OK, I have this relative with this condition, and to save her some bucks, I’ve opted to do this operation myself, and would like to know where best to cut, and how deep.
Just kidding, obviously, about the amateur surgery, but here’s the question:
I had never heard of the condition before, and some quick Googling turned up pretty much what she had said in her email.
But what’s the deal with the “syrinx?” I understand what it is, based on her message and the same quick research, but I don’t get the etymology of how this cerebrospinal cyst acquired the name of a pan flute.
PS: I’m reasonably certain this thread has the highest words-I-don’t-understand-to-words-I-do-understand ratio of any I’ve ever encountered on the SDMB. Mazel tov!
Apparently, the “syrinx” part refers to a cavity created in the spinal cord because the herniated bit of brain prevents proper circulation of the cerebrospinal fluid.
I’m double confused by this. First, because syrinx in animals refers to the voice box of birds. Secondly, because I thought that cerebrospinal fluid was produced by the choroid plexus in the brain and then traveled down through the spinal cord via the fourth ventricle. I’m not sure why a blockage at the foramen magnum would cause a distal dilation of the spinal cord. Maybe there is spinal fluid production within the cord itself in humans?
There isn’t. Humans only have choroid plexus in the ventricles.
I don’t really see how the syrinx forms due to the herniation. Maybe when the cerebellum herniates, it blocks the superior subarachnoid space, and as a result, the entire volume of CSF has to flow down into the inferior space, around the spine, and back up to the arachnoid villi to be reabsorbed. If so, then the syrinx would be analogous to the ventricular expansion you get during normal pressure hydrocephalus.
I don’t know, though. I looked at my medical textbooks, and this wasn’t there. In fact, I saw an article that said that there’s still quite a bit of controversy as to the etiology of the symptoms associated with Arnold-Chiari malformation.
Apparently, this condition is fairly cryptic, with diagnosis rates only on the rise recently with advanced use of MRI.
How can having your cerebellum through your foramen magnum be cryptic? I thought that was the primary cause of death with hydrocephalus, what with the crushing of the breathing, walking, and other generally important centers.
That’s what I was taught too - tonsilar herniation is Bad Juju. But then again, so many are asymptomatic throughout their lives, and only get diagnosed when they come in complaining of a bit of a headache…
I have a Chiari malformation, but mine is not particularly large, and has never caused me any noticable trouble.
The only reason I know it exists at all is because several family members have them, and when I had an MRI for a completely unrelated issue, my doctor checked for Chiari basically just out of curiosity.
As I understand it, more common use of the MRI has lead to the discovery that the percentage of people in the population with Chiari malformations is significantly higher then was originally predicted. But it’s really all about degree and severity… now days, the majority of patients with a known Chiari malformation are “subclinical” having no significant medical problems as a result of the condition. Previous to the common use of the MRI, the only people who would have ever been diagnosed with Chiari were those for whom the malformation was large and the effects were very obvious.