Table 4.

CTE pathological stages

Stages	Descriptions
1	Discrete perivascular p-tau foci in the neocortex, usually found at the depths of sulci
2	Multiple perivascular p-tau foci in the neocortex, typically at the depths of the cerebral sulci, with involvement of superficial layers of adjacent cortex and sparing of the medial temporal lobe structures
3	Widespread p-tau lesions in the frontal, temporal, parietal, insular, and septal neocortices, most severe at the depths of the sulci and in the superficial cortical layers, with involvement of the entorhinal cortex, amygdala, and hippocampus
4	Diffuse pathology throughout the cerebral cortex and the medial temporal structures, sparing the calcarine cortex

Abbreviation: CTE chronic traumatic encephalopathy, p-tau phosphorylated tau

CTE pathological stages are based on extent and anatomic distribution of p-tau pathology [2]