Wednesday, September 24, 2008

Chiari's Syndrome

I promised that I would research and write about it.

The following is from the web site of the National Institute of Neurological Disorders and Stroke:

Chiari malformations (CMs) are structural defects in the cerebellum,
the part of the brain that controls balance.  Normally the cerebellum
and parts of the brainstem sit in an indented space at the lower rear
of the skull, above the foramen magnum (a funnel-like opening to the
spinal canal).  When part of the cerebellum is located below the
foramen magnum, it is called a Chiari malformation.

Usually this condition is more common in females than in males, and it can be found among persons of Celtic descent more than in any other ethnic group. That makes our patient - a Kuwaiti female - somewhat unique.

Also, the page that this quote came from discusses the types of Chiari malformations that can be found, all classified by type. Type I is the only type of malformation that can be actually acquired by injury or accident, and Type III is the most severe - this type can result in significant neurological deficit for the patient.

Reading about the types of malformations caused me to question whether or not a cerebral hemorrhage or any type of traumatic injury which can force the brain into the foramen magnum can be considered a Chiari malformation. After I considered it for a while, I came to the conclusion that this couldn't happen, simply because Chiari malformations seem to occur usually when the fetus is in utero. Traumatic injuries are sudden, and I suppose it wouldn't be appropriate to think that something like this could occur with the aid of the laws of physics in play.

The other thing that would make my question irrelevant or inappropriate is that usually someone with Chiari's has other conditions associated with it. The most common are Spina Bifida and Hydrocephalus.

Spina Bifida is the incomplete development of the spinal cord and its covering. The bones around the cord also do not develop completely, usually resulting in what looks like a sac at the base of the spine, and nearly always results in partial or complete paralysis.

Hydrocephalus is excessive cerebro-spinal fluid encirling the brain. This is ultimately life-threatening and can be fatal if not treated. At the very least it changes the shape of the skull and can also be the cause of various forms of mental defect.

Treatment and management can be as simple as pain medication or as complex as multiple surgeries to correct the defect.


AJ, NREMT-I said...

Is it possible your patient had Budd-Chiari syndrome and not an Arnold-Chiari malformation?

Walt Trachim said...

It is indeed - as I didn't have complete access to the patient's chart at the time, I'm not sure which variant she had.

I do know, however, that she was scheduled for surgery to correct whatever issue she was diagnosed with. That's what made me suspect a malformation, at least based on what I knew at the time.

Good question - thank you!

AJ, NREMT-I said...

I only know there are two conditions with similar names as I had a pt with an Arnold-Chiari malformation and I had to go look things up afterwards...

Thank you for the response. Keep up the blogging!