Brain Imaging in Boxing
Cavum Septum Pellucidum
Computerized axial scanning has revolutionized the practice of medicine, in particular the study of the brain and brain diseases over the last 30 years.
The CAT scan and MRI scan are used on a routine daily basis by neurologists and neurosurgeons in the diagnosis of brain disease and brain injury. Naturally this technology has also been applied to boxing.
In this talk I would like to deal with the following subjects:
Brief outline of scanning technique;
Background literature on cavum septum pellucidum;
Personal series of 22 boxers;
Case of Boxer X
Theory of cavum septum pellucidum;
Significance of cavum septum pellucidum;
Place of scanning in boxing.
The traditional x-ray takes a simple “snap shot” of the skull which is recorded on film.
Tomographic scanning uses a large complex machine which rotates around the body or head shooting hundreds of x-rays, taking thousands of readings at each level.
A computer analyses this massive data and reconstructs a visual image of the body at each level.
CAT scan uses x-rays and the MRI scan uses a powerful magnet to induce molecular resonance in the body tissue and this is then picked up by special sensors and again reassembled by the computer in the same way as with the CAT scan and the pictures in fact look fairly similar.
In this talk I will be dealing with the use of scanning in long-term boxing safety and surveillance of fighters, not its use in acute boxing brain injuries. In boxers who have suffered acute injuries the scan and in particular the CAT scan is vital in rapidly diagnosing the nature of the injury or the need for surgery and this is self-evident and will not be discussed in this talk.
As a neurologist my main interest is the prevention of long-term brain damage or the “punch drunk” syndrome
Pathological studies of boxer’s brains over the past 40 years in particular those of Spillane (1962), Maudsley and
Ferguson (1963) and Corsellis (1973) showed that damage to the septum pellucidum was a frequent and constant feature in punch drunk subjects.
The septum pellucidum is a thin midline structure actually consisting 2 fused layers which separate the lateral ventricles of the brain anteriorly.
There is no definite function assigned to this structure which may be largely vestigial, like the appendix.
In boxers who have suffered long term damage this membrane is often perforated or ruptured or more commonly the 2 leaves of the membrane become separated (as they were in embryonic development) leaving a cavity or cave inside which is called the cavum septum pellucidum.
It should be emphasized that a small proportion of normal people have this variation and the incidence in the normal population is somewhere between 1 – 5 %.
However the 3 studies mentioned, showed high incidence of damage to the septum pellucidum in boxers who had had very prolonged careers..
Dr. P. McCrory of the Sports Medicine Research Institute in
Melbourne published a review article on the Cavum Septum Pellucidum
And as the title indicates the author was skeptical about the value of this observation in assessing the fitness of boxers to continue participating.
With this background therefore I would like to present the findings of a series of scans of 22 elite South African boxers who I saw for medical evaluation prior to them going to fight overseas. Most of the boxers were destined to compete in the
United Kingdom but some also
Europe and all the local boxing jurisdictions required a CAT scan as well as other blood tests including HIV and Hepatitis.
As mentioned of these were elite boxers and 12 of the 22 were either World Champions or going to fight for World titles. All had had CAT scan or MRI scans and for the purpose of this study, I examined these scans for the presence of a cavum septum pellucidum.
Five of the boxers had a definite cavum septum pellucidum, five had equivocal or minor changes and 12 were clearly normal with no separation of the septum.
When I analyzed the results further and compare the boxers who had a definite cavum there is clear evidence that a cavum is an indication of a long career in boxing, and having probably absorbed a great deal of punishment.
One of boxers was a particular cause for concern. A scan in 2003 had been completely normal but when I saw him again in 2004 he had lost his previous 2 bouts and his World Title and had in fact suffered fairly severe punishment. I did not see the bouts myself but was advised of this.
The conclusion was unavoidable that he had developed cystic dilatation of the occipital horn of the right lateral ventricle. This could only have been a consequence of the 2 losses he had sustained. In view of this, I could not condone him for boxing in the
UK and I am certain that the British Board would have felt the same.
Based on this presentation I would like to suggest that the damage or separation of the septum pellucidum with the formation of the cavum is caused by pressure waves developing in the cerebro spinal fluid especially with lateral rotation. These cause perforation of the thin septum and in extreme cases actual destruction of the septum and the separation or the formation of the cavum is part of this process.
Similarly the cystic occipital horn I presented in the boxer is probably caused by the same mechanism.
Furthermore there is a rare neurological condition called syringomyelia where a cystic dilation occurs in the upper spinal cord and this has been thought to be due to the formation of pressure waves in the cerebro spinal fluid forcing open the central canal of the spinal cord by similar mechanism and this is known as the “Gardner’s hypothesis”.
What therefore is the significance of cavum septum pellucidum picked up on a scan in a boxer?
Firstly it must be said that the cavum is no indication of a clinical abnormality or brain damage. Some almost certainly occurred due to incidental trauma, perhaps while as an amateur and some may even be normal variations. I therefore would agree completely with Professor McCrory that there is no reason to automatically ban a boxer who has a Cavum Septum Pellucidum on scanning.
However the figures which I have presented show a strong trend towards an association of the cavum with excessive punishment.
My view is therefore that a cavum septum should be taken into account in evaluating a boxer’s fitness to continue boxing, particularly in the case of a mature boxer. If it is correlates with age, excessive punishment or other negative factors and particularly if it can be shown to have developed or progressed, it would be, in my view, an indication to terminate a boxer’s career, in his interests.
In conclusion what is the place of brain scanning in the medical surveillance of boxers?
This is an expensive technology. In
South Africa the cost would be approximately $300 – $400 American and an MRI scan perhaps 50% more. This is way above what junior boxers, certainly in
South Africa, could afford.
Nevertheless, ideally every boxer should have a scan at the outset of his career. Perhaps the odd vascular malformation would be found or some other congenital abnormality. Although these cases are likely to be rare, the scan would be a useful baseline for comparison later in his career.
I touched briefly on the important part in assessing acute brain trauma and this is obvious and a separate issue.
I believe it is appropriate as a precaution in elite boxers boxing at international and world level and this formed the basis of the cases I saw in this series, which I presented. It is obviously important to the supervising authority in a foreign for indemnity reasons. I recall many years ago seeing a boxer from
USA with a dubious record, who we rejected on the grounds of a large Cavum.
Evaluation of boxers late in their career is, I believe, an important function for brain imaging. This would be where the supervising authorities have reason to be concerned about a boxer’s performance and general fitness.