Diffusion Tensor Imaging (DTI): An Advanced Tool In Detecting Traumatic Brain Injury

Diffusion Tensor Imaging (DTI): An Advanced Tool In Detecting Traumatic Brain Injury If you have ever been in an accident or had a significant injury, your doctor probably recommended that you go the hospital to have an MRI. You probably went to the hospital, laid on a table on your back, and were placed inside a narrow tunnel which made you feel claustrophobic. While many of us are probably familiar with this test and have had one at some point during our lives, most are not aware that a relatively new technology exists which might be able to detect injuries not visible on a standard MRI. This new technology is known as diffuser tensor imaging, or DTI. What exactly is Diffuser Tensor Imaging? Diffuser Tensor Imaging, or DTI, is an imaging technique which is used to identify the unique directional movement of molecules, especially water molecules, along muscle and neural tracts. One of its uses is to identify the linkages and structures of white matter tracts in the brain.[1] You may be asking yourself, what exactly is white matter and why would a doctor want to see its structure? According to BioMedCentral, you could refer to white matter as the subway of the brain – connecting different regions of grey matter in the cerebrum to one another. Imagine living in a city and having to walk from one area to another 5 miles away; transport makes this much more fluent and helps make your tasks easier. This is pretty much the same for your brain.[2] The white matter acts as a transport device, and is vital to the normal function of a healthy brain. However, just as a real subway can get damaged, collapse, or stop working, so can the white matter in your brain. Brain injuries, especially violent blows to the head, can cause such an issue. While a regular MRI may be able to scan the brain and show tissue which appears to be abnormal, DTI can provide a doctor with a 3D scan of the white matter tracts to pinpoint where exactly the issue lies. That sort of specificity and accuracy does not exist when it comes to a standard MRI. What makes DTI different (and more effective) than a standard MRI? DTI is more complicated than MRI in terms of data analysis [3] DTI will show injuries which a standard MRI will not, as explained by Dr. Benson in the case of Ruppel v. Kucanin, “Brain injuries are classified as either focal or diffuse. A focal injury is a localized injury, such as that caused by a stroke, a direct blow to the head, or an aneurysm, and is typically a contusion on the surface of the brain, visible by conventional scanning (MRI). On the other hand, a diffuse axonal injury involves scattered damage to the brain substance, particularly the white matter that is comprised of axon fibers. A closed head (non-penetrating) brain injury, the most common type of traumatic brain injury, can include focal injury, diffuse injury, or both. A brain injury can include only evidence of diffuse axonal injury when it is a result of “relatively little direct impact to the skull such as during a motor vehicular collision with a restrained passenger and little or no impact to the head.” Diffuse axonal injury is the hallmark pathology in closed head injury and is not visible on conventional MRI imaging in milder cases. Diffuse axonal injury results from acceleration or deceleration of the head (skull) which causes deformations (stretch and strain) of the brain substance leading to shear injury of white matter fibers. A traditional MRI shows the structure of the brain, and the majority of people with mild brain injury will have a normal MRI even if they have significant impairment. DTI is a more sensitive, three-dimensional type of MRI that examines the microstructure of the white matter in the brain. DTI can show reduction in fractional anisotrophy (“FA”) meaning that the white matter in the brain has been damaged.”[4] As you can tell, it is quite complicated, but essentially, if the white matter in your brain has been damaged, you have a better chance of locating and diagnosing such an injury with DTI than you would with an MRI. What legal challenges does this new technology face? While this technology may be doing wonders for the medical community, the legal community hasn't exactly embraced the new technology with open arms. To understand why, it is important to have some background knowledge of the Daubert Standard. The Daubert Standard is used by a court to make a preliminary assessment of whether an expert's scientific testimony is based on reasoning or methodology that is scientifically valid.[5] If a doctor's testing and methodology are going to be used during a trial, Daubert explains the factors that are to be considered in determining whether the methodology is valid. Those factors are: (1) whether the theory or technique in question can be and has been tested; (2) whether it has been subjected to peer review and publication; (3) its known or potential error rate; (4) the existence and maintenance of standards controlling its operation; and (5) whether it has attracted widespread acceptance within a relevant scientific community.[6] Courts have struggled with whether or not DTI satisfies each of those requirements, and whether or not its results should be used in court. Many say that this new technology cannot be relied upon because it has not been widely accepted within the medical community, and because it cannot be tested to ensure accuracy. However, numerous courts which have examined DTI technology have determined that it is reliable and should be admitted.  In Ruppel v. Kucanin, a United States District Court case out of Indiana, the court explained that when it comes to DTI technology, “The evidence shows that while DTI is a relatively new technology, it is gaining general acceptance... there have been numerous validation studies, published in peer reviewed journals, on the use of DTI to detect…injuries.”[7] The same court went on to say later in that same case that “there are many articles published in peer-reviewed publications that cover the effectiveness of DTI in detecting mild TBI (Traumatic Brain Injury).” In fact, as of early 2010, there were 3,472 papers on DTI published in peer review journals.[8] As it pertains to the error rate of DTI's, it has been shown that the error rate is not nearly as high as that associated with an MRI. Another factor which enhances this new technology's reliability is the fact that it was approved by the Food and Drug Administration, or FDA. In Hammar v. Sentinel Ins. Co., the court noted that DTI is “FDA approved, peer reviewed and approved, and a commercially marketed modality which has been in clinical use for the evaluation of suspected head traumas including mild traumatic brain injury.”[9] So what is the main takeaway from courts as to whether or not this new technology should be relied upon? I believe that the Ruppel court said it best when they noted that, “While DTI is a relatively new and developing technology, it is well on its way to gaining general acceptance in the scientific community as a tool for identifying mild TBI.” St. Petersburg Personal Injury Attorney Recovering from a person injury can be a long and sometimes stressful process. When you find yourself in this position, you need to work with a person injury attorney who you can trust will get the job done. To work with an experienced attorney who will zealously fight for you and handle your claim with the dedication and attention to detail it requires, contact Dolman Law Group Accident Injury Lawyers, PA at (727) 451-6900 to schedule your legal consultation with a member of our firm today. We are here to answer any questions you have about the personal injury claim process and help you seek the monetary compensation you deserve. Dolman Law Group Accident Injury Lawyers, PA 800 North Belcher Road Clearwater, FL 3375 (727) 451-6900 References: [1] https://medical-dictionary.thefreedictionary.com/diffusion+tensor+imaging [2] https://blogs.biomedcentral.com/on-biology/2014/03/14/the-subway-of-the-brain-why-white-matter-matters/ [3] NINDS - Press Releases [4] Ruppel v. Kucanin, 2011 WL 2470621 [5] https://www.law.cornell.edu/wex/daubert_standard [6] https://www.law.cornell.edu/wex/daubert_standard [7] Ruppel v. Kucanin, 2011 WL 2470621 [8] Ruppel v. Kucanin, 2011 WL 2470621 [9] Hammar v. Sentinel Ins. Co., Ltd., No. 08–019984 at *2 (Fla.Cir.Ct.2010)