A topic frequently addressed in this blog is the building body of evidence showing that the minority of patients who have long term, sometimes permanent, symptoms following concussion typically experience those symptoms because of injury to the brain, not to achieve some “secondary gain.” Although scientists do not have a clear understanding about why some people are more vulnerable to these injuries, we know as discussed in prior posts, that certain factors can play a role, such as genetics, prior head injuries and a history of migraines. Two recently published studies contribute to our understanding that real pathology likely underlies most persistent symptoms and that this pathology can be identified with advanced neuroimaging techniques. Read More
University of Toronto researchers have just published an important longitudinal study in the peer-reviewed Journal of Neurotrauma following patients with Post-Concussion Syndrome (PCS) based on a diagnosis of concussion in conformity with the international sport concussion criteria. This was the first longitudinal study that specifically excluded patients with contusions and hemorrhages identified by imaging (so-called “complicated” concussions), patients who tested positive on so-called “malingering” tests (the TOMM) and patients involved in litigation. Read More
In a study published in the Journal of the American Medical Association (JAMA) on December 20, 2016, Canadian researchers found that children and adolescents who returned to exercise within seven days of experiencing a concussion had nearly half the rate of persistent post-concussive symptoms a month later. This finding challenges the current cornerstone of pediatric concussion management, which is physical and cognitive rest until acute symptoms have resolved. Read More
In recent years a great deal of research has been done to identify an objective “biomarker” of concussion. As reported in this blog, some promise has been found in blood biomarkers (measuring plasma tau protein levels) and neuroimaging, such as the DTI MRI sequence. Unfortunately, these approaches are invasive and/or expensive and are not always a reliable indicator of concussion and concussion recovery. As reported in our November 27, 2016 blog post, until now, one of the most promising concussion screening tools was a series of vision tests endorsed by the Department of Defense.
Scientists at Northwestern University have now found a related, and what appears to be an even more precise and accurate tool, a measure of the brain’s electrophysiological response to sound. Read More
Department of Defense researchers endorse use of eye tests as an effective screening tool for acute mild traumatic brain injury (concussion)
In prior posts we have discussed the growing recognition that one of the signature symptoms of concussion is a subtle change in visual processing. Army researchers funded by the US Department of Defense have just published findings further supporting this understanding in the November 15, 2016 issue of the Journal of the Neurological Sciences.
In the published findings, the authors note that “mild” traumatic brain injury (mTBI) is sometimes difficult to diagnose because of the overlap of symptoms with other disorders such as PTSD. This has led to a quest for biomarkers or diagnostic tests (e.g. protein, imaging, cognitive, neurosensory.) This quest is especially significant for warfighters at risk for more severe “second-impact” concussions and whose lives and safety may be endangered by visual or cognitive compromises. Read More
Most experts in traumatic brain injury (TBI) agree that there is a high degree of variability in outcomes after TBI, including concussions (usually characterized as “mild” TBIs – mTBI.) In other words, this injury is heterogenous; generalizations about recovery rates and outcomes are not particularly productive.
In prior posts we have discussed research finding physical differences between patients who recover quickly and patients with persistent symptoms (such as differences in DTI imaging and differences in the presence of certain proteins.) This research contradicts the position some clinicians previously held that persistent symptoms following mTBI were likely the result of a “somatoform” or mental health disorder. We have also discussed research identifying some of the individual factors that explain the variability of outcomes, such as prior TBIs and preexisting migraine. We have also discussed how the particular forces involved in a TBI may affect different structures of the brain producing different outcomes (such as changes in vision, changes in balance or changes in the function of the pituitary gland resulting in hormonal imbalances.)
It has always been suspected that one of the factors explaining such variability in outcome may be genetic differences. Read More
There’s new evidence supporting immediate removal of athletes from play following concussion.
A new study published in the September, 2016 issue of Pediatrics provides evidence that returning to play immediately following a sports related concussion, even without a “second impact” nearly doubles, on average, the length of time required to recover and exposes athletes to a greater risk of protracted symptoms. As the authors point out in their report, the Institute of Medicine and National Research Council stated in 2013 that
“the culture of sports negatively influences SRC [sports related concussion] reporting and that athletes, coaches, and parents do not fully acknowledge the risks of playing while injured.”
In our May, 2014 post, we reported on research showing that traumatic brain injury, including mild traumatic brain injury (mTBI), can damage and cause dysfunction in the pituitary gland resulting in deficiencies in key hormones released by the pituitary gland, such as Growth Hormone (GH). As we explained in that post, the anatomy of the pituitary gland makes it particularly susceptible to the sheering injuries seen in TBI. These hormone deficiencies can produce many of the persistent symptoms seen following a TBI, such as fatigue, poor memory, depression, anxiety, emotional lability, exercise intolerance, lack of concentration and attention difficulties. (Although not always the case, these deficiencies can also produce physical symptoms, such as increased fat mass – especially in the abdominal area – and increased cholesterol.) We also noted findings showing that pituitary dysfunction can worsen over the five year period following an injury – in other words, that this is an issue that deserves to be monitored on an ongoing basis. Read More
Researchers at the University of Toronto have released the results of a study of the incidence of suicide in 236,000 concussion patients followed over a 20 year period. Read More
On January 16, 2016 the University of Pennsylvania announced the findings of a unique team studying concussion science, consisting of a professor of materials science and engineering and a professor of neurosurgery (also director of Penn Center for Brain Injury and Repair.) Read More
