This letter appeared in 'Dog World' newspaper in the Breed notes column on 5th September 2008

I live on the periphery of the Cavalier world but have spent the last 40 years involved in spinal pathology including the Chiari malformation and its association with syringomyelia and the MRI evaluation of these conditions. I have followed the issue of Chiari malformation and syringomyelia with some interest.

"In 2004, I addressed a meeting of the Cavalier breeders in Australia following the anxiety created by the research in the UK. I made the point at that time that there were multiple causes of syringomyelia the most common of which was trauma to the cervical spine. The recent BBC programme has raised a number of issues which I have been provoked into responding to:

1 The clinical research published is seriously flawed and the figures are simply unacceptable. The basis of any study such as this has to be developed from a sound population sample rather than a selected group, which will provide a massive bias rendering it from an epidemiological point of view useless. Unfortunately, this is not uncommon in scientific studies when the opinion of the researcher is clear almost before the study starts.

2 The finding of an anatomical abnormality such as the Chiari malformation is relatively common, at least in the human population, but the development of syringomyelia as a consequence of this is relatively uncommon.

3 There is no doubt that where syringomyelia is clearly defined, as with mitral valve disease, there should be no further breeding with that animal and probably some clinical screening of close relatives. I must make the point that syringomyelia is not just a diagnosis made by MRI but is a neurological syndrome with multiple features. Many with MRI abnormalities lead a very normal life.

4 As far as breeding is concerned it has yet to be determined the degree of penetrance in a genetic sense of the Chiari malformation and the subsequent development of syringomyelia. It remains the case of care, responsibility and further data regarding this with time.

5 The BBC programme is yet another example of the media encouraging a 'state of fear' knowing that there is little that the general population can do about extravagant and damaging claims. In this case, it is close to character assassination.

6 While in the UK in 2007, I was invited to examine a number of MRI images relating to this problem. There was one that was clearly diagnostic and it is my understanding that the breeder took responsible action. I also had the opportunity to view the MRI referred to in the BBC programme. I think the images were poor, inadequate and certainly not diagnostic anatomically.

There is no doubt that the problem has to be looked at seriously but in my view at least the evidence available does not support the propaganda and I refute a lot of what has been projected in the UK both academically and by the media.

I am delighted to have provoked some heated debate in the UK and am not the slightest bit offended by some of the comments from people who have little or no knowledge of their subject. By way of background I left Guy's Hospital in 1969 and since then have returned to the UK frequently working for short periods in major hospital units and being asked to talk at their meetings. Presumably they believe that even an Australian has something to contribute.

My interest in the Chiari malformation and the association with Syringomyelia goes back many years in the human and I have researched this with neurologists and neurosurgeons both at paediatric and adult level. My interest in the animal variation was really only provoked in the last five years by the claims being made in the UK.

I have discussed the issues with vets who agree that the basic principles regarding diagnosis and the progress to neurological damage would be the same as in humans. I would commend the article by Dominic J. Marino in the Winter Edition, 2007 of ‘The Royal Spaniels’ as an excellent summary of the current knowledge in this area. There are several important points which Dr Marino makes and I think should be emphasised -

1. The Chiari malformation is a developmental abnormality which in varying degrees is relatively common and may or may not be associated with the cerebellar structures descending into the cervical canal.

2. The concept that a blockage of cerebrospinal fluid at the base of the skull is the cause of a Syrinx continues to have problems and is yet to be clearly defined. New fluid dynamics studies may help in this regard in the near future.

3. The Chiari malformation does not equate to Syringomyelia which is a neurological condition caused by damage to the nervous tissue and screening programmes confined to MRI imaging should not presume a diagnosis of Syringomyelia. Trauma is probably the most common association with the development of a Syrinx and in many cases we simply cannot define a cause and under those circumstances should not label it.

4. Dr Marino emphasises the requirement for adequate MRI technology to image these abnormalities and even when assessing human cases with high class MRI equipment we may have difficulty in absolute diagnosis

I remain of the view that there is a genetic pre-determination for the Chiari malformation and that in absolutely clear cases breeding with those animals should not occur. Just how prevalent this is in the breed remains ‘sub judice’. It is very clear watching this debate at a distance that there are significant political issues clouding the picture and throwing abuse does little to rationalise it. There is a lot of defensive behaviour going on. At this point I am happy to drop out of the debate and let the process continue.