Abstract
As the multi-center studies with resting-state functional magnetic resonance imaging (RS-fMRI) have been more and more applied to neuropsychiatric studies, both intra- and inter-scanner reliability of RS-fMRI are becoming increasingly important. The amplitude of low frequency fluctuation (ALFF), regional homogeneity (ReHo), and degree centrality (DC) are 3 main RS-fMRI metrics in a way of voxel-wise whole-brain (VWWB) analysis. Although the intra-scanner reliability (i.e., test-retest reliability) of these metrics has been widely investigated, few studies has investigated their inter-scanner reliability. In the current study, 21 healthy young subjects were enrolled and scanned with blood oxygenation level dependent (BOLD) RS-fMRI in 3 visits (V1 – V3), with V1 and V2 scanned on a GE MR750 scanner and V3 on a Siemens Prisma. RS-fMRI data were collected under two conditions, eyes open (EO) and eyes closed (EC), each lasting 8 minutes. We firstly evaluated the intra- and inter-scanner reliability of ALFF, ReHo, and DC. Secondly, we measured systematic difference between two scanning visits of the same scanner as well as between two scanners. Thirdly, to account for the potential difference of intra- and inter-scanner local magnetic field inhomogeneity, we measured the difference of relative BOLD signal intensity to the mean BOLD signal intensity of the whole brain between each pair of visits. Last, we used percent amplitude of fluctuation (PerAF) to correct the difference induced by relative BOLD signal intensity. The inter-scanner reliability was much worse than intra-scanner reliability; Among the VWWB metrics, DC showed the worst (both for intra-scanner and inter-scanner comparisons). PerAF showed similar intra-scanner reliability with ALFF and the best reliability among all the 4 metrics. PerAF reduced the influence of BOLD signal intensity and hence increase the inter-scanner reliability of ALFF. For multi-center studies, inter-scanner reliability should be taken into account.
Highlights
With its advantages of being non-invasive, fairly good spatial as well as temporal resolution, and very similar design across studies, resting-state functional magnetic resonance imaging (RS-fMRI) of blood oxygenation level dependent (BOLD) technique is promising for clinical research to reveal abnormal spontaneous brain activity
Since magnetic field inhomogeneity between different scanners could lead to the difference of relative BOLD signal intensity, so we aimed to investigate to what extent the inter-scanner reliability was influenced by the difference of relative BOLD signal intensity between scanners
The intra-scanner reliability was higher than the inter-scanner reliability of all the 4 voxel-wise whole-brain” (VWWB) metrics under both eyes open (EO) and eyes closed (EC) conditions
Summary
With its advantages of being non-invasive, fairly good spatial as well as temporal resolution, and very similar design across studies, resting-state functional magnetic resonance imaging (RS-fMRI) of blood oxygenation level dependent (BOLD) technique is promising for clinical research to reveal abnormal spontaneous brain activity. The intra-scanner reliability (i.e., testretest reliability) of many metrics in RS-fMRI has been investigated, such as the amplitude of low frequency fluctuations (ALFF) (Zuo et al, 2010a; Li et al, 2012; Zuo and Xing, 2014; Somandepalli et al, 2015; Zou et al, 2015), regional homogeneity (ReHo) (Li et al, 2012; Zuo et al, 2013; Somandepalli et al, 2015), seed-based functional connectivity (FC) (Shehzad et al, 2009; Patriat et al, 2013; Pannunzi et al, 2017), group-level dual regression independent component analysis (drICA) (Zuo et al, 2010b), voxel-mirrored homotopic connectivity (VMHC) (Zuo et al, 2010c), graph theory (Wang et al, 2011; Braun et al, 2012; Tomasi and Volkow, 2014; Andellini et al, 2015; Aurich et al, 2015). To map the inter-scanner reliability of every voxel in the whole brain, i.e., “voxel-wise whole-brain” (VWWB) analysis, is needed
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
