Multi-site harmonization of diffusion MRI data in a registration framework.
Diffusion MRI (dMRI) data acquired on different scanners varies significantly in its content throughout the brain even if the acquisition parameters are nearly identical. Thus, proper harmonization of such data sets is necessary to increase the sample size and thereby the statistical power of neuroimaging studies. In this paper, we present a novel approach to harmonize dMRI data (the raw signal, instead of dMRI derived measures such as fractional anisotropy) using rotation invariant spherical harmonic (RISH) features embedded within a multi-modal image registration framework. All dMRI data sets from all sites are registered to a common template and voxel-wise differences in RISH features between sites at a group level are used to harmonize the signal in a subject-specific manner. We validate our method on diffusion data acquired from seven different sites (two GE, three Philips, and two Siemens scanners) on a group of age-matched healthy subjects. We demonstrate the efficacy of our method by statistically comparing diffusion measures such as fractional anisotropy, mean diffusivity and generalized fractional anisotropy across these sites before and after data harmonization. Validation was also done on a group oftest subjects, which were not used to "learn" the harmonization parameters. We also show results using TBSS before and after harmonization for independent validation of the proposed methodology. Using synthetic data, we show that any abnormality in diffusion measures due to disease is preserved during the harmonization process. Our experimental results demonstrate that, for nearly identical acquisition protocol across sites, scanner-specific differences in the signal can be removed using the proposed method in a model independent manner.
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA. hengameh.mirzaalian@gmail.com.|Harvard Medical School and Boston Children's Hospital, Boston, MA, USA. hengameh.mirzaalian@gmail.com.
Hengameh
H
Mirzaalian
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Lipeng
L
Ning
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Peter
P
Savadjiev
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Ofer
O
Pasternak
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Sylvain
S
Bouix
University of Waterloo, Waterloo, ON, Canada.
Oleg
O
Michailovich
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Sarina
S
Karmacharya
Stanford University Medical Center (Previously Duke University), Palo Alto, CA, USA.
Gerald
G
Grant
Medical Center and VA Mid-Atlantic MIRECC, Duke University, Durham, NC, USA.
Christine E
CE
Marx
Medical Center and VA Mid-Atlantic MIRECC, Duke University, Durham, NC, USA.
Rajendra A
RA
Morey
Hanover and Geisel School of Medicine at Dartmouth, Dartmouth University, Hanover, NH, USA.
Laura A
LA
Flashman
Ralph H. Johnson VA Medical Center, Medical University of South Carolina, Charleston, SC, USA.
Mark S
MS
George
Geisel School of Medicine at Dartmouth (original) and Indiana University School of Medicine (current), 1 Rope Ferry Rd, Hanover, NH, 03755, USA.
Thomas W
TW
McAllister
Department of Neurosurgery, University of Cincinnati (UC) College of Medicine; Neurotrauma Center at UC Neuroscience Institute; and Mayfield Clinic, Cincinnati, OH, USA.
Norberto
N
Andaluz
University of Pittsburgh School of Medicine (Previously University of Cincinnati), Pittsburgh, PA, USA.
Lori
L
Shutter
Department of Surgery, University of California, San Diego, CA, USA.
Raul
R
Coimbra
Spaulding Rehabilitation Hospital and Harvard Medical School, Boston, MA, USA.
Ross D
RD
Zafonte
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Mike J
MJ
Coleman
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Marek
M
Kubicki
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Carl-Fredrik
CF
Westin
University of California, San Diego, San Diego, CA, USA.
Murray B
MB
Stein
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.|VA Boston Healthcare System, Boston, MA, USA.
Martha E
ME
Shenton
Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Yogesh
Y
Rathi
D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D003198:Computer Simulation; D038524:Diffusion Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D008959:Models, Neurological
Diffusion MRI; Harmonization; Inter-scanner; Intra-site; Multi-site