eprintid: 10089215
rev_number: 30
eprint_status: archive
userid: 608
dir: disk0/10/08/92/15
datestamp: 2020-01-09 13:50:40
lastmod: 2021-12-09 00:02:03
status_changed: 2020-01-09 13:50:40
type: article
metadata_visibility: show
creators_name: Kowalik, GT
creators_name: Knight, D
creators_name: Steeden, JA
creators_name: Muthurangu, V
title: Perturbed spiral real-time phase-contrast MR with compressive sensing reconstruction for assessment of flow in children
ispublished: inpress
subjects: GOSH
subjects: RFH
divisions: UCL
divisions: B02
divisions: D14
divisions: GA1
keywords: compressive sensing, PCMR, real-time
note: © 2019 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/).
abstract: PURPOSE: we implemented a golden‐angle spiral phase contrast sequence. A commonly used uniform density spiral and a new ‘perturbed’ spiral that produces more incoherent aliases were assessed. The aim was to ascertain whether greater incoherence enabled more accurate Compressive Sensing reconstruction and superior measurement of flow and velocity. METHODS: A range of ‘perturbed’ spiral trajectories based on a uniform spiral trajectory were formulated. The trajectory that produced the most noise‐like aliases was selected for further testing. For in‐silico and in‐vivo experiments, data was reconstructed using total Variation L1 regularisation in the spatial and temporal domains. In‐silico, the reconstruction accuracy of the ‘perturbed’ golden spiral was compared to uniform density golden‐angle spiral. For the in‐vivo experiment, stroke volume and peak mean velocity were measured in 20 children using ‘perturbed’ and uniform density golden‐angle spiral sequences. These were compared to a reference standard gated Cartesian sequence. RESULTS: In‐silico, the perturbed spiral acquisition produced more accurate reconstructions with less temporal blurring (NRMSE ranging from 0.03 to 0.05) than the uniform density acquisition (NRMSE ranging from 0.06 to 0.12). This translated in more accurate results in‐vivo with no significant bias in the peak mean velocity (bias: −0.1, limits: −4.4 to 4.1 cm/s; P = 0.98) or stroke volume (bias: −1.8, limits: −9.4 to 5.8 ml, P = 0.19). CONCLUSION: We showed that a ‘perturbed’ golden‐angle spiral approach is better suited to Compressive Sensing reconstruction due to more incoherent aliases. This enabled accurate real‐time measurement of flow and peak velocity in children.
date: 2019-11-08
date_type: published
publisher: WILEY
official_url: https://doi.org/10.1002/mrm.28065
oa_status: green
full_text_type: pub
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_id: 1716439
doi: 10.1002/mrm.28065
lyricists_name: Knight, Daniel
lyricists_name: Kowalik, Grzegorz
lyricists_name: Muthurangu, Vivek
lyricists_name: Steeden, Jennifer
lyricists_id: DSKNI50
lyricists_id: GKOWA82
lyricists_id: VMUTH99
lyricists_id: JAEDG41
actors_name: Kowalik, Grzegorz
actors_id: GKOWA82
actors_role: owner
full_text_status: public
publication: Magnetic Resonance in Medicine
pages: 15
issn: 1522-2594
citation:        Kowalik, GT;    Knight, D;    Steeden, JA;    Muthurangu, V;      (2019)    Perturbed spiral real-time phase-contrast MR with compressive sensing reconstruction for assessment of flow in children.                   Magnetic Resonance in Medicine        10.1002/mrm.28065 <https://doi.org/10.1002/mrm.28065>.    (In press).    Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10089215/3/Kowalik_Perturbed%20spiral%20real-time%20phase-contrast%20MR%20with%20compressive%20sensing%20reconstruction%20for%20assessment%20of%20flow%20in%20children_AOP.pdf