TY - JOUR
T1 - Free water elimination improves test–retest reproducibility of diffusion tensor imaging indices in the brain: A longitudinal multisite study of healthy elderly subjects
AU - Albi, Angela
AU - Pasternak, Ofer
AU - Minati, Ludovico
AU - Marizzoni, Moira
AU - Bartrés Faz, David
AU - Bargalló, Núria
AU - Bosch, Beatriz
AU - Rossini, Paolo Maria
AU - Marra, Camillo
AU - Müller, Bernhard
AU - Fiedler, Ute
AU - Wiltfang, Jens
AU - Roccatagliata, Luca
AU - Picco, Agnese
AU - Nobili, Flavio Mariano
AU - Blin, Oliver
AU - Sein, Julien
AU - Ranjeva, Jean Philippe
AU - Didic, Mira
AU - Bombois, Stephanie
AU - Lopes, Renaud
AU - Bordet, Régis
AU - Gros Dagnac, Hélène
AU - Payoux, Pierre
AU - Zoccatelli, Giada
AU - Alessandrini, Franco
AU - Beltramello, Alberto
AU - Ferretti, Antonio
AU - Caulo, Massimo
AU - Aiello, Marco
AU - Cavaliere, Carlo
AU - Soricelli, Andrea
AU - Parnetti, Lucilla
AU - Tarducci, Roberto
AU - Floridi, Piero
AU - Tsolaki, Magda
AU - Constantinidis, Manos
AU - Drevelegas, Antonios
AU - Frisoni, Giovanni
AU - Jovicich, Jorge
PY - 2017
Y1 - 2017
N2 - Free water elimination (FWE) in brain diffusion MRI has been shown to improve tissue specificity in human white matter characterization both in health and in disease. Relative to the classical diffusion tensor imaging (DTI) model, FWE is also expected to increase sensitivity to microstructural changes in longitudinal studies. However, it is not clear if these two models differ in their test–retest reproducibility. This study compares a bi-tensor model for FWE with DTI by extending a previous longitudinal-reproducibility 3T multisite study (10 sites, 7 different scanner models) of 50 healthy elderly participants (55–80 years old) scanned in two sessions at least 1 week apart. We computed the reproducibility of commonly used DTI metrics (FA: fractional anisotropy, MD: mean diffusivity, RD: radial diffusivity, and AXD: axial diffusivity), derived either using a DTI model or a FWE model. The DTI metrics were evaluated over 48 white-matter regions of the JHU-ICBM-DTI-81 white-matter labels atlas, and reproducibility errors were assessed. We found that relative to the DTI model, FWE significantly reduced reproducibility errors in most areas tested. In particular, for the FA and MD metrics, there was an average reduction of approximately 1% in the reproducibility error. The reproducibility scores did not significantly differ across sites. This study shows that FWE improves sensitivity and is thus promising for clinical applications, with the potential to identify more subtle changes. The increased reproducibility allows for smaller sample size or shorter trials in studies evaluating biomarkers of disease progression or treatment effects. Hum Brain Mapp 38:12–26, 2017. © 2016 Wiley Periodicals, Inc.
AB - Free water elimination (FWE) in brain diffusion MRI has been shown to improve tissue specificity in human white matter characterization both in health and in disease. Relative to the classical diffusion tensor imaging (DTI) model, FWE is also expected to increase sensitivity to microstructural changes in longitudinal studies. However, it is not clear if these two models differ in their test–retest reproducibility. This study compares a bi-tensor model for FWE with DTI by extending a previous longitudinal-reproducibility 3T multisite study (10 sites, 7 different scanner models) of 50 healthy elderly participants (55–80 years old) scanned in two sessions at least 1 week apart. We computed the reproducibility of commonly used DTI metrics (FA: fractional anisotropy, MD: mean diffusivity, RD: radial diffusivity, and AXD: axial diffusivity), derived either using a DTI model or a FWE model. The DTI metrics were evaluated over 48 white-matter regions of the JHU-ICBM-DTI-81 white-matter labels atlas, and reproducibility errors were assessed. We found that relative to the DTI model, FWE significantly reduced reproducibility errors in most areas tested. In particular, for the FA and MD metrics, there was an average reduction of approximately 1% in the reproducibility error. The reproducibility scores did not significantly differ across sites. This study shows that FWE improves sensitivity and is thus promising for clinical applications, with the potential to identify more subtle changes. The increased reproducibility allows for smaller sample size or shorter trials in studies evaluating biomarkers of disease progression or treatment effects. Hum Brain Mapp 38:12–26, 2017. © 2016 Wiley Periodicals, Inc.
KW - Anatomy
KW - Neurology
KW - Neurology (clinical)
KW - Nuclear Medicine and Imaging
KW - Radiological and Ultrasound Technology
KW - Radiology
KW - brain diffusion tensor imaging
KW - free-water imaging
KW - healthy elderly
KW - longitudinal
KW - multisite diffusion MRI
KW - test–retest reproducibility
KW - Anatomy
KW - Neurology
KW - Neurology (clinical)
KW - Nuclear Medicine and Imaging
KW - Radiological and Ultrasound Technology
KW - Radiology
KW - brain diffusion tensor imaging
KW - free-water imaging
KW - healthy elderly
KW - longitudinal
KW - multisite diffusion MRI
KW - test–retest reproducibility
UR - https://publicatt.unicatt.it/handle/10807/93768
UR - https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=84981340827&origin=inward
UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84981340827&origin=inward
U2 - 10.1002/hbm.23350
DO - 10.1002/hbm.23350
M3 - Article
SN - 1065-9471
VL - 38
SP - 12
EP - 26
JO - Human Brain Mapping
JF - Human Brain Mapping
IS - 1
ER -