At Miller & Zois we frequently handle personal injury cases involving all types of traumatic brain injuries. Whether they result from a car or truck accident, or medical malpractice, brain injuries are always very serious.
DAI falls under the category of diffuse brain injury. A diffuse brain injury involves brain damage that occurs over a wide area instead of one specific location. The term "axonal" refers to the axons (nerve fibers) that are connected to neurons in the brain. Axons are critical to brain function as they are the primary transmission of electrical impulses that control almost every system in the body. When the axons are damaged in some way, it disrupts the transmission of those electrical signals, which can limit or completely restrict the brain's overall functioning.
Brain injuries are either focal or diffuse. Focal is a localized injury, often a contusion on the surface of the brain. Usually, a blow to the head is the source of a focal injury. Diffuse axonal injury is the hallmark pathology in closed head injury and is not visible on conventional MRI imaging in less severe cases.
A diffuse axonal injury is the consequence of acceleration or deceleration of the head. This causes deformations of the brain substance leading to shear injury of the brain's delicate white matter. Many head injuries are both focal and diffuse axonal injury.
A diffuse axonal injury (DAI) occurs when the connective nerve fibers (axons) in the brain are sheared or torn when the brain bounces around inside the skull during a traumatic impact. A diffuse axonal injury is one of the most serious and deadly types of traumatic brain injuries resulting in damage to numerous parts of the brain. DAI injury frequently results in a coma or persistent vegetative state. Approximately 25% of diffuse axonal brain injuries lead to death. Our lawyers see these types of cases more commonly in truck accidents than car accidents because the force of the impact the rotation of the victim is typically much greater.
DAI usually develops after some type of trauma to the head, but the damage is not actually from the physical trauma itself. The axonal injury comes as a result of the brain rapidly shifting back and forth in the skull from acceleration or deceleration. Rotational acceleration has been shown to contribute more than 80% to brain strain in motor vehicle accidents. When the brain is moving too much in the skull, the axons in the neurons become disrupted.
The movement causes the brain tissue to slide over other tissue and result in what's called a shearing injury. The shearing makes lesions on the brain, meaning the tissue has become abnormal, damaged, or inflamed. If the tissue is damaged, brain cells die, which causes the brain to become even more swollen. The pressure can decrease blood flow to the brain and therefore increase the amount of brain damage or cause a stroke.
Some common traumas that can cause a diffuse axonal injury include
Diffuse axonal injuries are separated into three different grades. This is referred to as The Adams classification. This classification is based on the severity and locations of the brain damage from injury.
- Grade 1: This is the mildest form of DAI. It's characterized by microscopic changes in the white matter of the cerebral cortex, corpus callosum, brain stem, and cerebellum
- Grade 2: This is considered a moderate form of DAI. In this grade, there are grossly evident focal lesions isolated to the corpus callosum.
- Grade 3: This is the most severe form of DAI. With grade 3, there are additional focal lesions on the brainstem.
The primary symptom for most people with DAI is loss of consciousness. Depending on how severe the damage is, this can last for six or more hours. People with minor DAI may remain conscious after the injury but will still experience other symptoms of brain damage. The symptoms of DAI can vary widely since each injury is unique and different parts of the brain can be affected. Some common signs of brain damage include
- Disorientation or confusion
- Throbbing headache
- Nausea and vomiting
- Difficulty sleeping or sleeping longer than usual
- Lack of balance and coordination
A more severe diffuse axonal injury can cause a prolonged coma that varies in duration based on the severity and extent of the lesions (Bain 2000). Injury due to a high-speed collision, coma, and early death are hallmarks often present in individuals who present with DAI. These are just really awful injuries. Our lawyers have had very tragic cases where the victim who suffered a severe diffuse axonal brain injury remains unconscious or severely disabled until death.
Diagnosing a DAI can be difficult since most patients with this condition are unconscious and cannot provide the doctor with information about how the injury occurred or what symptoms they are experiencing. ( Doctors usually rely on certain tests to determine whether a person has a DAI.
- Magnetic Resonance Imaging (MRI): This is the most preferred method of testing for DAI. The machine uses magnets, radio waves, and a computer screen to show a detailed image of the brain.
- CT Scan: Somewhat similar to an MRI, this test involves using an x-ray machine and a computer screen to make a detailed image of the brain. CT scans can be less reliable than an MRI, as it can sometimes result in false negatives, so additional tests are often used to confirm the diagnosis.
