Table 1.
Neuropathology described as ‘characteristic’ of CTE in the literature
| Gross pathological features |
| Cavum septum pelluciduma |
| Lateral or third ventricle enlargementa |
| Frontal atrophy |
| Temporal atrophy |
| Diencephalon atrophy |
| Basal ganglia atrophy |
| Brainstem atrophy |
| Cerebellar atrophy |
| Thinning of the hypothalamic floor |
| Shrinkage of the mammillary bodiesa |
| Pallor of the substantia nigra |
| Hippocampal sclerosis |
| Reduced brain weight |
| Microscopic neuropathology |
| Amyloid-β deposition (variable) |
| Multifocal axonal varicosities |
| Frontal and temporal cortex |
| Subcortical white matter |
| Deep white matter tracts |
| Diffuse axonal loss |
| Subcortical white matter |
| White matter tracts |
| Neuronal loss |
| Hippocampus |
| Entorhinal cortex |
| Amygdala |
| Locus coeruleus |
| Substantia nigra |
| Medial thalamus |
| TDP-43 |
| Frontal cortex |
| Medial temporal cortexa |
| Hippocampusa |
| Amygdalaa |
| Insular cortices |
| Basal ganglia |
| Thalamus |
| Hypothalamus |
| Brainstem |
| Hyperphosphorylated tau |
| Perivascular in the neocortex |
| Depths of sulcib |
| Superficial layers of cerebral cortexa |
Supportive criteriaa and pathognomonic criterionb for CTE based on the preliminary consensus criteria (McKee et al., 2016). Prior to 2015, diverse and widespread non-specific neuropathology was described as ‘characteristic’ of CTE in some articles. Most of the neuropathology described in past articles is also present in association with ageing and in other neurological, neuropsychiatric, and neurodegenerative disorders—and is not unique to CTE. As of 2015, a small number of these are now considered preliminary asupportive criteria for the neuropathology of CTE, and a single finding, bp-tau in depths of sulci (neuronal and astrocytic), particularly in a perivascular distribution, is considered the sole necessary and sufficient pathognomonic criterion of CTE (McKee et al., 2016).