Studies over the last several years have shown that the lymphatic system serving the brain, located in the membranes covering the brain (the “meninges”) plays an important role in brain injury recovery.
As most people know, the lymphatic system helps to rid the body of toxins and waste, including the byproducts of the body’s immune response to injury. For brain injury this is sometimes described as “damage/danger-associated molecular patterns” – “DAMPs” – such as protein aggregates, necrotic cells, and cellular debris.
Researchers at the University of Virginia, at the Center for Brain Immunology and Glia, have released an important study furthering our understanding of the role meningeal lymphatic dysfunction plays in causing some patients to suffer severe and long-lasting impairments following even a “mild” traumatic brain injury (TBI) and helps to explain why these injuries increase the risk for neurodegenerative problems such as Alzheimer’s, ALS and dementia. Read More
American Academy of Neurology publishes an important study showing consistent evidence of axonal injury following a single TBI for years after injury using multiple measures, including a blood biomarker, MRI/DTI and volumetric analysis, and functional tests
An article published in April, 2020 by the American College of Emergency Physicians reports on evidence that underdiagnosis of Mild Traumatic Brain Injury (mTBI) “is a pervasive problem in the emergency setting,” and that even patients who receive a diagnosis are unlikely to receive appropriate discharge education and are therefore at risk of missing opportunities for treatment, referral and improvement in outcomes. Koval et. at., Concussion Care in the Emergency Department: A Prospective Operational Brief Report, Annals of Emergency Medicine 2020 Apr;75(4):483-490. Read More
In 2015, Dr. John Leddy and his groundbreaking concussion team at the University of Buffalo published a peer reviewed article cautioning that symptoms after head injury, including cognitive symptoms, that have traditionally been ascribed to brain injury can originate, at least in part, from injury to the neck, He counseled that the cervical spine should be examined and, if injured, should be treated to address these symptoms. “Brain or strain? Symptoms alone do not distinguish physiologic concussion from cervical/vestibular injury.”
A review of the literature published not long after the Leddy article, in the Journal of Sports Medicine, sounded a similar theme. “Cervical Spine Involvement in Mild Traumatic Brain Injury: A Review.” It noted that many post-concussion symptoms can be explained by injuries to structures near or in the head, other than the brain itself. “For example,” the authors note, “following a trauma, structures such as the cervical spine, the vestibular ocular system and the temporomandibular joint can be injured.” They note, for example, that “neck pain, headaches, dizziness and balance dysfunction are common symptoms associated with both mTBI and WAD” (cervical spine injury.) Addressing neck injuries, they suggest, may lead to better concussion recovery. A randomized controlled trial testing this hypothesis is currently in process. Read More
In prior posts I have discussed the growing evidence that traumatic brain injuries, even so-called “mild” traumatic brain injuries (mTBI), can lead to neuroendocrine dysfunction (NED) – most commonly growth hormone (GH) deficiency due to pituitary dysfunction. Although growth hormone deficiency often results in physical symptoms such as loss of lean muscle mass and strength, increased body fat around the waist, and dyslipidemia, other common GH deficiency symptoms overlap with the symptoms of “persistent post-concussion”- such as fatigue, poor memory, anxiety, depression, emotional lability, poor attention and poor concentration.
My earliest post on this issue discussed the August 2012 Department of Defense (DOD) clinical recommendations for screening for neuroendocrine dysfunction in “mild” traumatic brain injury (“mTBI”) cases – where indicative symptoms persist for more than three month or appear within three years. The guidelines contemplated a simple blood test, but subsequent studies, also discussed in this blog, showed that the only reliable means of detecting GH deficiency is provocative testing, which is expensive and takes several hours (the guidelines do suggest further assessment by an endocrinologist, even where the screening test is negative, if symptoms of NED persist.) Read More
I have discussed research on the important role of sleep in TBI recovery in prior posts. Accordingly, I have encouraged clients to get help with sleep issues as soon as they become apparent after an injury. Studies have shown that approximately 50% of patients diagnosed with mTBI (“mild traumatic brain injury”) experience chronic sleep disruption. There is evidence that the brain repairs itself during sleep, which is one of the reasons why poor sleep can delay recovery. Poor sleep following a brain injury has been associated with disturbance in the normal rhythm of melatonin production.
A recent double-blind, placebo-controlled study by researchers at the University of Arizona, published in Neurobiology of Disease 134 (2020) 104579 (funded by the US Army Medical Research and Development Command ) demonstrated that morning exposure to blue wavelength light improves sleep quality and leads to measurable cognitive improvements and positive changes in brain anatomy and function as measured by functional and structural MRIs. Read More
In a recent review the literature, researchers at the Walter Reed Army Institute of Research identified the establishment of a protective gut microbiota as a “compelling therapeutic avenue” for the treatment of traumatic brain injury (TBI).
In a January 23, 2018 post this author summarized evidence that a TBI can trigger pathology in the Gut-Brain Axis and increase infections. The Walter Reed researchers dive deeper into this issue. Summarizing the research, they explain that “brain injury induces disruptions in the composition of the gut microbiota, i.e. gut dysbiosis, which has been shown to contribute to TBI-related neuropathology and impaired behavioral outcomes.” (emphasis added.) Read More
Post Traumatic Stress Disorder (PTSD) and Traumatic Brain Injury (TBI) have been often been viewed as two distinct conditions, one with an “emotional” cause and the other with a “physical” cause. It has been recognized for some time that these conditions can produce similar symptoms, such as problems with sleep, concentration, memory and mood. As noted by the authors of a literature review published in Current Neurology and Neuroscience Reports, “increasingly symptoms previously presumed to be specific to PTSD or TBI are being identified in both disorders.” These include symptoms more commonly associated with TBI such as headache, dizziness, balance and vision problems. Evidence has also demonstrated that patients with a history of TBI are more likely to meet criteria for PTSD than others with similar intensity injuries and that patients who are also diagnosed with PTSD are significantly more likely to report persistent cognitive or sensory problems after a TBI. Read More
As discussed in prior posts, the most common symptom of post-concussion syndrome (PCS) is post-traumatic headache accompanied by photophobia (heightened sensitivity to light.) These symptoms can interfere with both work and activities of daily living. The Canadian Journal of Neurological Sciences recently reviewed the literature to determine the current level of knowledge concerning the pathophysiology, the underlying mechanisms, producing these symptoms.
Understanding these mechanisms is key to providing more effective care. The paper notes, based on the literature review, that headache occurs in up to 88% of sports-related concussions, followed closely and concomitantly by photophobia. Approximately 8-35% of post traumatic headaches will “chronicize” (become a long-term problem.) Read More
In prior posts I have discussed the growing understanding in the scientific community that vision is often disrupted in subtle ways following a concussion (both the ability of the eyes to track and higher level visual processing). I noted that the introduction to a recent issue of the respected journal NeuroRehabilitation was devoted entirely to vision disturbance following TBI.
