The following quote is from the above link.
“Traumatic brain injury (TBI) occurs from a sudden blow or jolt to the head. Brain injury often occurs during some type of trauma, such as an accident, blast, or a fall. Often when people refer to TBI, they are mistakenly talking about the symptoms that occur following a TBI. Actually, a TBI is the injury, not the symptoms.”
TBI is head injury and often visible at the time it occurs and afterwards. An estimated 80% of TBI injuries are mild and can be caused by a concussion. PTSD is an invisible wound that can occur following exposure to a traumatic event(s). PTSD symptoms can follow TBI. Both injuries, visible or not visible, require immediate and ongoing medical diagnosis and treatment. Although this is not a good news story and the website information is not fun reading, a high level of awareness is critical and increases the prospects of a positive outcome. Do not go with this alone! Listen to your loved ones and medical professionals.
Reconciliation: A Son’s Story