Open AccessImage-derived mean velocity measurement for prediction of coronary flow reserve in a canonical stenosis phantom using magnetic particle imaging
Author(s) -
Robert Siepmann,
Henning Nilius,
Florian Mueller,
Katrin Mueller,
Claudio Luisi,
Seyed Mohammadali Dadfar,
M. Straub,
Volkmar Schulz,
Sebastian Reinartz
Publication year - 2021
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0249697
Subject(s) - imaging phantom , magnetic particle imaging , hyperaemia , calibration , biomedical engineering , materials science , flow velocity , blood flow , flow (mathematics) , nuclear medicine , physics , medicine , mechanics , magnetic nanoparticles , radiology , nanoparticle , nanotechnology , quantum mechanics
Aim of this study is to evaluate whether magnetic particle imaging (MPI) is capable of measuring velocities occurring in the coronary arteries and to compute coronary flow reserve (CFR) in a canonical phantom as a preliminary study. Methods For basic velocity measurements, a circulation phantom was designed containing replaceable glass tubes with three varying inner diameters, matching coronary-vessel diameters. Standardised boluses of superparamagnetic-iron-oxide-nanoparticles were injected and visualised by MPI. Two image-based techniques were competitively applied to calibrate the respective glass tube and to compute the mean velocity: full-duration-at-half-maximum (FDHM) and tracer dilution (TD) method. For CFR-calculation, four necessary settings of the circulation model of a virtual vessel with an inner diameter of 4 mm were generated using differently sized glass tubes and a stenosis model. The respective velocities in stenotic glass tubes were computed without recalibration. Results On velocity level, comparison showed a good agreement ( r FDHM = 0.869, r TD = 0.796) between techniques, preferably better for 4 mm and 6 mm inner diameter glass tubes. On CFR level MPI-derived CFR-prediction performed considerably inferior with a relative error of 20–44%. Conclusions MPI has the ability to reliably measure coronary blood velocities at rest as well as under hyperaemia and therefore may be suitable for CFR calculation. Calibration-associated accuracy of CFR-measurements has to be improved substantially in further studies.