- Evoked Potentials: This test is also referred to as the SSEP, BAER, and VEP. It tests and analyzes the visual, auditory, and sensory pathways in their brain to see how the brain is functioning.
- Electroencephalogram (EEG): This is a test that can measure the amount of electrical activity occurring in the brain.
Diffuse axonal injuries require immediate treatment to help prevent any additional damage to the brain. Often the first step in the process is taking measures to reduce swelling inside the brain. Steroids or other anti-inflammatory drugs are used to mitigate inflammation. Unfortunately, there is no surgery available that can fix a DAI as it's nearly impossible to re-connect disrupted nerve fibers and restore dead brain cells. If the person has sustained a minor or moderate axonal injury, they will need to go through intense rehabilitation once they have regained consciousness and their condition has stabilized. The prognosis for these patients is obviously much better than a patient with a Grade 3 injury.
Rehabilitation for DAI usually involves a multidisciplinary team of doctors that can create an individualized recovery plan that works to address the patient's specific needs. This team is made up of doctors, brain injury specialists, nurses, counselors, and physical and occupational therapists. The goal of treatment is to try and restore as much brain function as possible to help the patient return to a normal life. It can take months or even years for treatment to be completed. Rehabilitation treatments often include
- Speech therapy
- Physical therapy
- Occupational therapy
- Recreational therapy
- Adaptive equipment training
For severe cases of DAI, the prognosis is bleak. The victim may not be able to recover. Many people with this condition stay in a coma or vegetative-like state. If they do regain consciousness, they are often left with long-term complications.
Once someone suffers from a DAI, it cannot ever be truly "cured" because there is no way to restore dead brain cells or nerve fiber connections. People with this condition will most likely deal with lingering complications for the rest of their life. As far as whether the condition is "reversible", there is no clear cut answer.
Each case of DAI is different, and recovery depends on different factors, such as the severity of the damage, location of the damage, and which symptoms are present. People with minor axonal injuries may be able to recover from some of the damage or at least mitigate complications associated with the injury. Severe cases of DAI most likely will not improve, especially if the person has fallen into a coma for an extended period.
The prognosis for diffuse axonal injuries is generally poor. Many people are not able to survive a severe head injury. About 90% of survivors from DAI will remain unconscious or in a vegetative-like state. For the 10% that do become conscious again, most will experience severe and permanent impairments. In the case of very minor DAI, full recovery is possible for a small number of people.
Diffuse axonal injury (sometimes called a "shearing" injury) occurs when the brain is violently thrust forward and backward impacting the inside of skull cavity. This occurs when the head rapidly accelerates and/or decelerates in response to an external force such as whiplash in a vehicle collision. Direct impact on the head not necessary for DAI to occur. High-impact car accidents are by far the most frequent cause of diffuse axonal brain injuries. But diffuse axonal injury can also be caused by blunt force impacts to the head in a fall, assault or other accident.
The pathophysiology of a diffuse brain injury is an insult to the brain, usually rotational, that causes a breakdown of neuron interconnection. Most victims have neurological deficits that impact the brain white matter and brainstem. As we talk about above, studies show the number of lesions in the white matter tracts is correlated to the severity of the injury.
We talk about all of the symptoms above but the most common symptom is the least specific: a headache.
Brain imaging tests, such as MRI or CT scans. Acute brain damage that has occurred in the immediate past does not typically show up on this type of scan. However, imaging tests conducted several months down the line may indicate the atrophy or loss of some brain matter.
Below is a summary of the underlying facts in recent verdicts and reported settlements from cases involving a diffuse axonal brain injury. These should be used for informational purposes only as all cases are unique and the compensation varies wildly for seemly similar cases. Still, getting some idea of what the payouts can look like in these cases helps victims, their families, and lawyers better understand the settlement value of these cases.
Plaintiff v Defendant Property Manager (New York 2018) $3 million: The plaintiff, an 28-year old marketing associate, was hit in the head by a heavy ceiling tile that fell from the ceiling of an office building. Initially, his head injury appeared to be minor but it was later found that he suffered diffuse axonal shearing. The injury left him with permanent cognitive disabilities preventing him from working.
Clarke v Austin (New York 2017) $50,000: The defendant driver hit an 8-year old pedestrian with his vehicle at a busy intersection. The impact caused the boy to suffer diffuse axonal brain injury of moderate severity. The case settled for $50,000. Why so little? This is another case where an awful claim was limited because of the defendant's inadequate insurance policy (and insufficient uninsured motorist coverage).
