE\/DODE data we will provide data from 1 DDE and 3 DODE waveforms with 4 b-values and 72 directions each (1152 \/ 2520 measurements). Each text file will contain the signal in floating format, with each column representing a different signal, and each row a measurement. The acquisitions details of each measurement can be found in a companion text file \u201c*_AcqParams.txt\u201d. <\/span><b>Sample scripts<\/b><span style=\"font-weight: 400\"> to load the data and the acquisitions details <\/span><b>will be provided<\/b><span style=\"font-weight: 400\"> for popular working environments (MATLAB, Python, C\/C++).<\/span><\/p>\n<p><b>Submission<\/b><\/p>\n<p><span style=\"font-weight: 400\">Participants are asked to submit signal predictions of the unseen data for one of the provided datasets. We ask to submit a zip file containing a textual description of the performed analysis (info.txt) together with the signal predictions (submission.txt). <\/span><\/p>\n<p><span style=\"font-weight: 400\">Please include the following details in the info.txt:<\/span><\/p>\n<ol>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">the submission name and abbreviation;<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">the team name;<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">team members who made meaningful contributions and their affiliation;<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">a brief one sentence submission description;<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">an extended submission description (optional);<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">all relevant citations;<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">observations (optional);<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">relevant discussion points (optional);<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">type of model (signal\/tissue);<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">number of free parameters;<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">pre-processing on the signals (if any);<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">outlier rejection strategy (if any);<\/span><\/li>\n<\/ol>\n<p><span style=\"font-weight: 400\">Also, we encourage submissions of models even when suited for only part of the data, as the scope of the challenge goes well beyond the pure prediction. In such case, please mention in the info.txt\u00a0which points are disregarded by your submission.<\/span><\/p>\n<p><span style=\"font-weight: 400\">The name of the zip file does not matter, however the names of the text files are critical. The predictions must be in the same format of the provided signals, with one column per signal (in the corresponding order), and one row for each measurement specified in the acquisition details of the unprovided data. Predictions of multiple acquisitions strategies (i.e. PGSE DSI-like vs PGSE multi-shell) must be submitted individually (i.e. submit each prediction independently). Although not required, we warmly welcome predictions for multiple datasets (PGSE and DDE\/DODE).<\/span><\/p>\n<p>Example submissions files will be made available with the data.<\/p>\n<p><b>Evaluation<\/b><\/p>\n<p><span style=\"font-weight: 400\">Each submission will be evaluated by computing the weighted averaged mean squared error (MSE) between the provided predictions and the corresponding undisclosed data. In case of N points corresponding to a single diffusion weighting (e.g. shell), these will weighted as 1 single point. Three winners will be selected independently for PGSE (shells and grids will be scored together), DDE and DODE. <\/span><\/p>\n<p><strong>How to get the data<\/strong><\/p>\n<p>Please see &#8220;Registration and Data Access&#8221; Page.<\/p>\n<p><b>References<\/b><\/p>\n<ol>\n<li><span style=\"font-weight: 400\">Stejskal, E. O. &amp; Tanner, J. E. Spin Diffusion Measurements: Spin Echoes in the Presence of a Time-Dependent Field Gradient. <\/span><i><span style=\"font-weight: 400\">J. Chem. Phys.<\/span><\/i> <b>42<\/b><span style=\"font-weight: 400\">, (1965).<\/span><\/li>\n<li><span style=\"font-weight: 400\">Shemesh, N., \u00d6zarslan, E., Komlosh, M. E., Basser, P. J. &amp; Cohen, Y. From single-pulsed field gradient to double-pulsed field gradient MR: Gleaning new microstructural information and developing new forms of contrast in MRI. <\/span><i><span style=\"font-weight: 400\">NMR Biomed.<\/span><\/i> <b>23<\/b><span style=\"font-weight: 400\">, 757\u2013780 (2010).<\/span><\/li>\n<li><span style=\"font-weight: 400\">Ianu\u015f, A. <\/span><i><span style=\"font-weight: 400\">et al.<\/span><\/i><span style=\"font-weight: 400\"> Accurate estimation of microscopic diffusion anisotropy and its time dependence in the mouse brain. <\/span><i><span style=\"font-weight: 400\">Neuroimage<\/span><\/i> <b>183<\/b><span style=\"font-weight: 400\">, 934\u2013949 (2018).<\/span><\/li>\n<li><span style=\"font-weight: 400\">Froeling, M., Tax, C. M. W., Vos, S. B., Luijten, P. R. &amp; Leemans, A. \u2018MASSIVE\u2019 brain dataset: Multiple acquisitions for standardization of structural imaging validation and evaluation. <\/span><i><span style=\"font-weight: 400\">Magn. Reson. Med.<\/span><\/i> <b>77<\/b><span style=\"font-weight: 400\">, 1797\u20131809 (2017).<\/span><\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Challenge name The signal forecast: generalizability of diffusion signal representations Purpose and relevance of the challenge With this challenge we aim to understand the current ability of the field at describing the signal measured in diffusion MRI. The challenge consists &hellip; <a href=\"https:\/\/my.dev.vanderbilt.edu\/memento\/sample-page\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1920,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-2","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/my.dev.vanderbilt.edu\/memento\/wp-json\/wp\/v2\/pages\/2","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/my.dev.vanderbilt.edu\/memento\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/my.dev.vanderbilt.edu\/memento\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/my.dev.vanderbilt.edu\/memento\/wp-json\/wp\/v2\/users\/1920"}],"replies":[{"embeddable":true,"href":"https:\/\/my.dev.vanderbilt.edu\/memento\/wp-json\/wp\/v2\/comments?post=2"}],"version-history":[{"count":15,"href":"https:\/\/my.dev.vanderbilt.edu\/memento\/wp-json\/wp\/v2\/pages\/2\/revisions"}],"predecessor-version":[{"id":166,"href":"https:\/\/my.dev.vanderbilt.edu\/memento\/wp-json\/wp\/v2\/pages\/2\/revisions\/166"}],"wp:attachment":[{"href":"https:\/\/my.dev.vanderbilt.edu\/memento\/wp-json\/wp\/v2\/media?parent=2"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}