Abstract
On Tuesday 14 March 2017, a meeting was held at the Royal Society of Medicine (RSM), organised by the psychiatry section of the RSM in association with the Medico-Legal Society.
The topic was “Mild traumatic brain injury: diagnostic, clinical and legal controversies.”
Speakers included Prof Michael Swash, neurologist; Prof David Sharp, neurologist; guest speaker Dr Grant Iverson, Prof of physical medicine; Dr Michael Gross, neurologist; Dr Nigel Walton, neuropsychologist; Prof Steve Gentleman, neuropathologist; and Augustus Ullstein QC, barrister and judge. The morning was chaired by Prof Malcolm Weller, neuropsychiatrist and in the afternoon by Dr Martin Skelton-Robinson, neuropsychologist. The legal aspect was introduced by Dr David Sumner, Prof of neuropathology.
The full day meeting, which was set up by Prof Malcolm Weller, was well attended attracting some 200 participants from a range of disciplines including anaesthetics, psychiatry, neuropsychology, nursing, radiology, sports medicine as well as solicitors and barristers.
“Mild traumatic brain injury” (MTBI) is a bit of a misnomer. It largely means that the injury did not kill the person, that there is no grossly evident wound and it is mainly linked to the effects of rapid acceleration, deceleration or rotation of the brain inside an intact skull. The first speaker, Prof Swash, pointed out some of the vagueness and variations in definition of the immediate effects. These may include transient loss of consciousness, amnesia and confusion, being lumped together under the term “concussion”. As the speakers progressed, it became increasingly apparent that looking for gross evidence of injury is immensely over simplistic, particularly in the light of our slowly growing knowledge of the complexity and subtlety of brain function. It seems likely that at least some of the effects are more widespread and occur at what might be described as a microscopic level affecting neuronal function, possibly synaptic (nerve cell to nerve cell). Our modern methods of looking at brain structure are beginning to show just how amazing this is with 3D pictures of vascular supply and white matter as well as fMRIs giving us a few more clues about which bits of brain are involved in particular tasks. Unfortunately, these make it even more apparent how crude our current knowledge is.
A different aspect presented by speakers, particularly the guest speaker Dr Iverson from Boston, USA, was that not only is there a great variation in the effects comparing one individual with another but that previous experience and social environment make a huge difference in terms of vulnerability and persistence of symptoms. A significant proportion of people, it seems, appear to recover but have ongoing measurable differences in function.
A third aspect presented was the import of all of this in day-to-day functioning particularly in relation to legal proceedings. Neuropsychology can look at or at least describe some of the effects and speculate on the mechanisms involved and disrupted. However, again, it was pointed out that our knowledge is very primitive and we need to be as careful as possible both in testing cerebral function and in being aware of the limitations of current tests used. A lawyer’s view of evaluating damage to brain function was fascinating. For example, emphasis on presentation of symptoms may be described as malingering, but may also be a genuine wish on the part of the subject to convey to others the seriousness of what has happened to them.
We could have benefited from a little more information about such things as sensitivity and specificity of tests used in evaluating effects and also perhaps the way in which many diagnostic categories, such as concussion, are “Operational Definitions”, in other words, simply descriptions of symptom clusters which do not indicate a particular or even unified underlying mechanism. However, overall the meeting was very informative, challenging and provoked healthy argument. It is to be hoped that it will not remain a one-off and at the very least become an annual event.
Readers might like to suggest some possible themes for the next Conference.