KD Pro Ami v State Farm (California 2017) $125,000: Plaintiff (13 years old) was crossing the street on his skateboard when he was run over at low speed by the defendant - a teenage driver making a left turn. The plaintiff suffered diffuse axonal injury and was unconscious for an extended period. He also fractured his hip and lost several teeth. The case settled for full policy limits of $125,000. (This award certainly seems light, right?.)
Moore v State of California (California 2017) $59.2 million: The primary plaintiff was a 20-year old road excavation worker who was run over at a highway job site. He suffered severe diffuse axonal brain injury leaving him in a permanent vegetative state. He sued the California Department of Transportation (CDOT) for negligently failing to control traffic and ensure safety at the road work site. His co-worker who nearly got hit and witnessed the event also sued for emotional distress. A jury in Humbolt County found CDOT 100% liable and awarded $59.2 million in damages.
Rogers v Major (New York 2014) $100,000: The plaintiff, a 22-year old college student, was walking across city intersection when he was hit by the defendant in his car. Plaintiff suffered a diffuse axonal injury resulting in significant mental impairment. The case settled for policy limits. Obviously, this is a case worth millions but low insurance policies often trump justice.
Chadiez v Garfara Transport (California 2012) $1 million: Plaintiff lost control of her car on a highway and after coming to a stop she was rear-ended by the defendant driving a large tractor trailer truck. Plaintiff suffered a diffuse axonal injury with intracranial hemorrhaging. She also fractured several ribs. The case settled for the truck company's policy limits.
Neidinger v American Mutual Ins. (Wisconsin 2010) $1.1 million: Plaintiff was jogging on a sidewalk when she was hit from behind by a 2000 Chevy Impala. The impact caused scattered diffuse axonal injury to her brain. She also suffered an AC shoulder tear, dislocated knee, and other injuries. The case was settled after a pre-trial settlement conference.
Scrodin v Redwood Fire & Casualty Co (California 2010) $1 million: Plaintiff, 48-year old small business owner, was sideswiped on the highway causing his car to roll over numerous times. Plaintiff ended up with fractured ribs, a fractured shoulder and diffuse axonal brain damage leaving him with permanent memory loss, total loss of smell and taste and other cognitive problems.
Weimer v Classen (Washington 2008) $500,000: Plaintiff, a 29-year old construction worker, was riding his motorcycle when a left-turning transport van struck him. He suffered a diffuse axonal brain injury and was in a coma for over a month before he eventually died. The case settled for policy limits of $500,000.
Dahl v Joussett (New Jersey 2007) $595,000: Plaintiff, a 19-year-old student, was stopped at a red light when she was rear ended by a drunk driver. She suffered diffuse axonal brain damage which left her with speech difficulties and balance problems. She also had back injuries and a fractured hip.
If you or a family member suffered a diffuse axonal brain injury (or another type of brain injury) in an accident that was caused by someone else's negligence, contact Miller & Zois. Cases involving brain injuries are more complicated than other types of personal injury cases. You need lawyers who are experienced and understand the science of brain injuries. The brain injury attorneys at Miller & Zois can help you investigate your case and find out if you may be entitled to compensation. If you have a brain injury case and want an experienced firm who can take the case to trial, call 800-553-8082 or get a free online consultation here.Supporting Axonal Brain Injury Literature
- Izzy S, et. al: Revisiting Grade 3 Diffuse Axonal Injury: Not All Brainstem Microbleeds are Prognostically Equal. Neurocrit Care. 2017 Oct;27(2):199-207 (Glasgow Coma Scale very correlated to prognosis).
- Vieira R, et. al: Diffuse Axonal Injury: Epidemiology, Outcome and Associated Risk Factors. Front Neurol. 2016;7:178 (The prognosis of patients after suffering a DAI is correlated to the number of lesions identified through imaging with 48 hours of admission).
- Zhang J, et. al: Brain strains in vehicle impact tests. Annu Proc Assoc Adv Automot Med. 2006; 50:1-12 (rotational accelerations, as we say above, contribute to more than 80% of the brain strains in car accidents) and, as a result, should be quantified for improved injury assessment).
- Anderson R, et.al: Impact mechanics and axonal injury in a sheep model. J Neurotrauma. 2003;20(10):961-974.
- Adams J, et al: Diffuse axonal injury due to nonmissile head injury in humans: an analysis of 45 cases. Ann Neurol. 1982 Dec;12(6):557-63.