TY - JOUR
T1 - Dependence of apparent diffusion coefficient measurement on diffusion gradient direction and spatial position – A quality assurance intercomparison study of forty-four scanners for quantitative diffusion-weighted imaging
AU - for the Italian Association of Physics in Medicine (AIFM) Working Group on MR Intercomparison
AU - Fedeli, Luca
AU - Belli, Giacomo
AU - Ciccarone, Antonio
AU - Coniglio, Angela
AU - Esposito, Marco
AU - Giannelli, Marco
AU - Mazzoni, Lorenzo Nicola
AU - Nocetti, Luca
AU - Sghedoni, Roberto
AU - Tarducci, Roberto
AU - Altabella, Luisa
AU - Belligotti, Eleonora
AU - Benelli, Matteo
AU - Betti, Margherita
AU - Caivano, Rocchina
AU - Carni', Marco
AU - Chiappiniello, Andrea
AU - Cimolai, Sara
AU - Cretti, Fabiola
AU - Fulcheri, Christian
AU - Gasperi, Chiara
AU - Giacometti, Mara
AU - Levrero, Fabrizio
AU - Lizio, Domenico
AU - Maieron, Marta
AU - Marzi, Simona
AU - Mascaro, Lorella
AU - Mazzocchi, Silvia
AU - Meliado', Gabriele
AU - Morzenti, Sabrina
AU - Noferini, Linhsia
AU - Oberhofer, Nadia
AU - Quattrocchi, Maria Grazia
AU - Ricci, Alessandra
AU - Taddeucci, Adriana
AU - Tenori, Leonardo
AU - Luchinat, Claudio
AU - Gobbi, Gianni
AU - Gori, Cesare
AU - Busoni, Simone
PY - 2018/1/1
Y1 - 2018/1/1
N2 - Purpose: To propose an MRI quality assurance procedure that can be used for routine controls and multi-centre comparison of different MR-scanners for quantitative diffusion-weighted imaging (DWI). Materials and methods: 44 MR-scanners with different field strengths (1 T, 1.5 T and 3 T) were included in the study. DWI acquisitions (b-value range 0–1000 s/mm2), with three different orthogonal diffusion gradient directions, were performed for each MR-scanner. All DWI acquisitions were performed by using a standard spherical plastic doped water phantom. Phantom solution ADC value and its dependence with temperature was measured using a DOSY sequence on a 600 MHz NMR spectrometer. Apparent diffusion coefficient (ADC) along each diffusion gradient direction and mean ADC were estimated, both at magnet isocentre and in six different position 50 mm away from isocentre, along positive and negative AP, RL and HF directions. Results: A good agreement was found between the nominal and measured mean ADC at isocentre: more than 90% of mean ADC measurements were within 5% from the nominal value, and the highest deviation was 11.3%. Away from isocentre, the effect of the diffusion gradient direction on ADC estimation was larger than 5% in 47% of included scanners and a spatial non uniformity larger than 5% was reported in 13% of centres. Conclusion: ADC accuracy and spatial uniformity can vary appreciably depending on MR scanner model, sequence implementation (i.e. gradient diffusion direction) and hardware characteristics. The DWI quality assurance protocol proposed in this study can be employed in order to assess the accuracy and spatial uniformity of estimated ADC values, in single- as well as multi-centre studies.
AB - Purpose: To propose an MRI quality assurance procedure that can be used for routine controls and multi-centre comparison of different MR-scanners for quantitative diffusion-weighted imaging (DWI). Materials and methods: 44 MR-scanners with different field strengths (1 T, 1.5 T and 3 T) were included in the study. DWI acquisitions (b-value range 0–1000 s/mm2), with three different orthogonal diffusion gradient directions, were performed for each MR-scanner. All DWI acquisitions were performed by using a standard spherical plastic doped water phantom. Phantom solution ADC value and its dependence with temperature was measured using a DOSY sequence on a 600 MHz NMR spectrometer. Apparent diffusion coefficient (ADC) along each diffusion gradient direction and mean ADC were estimated, both at magnet isocentre and in six different position 50 mm away from isocentre, along positive and negative AP, RL and HF directions. Results: A good agreement was found between the nominal and measured mean ADC at isocentre: more than 90% of mean ADC measurements were within 5% from the nominal value, and the highest deviation was 11.3%. Away from isocentre, the effect of the diffusion gradient direction on ADC estimation was larger than 5% in 47% of included scanners and a spatial non uniformity larger than 5% was reported in 13% of centres. Conclusion: ADC accuracy and spatial uniformity can vary appreciably depending on MR scanner model, sequence implementation (i.e. gradient diffusion direction) and hardware characteristics. The DWI quality assurance protocol proposed in this study can be employed in order to assess the accuracy and spatial uniformity of estimated ADC values, in single- as well as multi-centre studies.
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U2 - 10.1016/j.ejmp.2018.09.007
DO - 10.1016/j.ejmp.2018.09.007
M3 - Article
AN - SCOPUS:85055023482
VL - 55
SP - 135
EP - 141
JO - Physica Medica
JF - Physica Medica
SN - 1120-1797
ER -