Test-retest reliability of FreeSurfer-derived volume, area and cortical thickness from MPRAGE and MP2RAGE brain MRI
Graham N Knussmann1, Jeffrey S Anderson1, Molly B D Prigge1
1Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA.
Background And Purpose:
Large MRI studies often pool data gathered from widely varying imaging sequences. Pooled data creates a potential source of variation in structural analyses which may cause misinterpretation of findings. The purpose of this study is to determine if data acquired using different scan sequences, head coils and scanners offers consistent structural measurements.
Materials And Methods:
Participants (163 right-handed males: 82 typically developing controls, 81 participants with autism spectrum disorder) were scanned on the same day using an MPRAGE sequence with a 12-channel headcoil on a Siemens 3T Trio scanner and an MP2RAGE sequence with a 64-channel headcoil on a Siemens 3T Prisma scanner. Segmentation was performed using FreeSurfer to identify regions exhibiting variation between sequences on measures of volume, surface area, and cortical thickness. Intraclass correlation coefficient (ICC) and mean percent difference (MPD) were used as test-retest reproducibility measures.
Results:
ICC for total brain segmented volume yielded a 0.99 intraclass correlation, demonstrating high overall volumetric reproducibility. Comparison of individual regions of interest resulted in greater variation. Volumetric variability, although low overall, was greatest in the entorhinal cortex (ICC = 0.71), frontal (ICC = 0.60) and temporal (ICC = 0.60) poles. Surface area variability was greatest in the insula (ICC = 0.65), temporal (ICC = 0.64) and frontal (ICC = 0.68) poles. Cortical thickness was most variable in the frontal (ICC = 0.41) and temporal (ICC = 0.35) poles.
Conclusion:
Data collected on different scanners and head coils using MPRAGE and MP2RAGE are generally consistent for surface area and volume estimates. However, regional variability may constrain accuracy in some regions and cortical thickness measurements exhibit higher generalized variability.
Insights
Pooled MRI data from different scanners show consistent brain volume and surface area measurements. However, some brain regions and cortical thickness measures exhibit higher variability, potentially impacting accuracy in structural analyses.
Area of Science:
- Neuroimaging
- Radiology
- Biomedical Engineering
Background:
- Large-scale MRI studies often combine data from diverse imaging sequences.
- This heterogeneity can introduce variability, potentially leading to misinterpretations in structural analyses.
- Ensuring consistency across different acquisition parameters is crucial for reliable findings.
Purpose of the Study:
- To assess the consistency of structural brain measurements obtained using different MRI sequences, head coils, and scanners.
- To determine if pooled data from varying acquisition protocols can yield reliable results for neuroimaging research.
Main Methods:
- 163 participants (82 controls, 81 with autism spectrum disorder) underwent MRI scans.
- Scans were acquired using MPRAGE (12-channel coil, Siemens 3T Trio) and MP2RAGE (64-channel coil, Siemens 3T Prisma) sequences.
- FreeSurfer software was used for segmentation, and intraclass correlation coefficient (ICC) measured reproducibility.
Main Results:
- Total brain segmented volume showed high reproducibility (ICC = 0.99).
- Regional variability was noted, with the entorhinal cortex, frontal, and temporal poles showing the most volumetric variation.
- Surface area variability was highest in the insula and frontal/temporal poles; cortical thickness was most variable in the frontal and temporal poles.
Conclusions:
- MRI data acquired with different sequences (MPRAGE, MP2RAGE) and hardware are generally consistent for brain volume and surface area.
- Regional variations in accuracy may exist, particularly in specific anatomical areas.
- Cortical thickness measurements demonstrate higher overall variability across different acquisition settings.
