Brief Answer:
Read below

Detailed Answer:
I read your question carefully and I am sorry about what has happened to your wife.

Traumatic brain injury is a general term which includes many types of brain damage. So depending on the damaged site and its extent manifestations and permanent consequences will vary. It might have been useful if you could have uploaded some report with the findings of the brain imaging she had at the time.

Most common persisting symptoms are chronic headache, seizures, weakness of the limbs, fatigue, concentration and attention difficulties, memory issues, apathy, mood and behavioral changes. As I said symptoms and severity depends on location of brain lesions and their severity, not all symptoms are present in all patients.

Regarding treatment, there is no treatment to reverse the damage which has already happened to the brain tissue. So treatment is focused towards rehabilitation, physical therapy, speech therapy, occupational therapy, depending on the deficits which have remained. Medications are of use only for certain symptoms such as seizures which are treated with antiepileptics, or behavioral changes and aggression which may be treated with antipsychotics, depression with antidepressants and so on. When it comes to the memory issues you describe I am afraid there is no proven treatment for that purpose.

As for progression you shouldn't fear a progression of the symptoms, it is a one time event. Usually there is some improvement taking place during the first year thanks to brain plasticity, the process of the remaining nerve cells creating new connections. But that is a process taking place during the first year, 2 years at most. After 4 years she should be in a stable state, no reason to fear about progression (unless effects of aging are added on top over the years).

I realize my answer didn't offer many solution, that is the nature of the damage I am afraid. I hope it dealt with what you needed to know. I remain at your disposal for other questions.

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