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
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
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 2003 CDC sent a report to Congress on “mild” traumatic brain injuries. (MTBI, also sometimes called “concussion.”) The report cautioned that, contrary to past understanding, “mild” brain injuries can cause serious, permanent problems:
“In recent decades, public health and health care communities have become increasingly aware that the consequences of mild traumatic brain injury (MTBI) may not, in fact, be mild. Epidemiologic research has identified MTBI as a public health problem of large magnitude, while clinical research has provided evidence that these injuries can cause serious, lasting problems.”
A new study published in the Journal of the American Medical Association adds to a growing body of evidence pointing to traumatic brain injuries, of all levels of severity, as an important risk factor for suicide.
The significance of the study is discussed in an opinion in the same issue of JAMA. Both the increased risk of suicide and the prevalence of depression following TBI have been discussed in prior posts in this blog. Read More
Although males represent a majority of emergency department visits for sports and recreation-related concussion, researchers have recently found that female athletes have a higher rate of concussion and appear to have worse outcomes than their male counterparts participating in the same sport. University of Pennsylvania researchers have recently identified anatomical differences between male and female axons that may explain this increased vulnerability. Read More
Canadian researchers assessed 236 individuals diagnosed with traumatic brain injury at 4, 8 and 12 months following injury. The results confirm prior studies showing that depression in very prevalent following TBI. Read More
As discussed in prior posts on this blog, sleep alterations are commonly found after a concussion or other traumatic brain injury, both short term and in some cases long term. One of the most well documented impacts of concussion, also discussed in prior posts, is an increased risk of mood disturbances, including depression, increased anxiety and increased risk of suicide. In recent years researchers have turned to sleep studies to explore the connection between these symptoms.
There is substantial evidence in the literature of the role healthy sleep plays in the “consolidation” of emotional memories. At first blush, this research is counter-intuitive. If sleep “consolidates” emotional memories, doesn’t this have the potential to increase rather than decrease mood disturbance? The answer appears to be that, although sleep preserves memory of events associated with emotional experience, at the same time it weakens the emotional “charge” coating the experience (referred to in the literature as “valence”) in a process called “habituation.” As one researcher hypothesized, “we sleep to forget the emotional tone, yet sleep to remember the tagged information.”Read More
A review published in the September 2017 issue of Frontiers in Neurology proposes use of “systems science” to better understand concussion diagnosis and prognosis. This is a discipline that analyzes complex problems as whole systems and integrates research findings from different disciplines. In explaining the need for a systems approach, the reviewers note one description of concussion that is uniformly recognized – that it is a highly heterogeneous phenomenon, with numerous factors interacting dynamically to influence an individual’s recovery trajectory. (This concept is highlighted in the title of one of the Concussion WebCasts made available by the American Association of Family Physicians : “If you have seen one concussion, you have seen one concussion.”) Read More
