The same cortico-efferent tract involvement in progressive bulbar palsy and in ‘classical’ ALS: A tract of interest-based MRI study

Universität Ulm

 

Abstract


Objective

The study was designed to investigate specific white matter alterations in diffusion tensor imaging (DTI) data from PBP patients using a hypothesis-guided tract-of-interest-based approach (compared with ‘classical’ ALS patients and controls) to identify in vivo microstructural changes according to the neuropathologically defined ALS-related corticoefferent tract pathology.

Methods
DTI-based white matter mapping was performed both by an unbiased voxel-wise statistical comparison and by a hypothesis-guided tract-wise analysis of fractional anisotropy (FA) maps according to the ALS-staging pattern for 23 PBP and 23 ALS patients vs 23 matched controls.

Results
The analysis of white matter integrity demonstrated regional FA reductions along the CST and also in frontal and prefrontal brain areas both in PBP patients and ALS patients with additional regional FA reduction in the pons of the PBP group. In the tract-specific analysis according to the neuropathological ALS-staging pattern, PBP and ALS patients showed identical significant alterations of ALS-related tract systems when compared with controls.

Conclusions
The DTI study including the tract-of-interest-based analysis showed the same microstructural corticoefferent involvement patterns in PBP patients as in ALS, which supports the hypothesis that PBP is a phenotypical variant of ALS.

 

HP. Müller, M. Gorges, K. Del Tredici, A. C. Ludolph & J. Kassubek: The same cortico-efferent tract involvement in progressive bulbar palsy and in ‘classical’ ALS: A tract of interest-based MRI study. NeuroImage: Clinical 24 (2019)