Chronic Traumatic Encephalopathy
- Chronic Traumatic Encephalopathy (CTE)
- Chronic traumatic encephalopathy is a progressive degenerative brain disorder that can occur in people with recurrent head trauma.
- Chronic Traumatic Encephalopathy is most commonly found in recurrent mild traumatic brain injury including athletes who participate in contact sports, such as football, boxing, and hockey. It is also common in military personnel. 
- Exact pathophysiology is unknown, however believed to be due to Tau protein and beta-amyloid accumulation in the brain. 
- Tau protein in the brain aggregates into neurofibrillary tangles (NFTs) which lead to disruption of normal neuronal function and cell death.
- Beta-amyloid (Aβ) is a protein that forms plaques in the brain and is the hall-mark of Alzheimers disease. In CTE, accelerated Aβ deposition is believed to contribute to play in role in neuronal degeneration. 
- In several studies, individuals with CTE were found to have elevated inflammatory markers in their central nervous system (CNS). 
- Repetitive head trauma 
- Early exposure to head trauma 
- Advanced age
- Genetic predisposition 
- Alzheimer's disease
- Parkinson's disease
- Frontotemporal dementia
- Other traumatic injury related dementia disorders 
- In-depth characterization of symptoms and duration
- History of head injuries
- Sports history
- Military service history
- Neurological and psychiatric history
- Family history of dementia
- Smoking, alcohol use and other risk factors
- Complete neurological examination
- Assess limb movement for rigidity
- Assess for gait disturbances
- Look out for tremor and poor coordination
- To date, there is no special test that is proven to be sensitive or specific in diagnosing CTE
- There is currently no specific clinical syndrome, neuroimaging finding or biomarker that has been shown to reliably diagnose CTE.
- Postmortem evaluation may show tau-immunoreactive degenerative changes in the superficial cortical layers, a finding that is specific for CTE.   
In addition to a comprehensive clinical assessment, the initial evaluation of chronic traumatic encephalopathy may include:
- Neuropsychological testing
- Neuroimaging may be helpful to exclude other potential causes of cognitive decline
- To date, there is no known cure for CTE. Management is supportive and targeted towards mitigating symptoms and improving quality of life.
- Pharmacological interventions:
- Antidepressants: Selective Serotonin Reuptake Inhibitors (SSRIs) may be helpful to improve mood and depressive symptoms. 
- Cognitive enhancers: drugs such as donepezil or memantine, which are typically used to treat Alzheimer's disease, may be used to address cognitive deficits in CTE, although the data on their effectiveness is scarce. 
- Antipsychotic medications: may be used for severe behavioral disturbances, aggressive behavior, or psychosis, although should be used with caution due to their side effect profile.
- Cognitive Behavioral Therapy (CBT): is a form of psychotherapy that focuses on identifying cognitive deficits, negative thoughts and behavioral patterns, and helps patients develop coping strategies to tackle them. May be helpful for CTE patients experiencing memory loss, depression, anxiety, or psychosis. 
- Physical therapy: especially helpful with patients experiencing motor disturbances such as Parkinsonism or frequent falls.
- Supportive care: educating patients about CTE and ensuring that they have adequate support at home as well as the presence of appropriate safety protocols to prevent head injuries.
- To date, there is no known operative intervention that is proven to be effective in managing CTE.
Rehab and Return to Play
Rehabilitation Return to Play/Work
Prognosis and Complications
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- Stein TD et al. Beta-amyloid deposition in chronic traumatic encephalopathy. Acta Neuropathol. 2015;130(1):21-34. doi:10.1007/s00401-015-1435-9.
- Cherry JD et al. CCL11 is increased in the CNS in chronic traumatic encephalopathy but not in Alzheimer's disease. PLoS One. 2017;12(9):e0185541. doi:10.1371/journal.pone.0185541.
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