Chronic Traumatic Encephalopathy

KEY FACTS

TERMINOLOGY

• Definition

○ Neurodegenerative disease secondary to repetitive

concussive/subconcussive head injuries

• Synonyms

○ Dementia pugilistica ("punch-drunk")

○ Postconcussion syndrome

IMAGING

• MR

○ Age-inappropriate volume loss

– Voxel-based morphometry shows disproportionate

involvement of medial temporal lobes

○ Nonspecific T2/FLAIR punctate, confluent

hyperintensities in deep, periventricular white matter

(WM)

○ DTI shows loss of WM integrity

– Uncinate and superior/inferior longitudinal fasciculi

○ T2* shows microbleeds in ~ 10%

• PET

○ Temporoparietal hypometabolism on FDG-PET

○ PET imaging ligands for phosphorylated tau may be in

vivo biomarker

PATHOLOGY

• Etiology

○ Repetitive head trauma

○ Contact sports (football, soccer, hockey, boxing,

wrestling, mixed martial arts, etc.)

○ Battlefield exposure to blast waves generated by

improvised explosive devices

• Gross: Likened to octogenarian Alzheimer patient

• Microscopic: Neurofibrillary tangles, Aβ plaques

CLINICAL ISSUES

• Cognitive dysfunction, memory loss

• Variable mood, personality, behavior disorders

(Left) Axial FLAIR scan in a

middle-aged former

professional athlete with

early-onset dementia shows

diffuse bihemispheric volume

loss with extensive confluent

and punctate hyperintensities

in the subcortical and deep

cerebral white matter (WM).

(Right) Axial T2* SWI scan in

the same patient shows

numerous punctate

"blooming" foci in the

subcortical and deep WM ﬈,

consistent with microbleeds in

this case of clinically

diagnosed chronic traumatic

encephalopathy.

(Left) Autopsy in a patient

who survived a single episode

of severe head injury shows

remote effects of head

trauma. Note the bifrontal

encephalomalacia ﬇ and

extensive gliosis in the

subcortical WM ﬈. Note

absence of microbleeds.

(Right) Axial T2* GRE in an

elderly patient with a single

episode of moderate head

trauma shows left frontal

encephalomalacia and gliosis

﬈ with superficial siderosis of

the adjacent cortex ﬊. Note

the absence of microbleeds in

this case.

Brain: Pathology-Based Diagnoses: Malformations,

Trauma, and Stroke

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