DOI: 10.6076/d1159c
title: Closed-loop control of k-space sampling via physiologic feedback for cine MRI

description: This dataset accompanies the manuscript outlining a method for closed-loop
 sampling of k-space in response to physiologic changes. The closed-loop
 approach enables near-uniform radial sampling in a segmented acquisition
 approach which was higher than predetermined golden-angle radial sampling.
 This can be utilized to increase the sampling or decrease the temporal
 footprint of an acquisition and the closed-loop framework has the
 potential to be applied to patients with complex heart rhythms. Briefly,
 Segmented cine cardiac MRI combines data from multiple heartbeats to
 achieve high spatiotemporal resolution cardiac images, yet predefined
 k-space segmentation trajectories can lead to suboptimal k-space sampling.
 In this work, we developed and evaluated an autonomous and closed-loop
 control system for radial k-space sampling to increase sampling
 uniformity. The dataset includes both the algorithm and the data used in
 our manuscript. Our closed-loop system autonomously selects radial k-space
 sampling trajectory during live segmented cine MRI and attempts to
 optimize angular sampling uniformity by selecting views in regions of
 k-space that were not previously well-sampled. Sampling uniformity and
 robustness to arrhythmias was assessed using ECG data acquired from 10
 normal subjects in an MRI scanner. The approach was then implemented with
 a fast gradient echo sequence on a whole-body clinical MRI scanner and
 imaging was performed in 4 healthy volunteers. The closed-loop k-space
 trajectory was compared to random, uniformly distributed and golden angle
 view trajectories via measurement of k-space uniformity and the point
 spread function. Lastly, an arrhythmic dataset was used to evaluate a
 potential application of the approach. The autonomous trajectory increased
 k-space sampling uniformity by 15±7%, main lobe point spread function
 (PSF) signal intensity by 6±4%, and reduced ringing relative to golden
 angle sampling. When implemented, the autonomous pulse sequence prescribed
 radial view angles faster than the scan TR (0.98 ± 0.01 ms, maximum = 1.38
 ms) and increased k-space sampling mean uniformity by 10±11%, decreased
 uniformity variability by 44±12%, and increased PSF signal ratio by 6±6%
 relative to golden angle sampling. This data is shared with Creative
 Commons CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
description: ECGs in 10 normal subjects were recorded while in an MRI scanner
 for evaluation of the approach. Imaging data using the
 method was acquired in 4 normal subjects. 
description: The code utilizes Matlab to do the analysis of ECG data. Image
 reconstruction utilizes other publically available tools
   Links to publications that cite or use the
 data:<br clear="none"> <br clear="none">
 The manuscript for this data is:<br clear="none">
 Contijoch et al. Closed-loop control of k-space sampling via physiologic
 feedback for cine MRI. https://www.medrxiv.org/content/10.1101/2020.06.22.20137638v1<br clear="none"> <br clear="none"> Please cite the dataset as:<br clear="none"> Contijoch, Francisco (2020), Closed-loop control of k-space sampling via physiologic feedback for cine MRI, Dryad, Dataset, https://doi.org/10.6076/D1159C<br clear="none"> <br clear="none"> DATA & FILE OVERVIEW<br clear="none"> <br clear="none"> File List: The set consists of 9 zip files.<br clear="none"> code.zip - Matlab files for closed-loop ECG sampling based control of MRI k-space sampling<br clear="none"> Simulation_Data.zip  - ECG recordings of 10 humans for simulation of MRI sampling with ARKS<br clear="none"> Simulation_Analysis.zip - Code which performs simulation experiments<br clear="none"> Simulation_Results.zip - Results of simulation used for publication<br clear="none"> <br clear="none"> Human_Data.zip  - Data from acquisitions with ARKS on clinical MRI scanner<br clear="none"> Human_Analysis.zip - Code which analyzes in-vivo experiments<br clear="none"> Human_Results.zip - Results of human imaging used for publication