Brain injuries can be classified into various types based on their cause, mechanism, and severity.

Acquired Brain Injury

Acquired brain injuries are caused by changes or problems with the brain itself. These problems can occur for many reasons.

Some examples of these brain injuries are:

  • Anoxia / Hypoxia – Occurs when the brain is either totally deprived of oxygen or deprived of sufficient oxygen. Examples include near drowning, asphyxiation, exposure to toxins, illegal drug use, alcohol abuse, and carbon monoxide poisoning.
  • Tumors – A tumor in the brain may cause injury to the surrounding brain tissue. Neurosurgical removal of the tumor is usually performed. The surgical process may result in changes to the brain.
  • Stroke or “Cerebrovascular Accident (CVA)” – A sudden and often severe impairment of the body brought on by a disruption in the flow of blood to the brain. When the blood fails to get through to parts of the brain, the oxygen supply to those areas is cut off, and the affected brain cells die. If blood flow is interrupted by a blockage in a blood vessel in the brain or neck, an ischemic stroke can occur. A hemorrhagic stroke, often called a brain bleed, is when a blood vessel in the brain ruptures or leaks, with subsequent bleeding into the surrounding tissue.
  • Infectious, Toxic, or Metabolic Disorders – There are many types of infectious, toxic, and metabolic changes (chemical or biological reactions) in the body that can affect brain functioning. For example, a virus may attack the brain, causing injury to the brain tissue. An overdose of drugs or a sudden chemical change because of the failure of a body organ are examples of metabolic changes that can injure brain tissue.

Traumatic Brain Injury

Traumatic brain injury (TBI) refers to an acquired brain injury in which an external blow to the head has caused damage to the brain.

  • Open Head Injury – An open head injury is a visible assault to the head that may result from a gunshot wound, shrapnel, an accident, or an object going through the skull into the brain. This type of injury is more likely to damage a specific area of the brain.
  • Closed Head Injury – A closed head injury occurs when there is a blow to the head, such as in a motor vehicle crash or fall. In this case, the skull hits a stationary object and the brain, which is suspended in cerebral spinal fluid inside the skull, may bounce back and forth inside the skull, causing damage to the brain where it comes in contact with the skull. The brain may also turn on its axis (the brain stem), causing localized (focal) or widespread (diffuse) damage.

    Closed head injuries are the most common type of brain injury, often causing both focal and diffuse damage at the same time. Diffuse brain trauma can occur when the nerve fibers throughout the brain stem and into the brain are stretched or distorted. A concussion or a blast injury may cause brain injury.

    Terms used to describe closed head injury include:

    • Contusions are injuries that bruise a portion of the brain.
    • Concussion literally means “to be shaken violently.” It is usually caused by a blow to the head by an external force. Concussions may cause a temporary loss of consciousness. There does not have to be any loss of consciousness to sustain a concussion. A concussion may also result in an alteration of mental state (i.e. being confused or dazed). A concussion may cause a mild brain injury.
    • Coup-contrecoup describes contusions that are both at the site of the impact and on the complete opposite side of the brain. This occurs when the force impacting the head is not only great enough to cause a contusion at the site of impact, but also is able to move the brain and cause it to slam into the opposite side of the skull, which causes the additional contusion.

Secondary Damage to the Brain

The brain can sustain further injury when the brain swells inside the skull. Fluid accumulates, causing pressure to increase and impinge on delicate brain tissue. Delayed bleeding from damaged blood vessels can similarly injure the brain. Preventing secondary damage is the primary medical challenge during the initial period following brain injury.

The information provided on this website is intended for general informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. If you believe you may have sustained a brain injury or are experiencing a medical emergency, please contact a qualified healthcare professional or seek immediate medical attention.

  • So Many People, So Little Information

    As an individual with a brain injury, or a family member or friend of an individual with a brain injury, you probably have never experienced what you are now going through. You may feel overwhelmed. You may never have heard the terms brain injury or traumatic brain injury. You may not know what questions to ask.

    Often, medical staff are focused primarily on ensuring optimal care for you, your family member, or friend. As a result, they don’t always keep you informed of what is happening. In reality, they may not yet have any specific answers. Information regarding survival and quality of life generally doesn’t become clear for at least 48–72 hours post injury when swelling in the brain begins to subside. Even then, information may be incomplete.

    Start keeping a journal. Write down your thoughts, feelings, observations, and questions as you think of them. This way, you can be sure to remember to ask all your questions and make sure they are answered. Write down the answers you receive, so that you can look back at them later. The journal can also help you see the progress of the healing process over time. Sometimes, when you are in the middle of a situation, it is difficult to see improvements. A journal can assist you in seeing these changes.

  • Resources

    The first few days or weeks following a diagnosis of brain injury can be confusing and even frightening. These resources will help answer some of your questions and ease your concerns. The following resources provide basic information for families dealing with the medical treatment of brain injury, including definitions of medical concepts and professionals.

    Model Systems Knowledge Translation Center

    The MSKTC works closely with researchers in the 16 Traumatic Brain Injury (TBI) Model Systems to develop resources for people living with traumatic brain injuries and their supporters.

     MSKTC Website

    Brainline

    BrainLine is a national multimedia project offering authoritative information and support to anyone whose life has been affected by brain injury or PTSD: people with brain injuries, their family and friends, and the professionals who work with them.

     Brainline Website

    U.S. Centers for Disease Control and Prevention

    A traumatic brain injury, or TBI, is an injury that affects how the brain works. TBI is a major cause of death and disability in the United States. Check out the CDC website resources pertaining to TBI.

     CDC Website

  • Professionals Who Might Be Involved

    It often seems like many doctors and others are running in and out, and it is hard to keep track of everything and everyone. You should get the names of all doctors involved. Find out their names, their medical specialty, their phone number and the best time to reach them. You also can ask doctors when they would expect to visit again. To get complete information, talk to every doctor. Be willing to ask for clarification of any information you do not understand.

    Intensivist

    Physician who specializes in treating and managing a critically ill or injured individual in an Intensive Care Unit.

    Neurosurgeon

    Physician trained to care for all types of brain problems and perform brain surgery as needed.

    Neurologist

    Physician who specializes in the nervous system and its disorders.

    Neuropsychologist

    Specialist who evaluates the cognitive (or thinking) functions of the individual following brain injury. Neuropsychologists generally are involved in the treatment process further down the road, after the individual has stabilized.

    Physiatrist

    Physician specializing in physical medicine and the rehabilitation process. A physiatrist may also coordinate the rehabilitation team.

    Plastic Surgeon

    Surgeon who repairs or replaces malformed, injured, or lost tissues. This physician performs cosmetic surgery to correct physical defects as a result of injury.

    Family physician

    If in the area, can sometimes act as a liaison to the family and provide the family with needed information in a more personal manner.

    Physical Therapist, Occupational Therapist, Speech Therapist

    Professionals involved in the rehabilitation process after the individual has been medically stabilized.

    Other staff that you might want to identify

    Emergency Room or Hospital Social Worker Patient Liaison (Patient Care Representative) Nurses/Head Nurse or Nursing Supervisor Chaplain

    Individuals and families need a liaison who can explain and help advocate for the individual with the injury. Often, the best sources of information are the floor nurses. Try to “connect” with the nurse who is involved with you and your family member or friend. Hospital social workers can also help increase the flow of communication.