Consistency of rsfMRI connectivity over 2.5 years and 13 sites using the Canadian Dementia Imaging Protocol, Connectivity Maps Dashboards

The Canadian Dementia Imaging Protocol (CDIP) was developed to harmonize acquisition parameters of various imaging sequences across MRI vendors and acquisition sites.  We evaluated the consistency of brain connectivity maps generated using resting-state functional magnetic resonance imaging (rsfMRI) across 17 visits of a single individual: 3 sessions separated by several months and 6 scanning sites (3 Philips, 3 Siemens). Single time point inter-vendor consistency was also analysed using all previous sites and new ones (in total, 4 Philips, 7 Siemens and 2 GE). 

Provided in these dashboards are the connectivity maps of both parts of the study. Using NIAK (Bellec et al. 2011) we computed for each rsfMRI scan, voxel-wise connectivity maps associated with each of the 7 network templates extracted from a group-level functional brain atlas, namely, the Multiresolution Intrinsic Segmentation Template (MIST) atlas generated from 200 healthy subjects (Urchs et al. 2017). To assess that this single individual observation may be generalizable to other subjects, we compared our consistency findings to that acquired from many subjects (N=26) scanned 10 times over the course of 27 days at a single site (HNU1 dataset) (Zuo et al. 2014).