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High correlations between MRI brain volume measurements based on NeuroQuant® and FreeSurfer
David E Ross1, Alfred L Ochs2, David F Tate3
1Virginia Institute of Neuropsychiatry, Midlothian, VA, USA; Department of Psychiatry, Virginia Commonwealth University, Richmond, VA, USA.
Transforming FreeSurfer (FS) brain volumes to NeuroQuant (NQ) volumes using linear regression significantly reduces effect size differences. Bayesian linear regression proved most effective, yielding trivially small effect sizes for improved MRI brain volume analysis.
Area of Science:
- Neuroimaging analysis
- Medical image processing
- Brain volume quantification
Background:
- NeuroQuant (NQ) and FreeSurfer (FS) are standard automated tools for MRI brain volume measurement.
- Previous studies noted high reliability but significant effect size discrepancies between NQ and FS.
- Large effect size differences can complicate comparative analyses and interpretations.
Purpose of the Study:
- To investigate the efficacy of linear transformations in reducing effect size differences between NQ and FS brain volume measurements.
- To develop and compare methods for transforming FreeSurfer volumes to be more comparable with NeuroQuant volumes.
- To enhance the reliability and comparability of automated brain volumetry data.
Main Methods:
- Utilized brain volume data from 60 subjects, including healthy controls and patients with neurological conditions (TBI, Alzheimer's disease).
- Applied two statistical approaches: traditional linear regression and Bayesian linear regression, to derive FS-to-NQ volume transformations.
- Performed regression analyses to establish linear transformation models for harmonizing FS and NQ measurements.
Main Results:
- Linear transformations using traditional linear regression reduced effect sizes to small or moderate levels.
- Bayesian linear regression-based transformations resulted in trivially small effect sizes, indicating high concordance.
- This study presents the first method for transforming FS to NQ data, achieving both high reliability and minimal effect size differences.
Conclusions:
- Linear transformations, particularly those employing Bayesian regression, are effective in reconciling discrepancies between NeuroQuant and FreeSurfer brain volume measurements.
- Bayesian regression offers a superior approach for harmonizing neuroimaging data, potentially improving the accuracy and consistency of brain volume analysis.
- The developed transformation method facilitates more reliable comparisons across studies and patient cohorts utilizing different automated volumetry software.
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