Chronic Traumatic Encephalopathy (CTE) is considered to be a progressive neurodegenerative syndrome, developed after a person experiences repetitive blows to the head comprising symptomatic concussions and asymptomatic sub concussive blows persisting over a period of years or decades; it is mainly found in athletes involved in contact sports such as boxers, football players and sometimes even military veterans. CTE is a very rare condition and its diagnosis can be made only by autopsy where different sections of the brain can be studied. It has been known since 1920s as a disorder associated with boxing and was formerly called dementia pugilistic or punch drunken syndrome.
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The brain gradually deteriorates and eventually over years ends up losing mass in individuals with CTE. Some parts of the brain show an abnormal buildup of tau protein whose function is to stabilize the neuron structure, this causes major disturbance in neuron functioning. Certain parts of the brain get atrophied while others enlarged. These changes begin several months, years or sometimes decades after the person’s last brain trauma. Common symptoms are memory loss, impaired judgment, difficulty with balance and motor skills, impulsive or erratic behavior, emotional instability, depression or apathy, vision and focusing problems, gradual onset of dementia etc.
People with CTE might be wrongly diagnosed as the symptoms are similar to those of Alzheimer’s and Parkinson’s. CTE was first diagnosed in a professional football player in the year 2002. CTE has so far been diagnosed only by post mortem analysis of the brain tissue when an individual is suspected to have suffered from it. Pathologists having knowledge of brain diseases slice the brain in thin slices (allowing light to pass through) after removing it from the skull and preserving in formalin solution. These slices are washed with special chemicals that stain the tau clumps (present in a unique pattern in CTE) reddish brown making them visible under the microscope, confirming the diagnosis of CTE in the person. CTE diagnosis is not a part of natural autopsy and takes several months to be finished.
A new method has been developed by researchers at Icahn School of Medicine in New York to diagnose CTE while the patient is still alive; the method involves injection of chemicals that can reach the brain followed by sending the patient into a brain scanner which helps detect the abnormalities. Since CTE is an incurable disease, its diagnosis is of high importance. People have committed suicide under the notion of having CTE and later autopsy reports were negative for CTE. This diagnostic test was conducted only on one retired NFL player (still alive), so how good it is, is hard to say.