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Reproducibility of hippocampal atrophy rates measured with manual, FreeSurfer, AdaBoost, FSL/FIRST and the MAPS-HBSI methods in Alzheimer's disease. | LitMetric

AI Article Synopsis

  • The study evaluates the reproducibility of different algorithms used to measure hippocampal atrophy rates in Alzheimer's disease, comparing methods like FSL/FIRST and FreeSurfer among others.
  • Using MRI data from the ADNI study, researchers analyzed atrophy rates across 562 subjects at different MRI strengths, finding average rates of -1.1% for healthy controls, -3.0% for those mildly impaired, and -5.1% for Alzheimer's patients.
  • The MAPS-HBSI method showed the best reproducibility with significantly lower subject requirements for clinical trials compared to other methods, while all approaches maintained good accuracy against manual segmentation.

Article Abstract

The purpose of this study is to assess the reproducibility of hippocampal atrophy rate measurements of commonly used fully-automated algorithms in Alzheimer disease (AD). The reproducibility of hippocampal atrophy rate for FSL/FIRST, AdaBoost, FreeSurfer, MAPS independently and MAPS combined with the boundary shift integral (MAPS-HBSI) were calculated. Back-to-back (BTB) 3D T1-weighted MPRAGE MRI from the Alzheimer's Disease Neuroimaging Initiative (ADNI1) study at baseline and year one were used. Analysis on 3 groups of subjects was performed - 562 subjects at 1.5T, a 75 subject group that also had manual segmentation and 111 subjects at 3T. A simple and novel statistical test based on the binomial distribution was used that handled outlying data points robustly. Median hippocampal atrophy rates were -1.1%/year for healthy controls, -3.0%/year for mildly cognitively impaired and -5.1%/year for AD subjects. The best reproducibility was observed for MAPS-HBSI (1.3%), while the other methods tested had reproducibilities at least 50% higher at 1.5T and 3T which was statistically significant. For a clinical trial, MAPS-HBSI should require less than half the subjects of the other methods tested. All methods had good accuracy versus manual segmentation. The MAPS-HBSI method has substantially better reproducibility than the other methods considered.

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Source
http://dx.doi.org/10.1016/j.pscychresns.2016.04.006DOI Listing

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