Not as catchy, is it? I have read with interest lately in so many places people referring to cm as their brain being too big. It is the title of blogs, t-shirts and newspaper articles "Woman facing delicate surgery because brain too big for skull 11-04-2007" is the title of a recent news article about Julie Carter http://www.myplainview.com/site/news.cfm?newsid=18988358&BRD=517&PAG=461&dept_id While I get the fact that for some of us this is a humourous way to state the problem and is meant tongue and cheek, I worry that this is sending the wrong message.
I guess I am especially conscious of this as my herniation is 0mm. For reference your cerebellum should sit 3-5mm above the foramen to allow for free flow of CSF thru the foramen magnum and mine is right at the foramen when laying down for my MRI. I have all the most common symptoms of chiari including the classic sub-occipital headache, swallowing issues, blurred and double vision, inner ear issues including vertigo, tinnitus and increased hearing sensitivity, numbness to my face and tongue, heart arrhthymias, pseudotumor cerebri etc, etc, etc. How can I have all these symptoms and only have chiari with a 0mm herniation you might ask? Well all my NS up here in Canada so far say you can't. Period. end of story. Not willing to entertain the idea at all or look at any of the new research being done.
The reason why I can have all the symptoms of chiari and have a 0mm herniation, I believe, lies within the posterior fossa. We need to look at what is actually CAUSING chiari to get to the bottom of this. The most recent research tells us that cm is a skull base abnormality meaning during fetal development when your skull base was forming something did not form as it should. The posterior fossa was underdeveloped or too small and there is often other skull base abnormalities that go along with cm b/c they were all forming at the same time. Things like retroflexed odontoid and abnormalities of the cervical spine.
The problem wasn't that your brain over grew it was that you skull under-developed. This under-developed posterior fossa (the back part of your skull) is too small and because of this fact your brain has no choice but to herniate downward thru the foramen in an effort to find enough space to be. As Dr. Bolognese so elequently puts it " the box is too small for the contents". Dr. Milhorat expains the concept in great detail in his study Chiari Redefined. In this study 364 symptomatic patients were examined and a full 9% of patients had herniation less than 5mm with no differences in the number or severity of symptoms. As well 57% of this sub-group also had syringomyelia illustrating the disruption in CSF flow that can occur even with minimal herniations. All patients also had evidence of hind-brain over-crowding. Dr. Milhorat states "These observations indicate that the extent of tonsillar herniation cannot be used as the sole criteria for the diagnosis of cm"
Using a imaginary line drawn to diagnose cm without any weight given to clinical symptoms or presence of syringomyelia is in my opinion, nonsensical. We are allowing radiologists who are unaware of any of our symptoms and have never met us, diagose us (or not diagnose us) with a serious disorder. It goes against all common sense. I have all of the most common symptoms of cm, I have evidence of CSF disruption (syringomyelia) I have a small posterior fossa and I have symptoms of pseudotumor cerebri stemming from a blockage in free flow of my CSF. In my mind this is over-whelming evidence that I have cm and that the current wide spread practice of diagnosing by a line drawn on your MRI is outdated.
I want to say that I am not upset or angered by anyone that chooses to use that terminology, I just think that maybe it is time to watch what message we are sending. We are all responsible for increasing awareness. Until such time as a celebrity wants to take up the torch for us, it falls to all of us to educate the public-and our doctors-about what cm is and what it isn't. I think getting the correct message out there is essential to all of us getting the care we need. Please see the following link for more information about the mounting evidence illustrating this fact http://www3.sympatico.ca/ejfs/chiari0pubs.html I believe there are thousands of people with minimal herniations out there suffering needlessly because there symptoms are being discounted and mis-diagnosed as mine were. I luckily persisted and got answers from the Chiari Institute but many do not have the funds or opportunity to do the same. Let me know what you all think? Is it time for some new slogans?
(Note: I am not a doctor or an expert, these are just my opinions and perspective on this issue)