Detecting Primary Progressive Aphasia Atrophy Patterns: A Comparison of Visual Assessment and Quantitative Neuroimaging Techniques.

Background: There are now clinically available automated MRI analysis software programs that compare brain volumes of patients to a normative sample and provide -score data for various brain regions. These programs have yet to be validated in primary progressive aphasia (PPA).

Objective: To address this gap in the literature, we examined Neuroreader -scores in PPA, relative to visual MRI assessment. We predicted that Neuroreader 1) would be more sensitive for detecting left > right atrophy in the cortical lobar regions in logopenic variant PPA clinical phenotype (lvPPA), and 2) would distinguish lvPPA ( = 11) from amnestic mild cognitive impairment (aMCI;  = 12).

Methods: lvPPA or aMCI patients who underwent MRI with Neuroreader were included in this study. Two neuroradiologists rated 10 regions. Neuroreader lobar cores for those 10 regions, as well as a hippocampal asymmetry metric, were included in analyses.

Results: Cohen's Kappa coefficients were significant in 10 of the 28 computations ( = 0.351 to 0.593, ≤0.029). Neuroradiologists agreed 0% of the time that left asymmetry was present across regions. No significant differences emerged between aMCI and lvPPA in Neuroreader -scores across left or right frontal, temporal, or parietal regions (s > 0.10). There were significantly lower scores in the left compared to right for the hippocampus, as well as parietal, occipital, and temporal cortices in lvPPA.

Conclusion: Overall, our results indicated moderate to low interrater reliability, and raters never agreed that left asymmetry was present. While lower -scores in the left hemisphere regions emerged in lvPPA, Neuroreader failed to differentiate lvPPA from aMCI.