Our findings are an extension of the application of the DTI-based in vivo neuropathological staging to restricted ALS phenotypes with the demonstration of corticofugal tract involvement according to the established TDP-43 propagation scheme, as previously performed in progressive lower motor neuron disease [15, 16], PLS [17, 18], and progressive bulbar palsy [19]. The gene discussed is TARDBP; the disease is progressive bulbar palsy.