Functional Magnetic Resonance Imaging For Brain Injuries
Traumatic brain injury is an exceptionally common and potentially devastating problem. Studies have estimated that nearly 1.6 million head injuries occur in the United States each year, resulting in over 50,000 deaths and over 70,000 patients with permanent neurological discrepancies. TBI accounts for up to 10% of the health care budget and an estimated annual cost of $30 billion to society. As such, quick proper management of TBI sequelae can significantly alter their course, especially within 48 hours of the injury, neuroimaging techniques—which can determine the presence and extent of the injury and guide surgical planning and minimally invasive interventions—play important roles in the acute therapy of TBI. Imaging also can be important in the chronic therapy of TBI, identifying chronic sequelae, determining prognosis and guiding rehabilitation [1]. This form of distinctive analysis of the brain is essential among the varying degrees of TBIs. These injuries are among the most frightening and serious injuries commonly associated with automobile, motorcycle, trucking and sports-related accidents.
Brain Mapping: Functional MRI
Neuroimaging techniques are becoming increasingly useful in the study of TBI; whereas in CTs and standard MRIs, structural images can readily demonstrate large focal contusions or bleeds, diffuse axonal injury may be detected indirectly by brain volume loss (volumetric analysis) and/or the use of diffusion tensor imaging (DTI) aids in discovery. DTI studies have shown reductions in fractional anisotropy (FA) at sites of traumatic axonal shearing injury, corresponding to a loss of microstructural fiber integrity, resulting in the reduced directionality of microscopic water motion [2]. These are only some of the imaging techniques that have been used in correlation with the Glasgow Coma Scale score or other clinical measures of TBI severity to determine brain injury and extent. However, a newer more distinctive MRI called functional MRI, is a noninvasive diagnostic test that measures small changes in blood flow as a person performs tasks while in the MRI scanner, contributing to the understanding of the functional aspects of the brain.
Mayfield Brain & Spine describes functional MRI as a technique that detects the brain in action when we are speaking, moving or doing any other activity. It has an advantage over other imaging studies that focus only on the structure of the brain. This test helps doctors understand how a tumor or a stroke has altered brain function. It is also an important tool in planning surgery—called brain mapping—that helps surgeons remove tumors to the greatest extent possible without harming areas that are critical to a patient's quality of life. Back tracking signals caused by the increase in blood flow to specific areas of the brain, functional MRIs can detect the difference in such a signal that is produced when we start thinking. By thinking, neurons in the brain use more oxygen and demand more blood. The MRI scanner measures this signal difference and displays the activity as a colored area. This measure of the tiny metabolic changes that take place in an active part of the brain help doctors navigate the proper pathways when not only differentiating the damage of a brain injury but also help to prevent possible damage when surgical means are necessitated. Due to the precise and safe nature of the test, fMRI is becoming the diagnostic of choice for learning how a normal, diseased or injured brain is working, as well as assessing the potential risks of surgery or other invasive treatments of the brain.
FMRI Study of Patients with Severe Brain Injury
After a TBI, patients are left with lasting effects that are continuously being studied. After a severe brain injury, some unfortunate patients are left in a state of wakefulness with their eyes wide open, but without any indication of awareness. This “vegetative state” is a part of severe brain injury study and analysis as doctors try to establish a connection to a victim. There are some patients who are fortunate enough to show inconsistent signs of awareness but still cannot communicate effectively and are said to be in a “minimally conscious state.” The differential diagnosis of disorders of consciousness is challenging. The rate of misdiagnosis is approximately 40%, and new methods are required to complement bedside testing, particularly if the patient's capacity to show behavioral signs of awareness is diminished.
The researchers studied 54 patients with severe brain injury, 23 in the vegetative state and 31 in a minimally conscious state. After verifying their fMRI methods on 16 healthy brains, the brain-injured patients were asked to perform a motor task, such as imagining playing tennis, as well as a spatial imagery task, such as imagining navigating the streets of their city or walking from room to room in their house. The authors examined the fMRI images to see of areas of the brain lit up to indicate if the motor or spatial imagery were activated in these patients appropriately during these tasks when compared to the brain activity of a health person. Of the 54 patients, 5 were able to willfully modulate their brain activity with activation of the supplementary motor area during the tennis task (5 out of 5) and activation of the parahippocampal gyrus (4 out of 5) during the spatial navigation task. All 5 of these patients has a TBI and 4 out of 5 had been previously classified as being in a vegetative state. After this test, 3 were reclassified as being in a minimally conscious state; while the other 2 had no signs of physical awareness despite the fMRI findings [3].
Interestingly enough, 1 of the patients was found to adapt to the fMRI as a means of communication. When the authors asked the patient autobiological questions such as (“Is your name Fred?”), the patient was able to imagine a “yes” through a motor task and a “no” through a sensory task. By this measure, examination of the fMRI areas of activation could be used to gauge the patient's answers, which are found to be autobiographically correct. In this specific example, there were no other ways of forming a connection of communication other than through the imaging technique.
Not only did this study show the potential for fMRI to bridge the dissociation that can occur between behavior that is readily observable during a standard clinical assessment and the actual level of residual cognitive function after serious brain injury but it also showed that at least in one patient with severe impairment of consciousness, fMRI established the patient's ability to communicate solely by modulating brain activity whereas this ability could not be established at the bedside. With further development, this technique can be used by some patients to express their thoughts, control their environment, and increase their quality of life [4].
Dolman Law Group Accident Injury Lawyers, PA
The evolution of technology in brain imaging is continuing to distinguish brain injuries, brain mapping and with further development, establish a line of communication. This progress in studying the brain and its functionality is a part of an area of study that is never truly concrete because of the complexity of the brain. The brain is a fascinating part of the human body that is essential for people to lead a normal and healthy lifestyle. However, it is important to note that if you or a loved one has suffered a traumatic brain injury or closed head injury as a result of the negligence exhibited by an individual or corporation, it is necessary to retain an attorney experienced in handling brain injury claims. These accidents may take a major toll on a person's life because of the location and severity of an injury. More often than not, these injuries have costly medical bills and create other losses that should be compensated for. Call the experienced attorneys at the Dolman Law Group Accident Injury Lawyers, PA for help in your claim today. We are here to help you in your time of need. Our number is (727) 451-6900.
Dolman Law Group Accident Injury Lawyers, PA
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Clearwater, FL 33765
(727) 451-6900
References:
[1] Neuroimaging in Traumatic Brain Imaging
[2] Advances in neuroimaging of traumatic brain injury and posttraumatic stress disorder
[3] Brain mapping: functional MRI and DTI
[4] https://www.medscape.com/viewarticle/719105