Reliability of neuroanatomical measurements in a multisite longitudinal study of youth at risk for psychosis

Abstract

Multi-site longitudinal neuroimaging designs are used to identify differential brain structural change associated with onset or progression of disease. The reliability of neuroanatomical measurements over time and across sites is a crucial aspect of power in such studies. Prior work has found that while within-site reliabilities of neuroanatomical measurements are excellent, between-site reliability is generally more modest. Factors that may increase between-site reliability include standardization of scanner platform and sequence parameters and correction for between-scanner variations in gradient nonlinearities. Factors that may improve both between- and within-site reliability include use of registration algorithms that account for individual differences in cortical patterning and shape. In this study 8 healthy volunteers were scanned twice on successive days at 8 sites participating in the North American Prodrome Longitudinal Study (NAPLS). All sites employed 3 Tesla scanners and standardized acquisition parameters. Site accounted for 2 to 30% of the total variance in neuroanatomical measurements. However, site-related variations were trivial (<1%) among sites using the same scanner model and 12-channel coil or when correcting for between-scanner differences in gradient nonlinearity and scaling. Adjusting for individual differences in sulcal-gyral geometries yielded measurements with greater reliabilities than those obtained using an automated approach. Neuroimaging can be performed across multiple sites at the same level of reliability as at a single site, achieving within- and between-site reliabilities of 0.95 or greater for gray matter density in the majority of voxels in the prefrontal and temporal cortical surfaces as well as for the volumes of most subcortical structures.

Structural Brain Abnormalities in Youth With Psychosis Spectrum Symptoms

“…These brain phenotypes may become a biomarker that can be used in genomic studies, drug discovery, and clinical trials of novel therapeutics. 34,105–108 Especially when used in combination with cognitive testing and measures of polygenic risk 109–112 imaging phenotypes may help evaluate risk and target interventions for youth with PS symptoms before frank psychosis occurs and negative outcomes accrue. Moving forward, development of data-driven analytic techniques to parse heterogeneity 113 within PS youth will accelerate translation to clinical practice.…”

Progressive Reduction in Cortical Thickness as Psychosis Develops: A Multisite Longitudinal Neuroimaging Study of Youth at Elevated Clinical Risk

“…In addition, the ADNI structural phantom was scanned at each site and processed using the AQUAL2 algorithm (36). We have previously reported on phantom-based performance metrics as well as two processing streams applied to the traveling human data: cortical pattern matching and voxel-based morphometry (37). Briefly, the 8 scanners performed within the range of accepted tolerance according to the phantom-based metrics, and all achieved excellent reliabilities for intracranial, brain, gray matter, white matter, and subcortical volumes.…”

Harmonizing Diffusion MRI Data Across Multiple Sites and Scanners

“…Thus, aggregating data sets from different sites is challenging due to the inherent differences in the acquired images from different scanners. Although the inter-site variability of neuroanatomical measurements can be minimized by acquiring images using similar type of scanners (same vendor and version) with similar pulse sequence parameters and same field strength [3], many recent studies have shown that there still exist large differences between diffusion measurements from different sites [4]. This inter-site variability in the measurements can come from several sources, e.g., subject physiological motion, number of head coils used for measurement (16 or 32 channel head coil), imaging gradient non-linearity as well as scanner related factors [5].…”