#chiari

What is CM1 and it's Comorbidities?

What are the symptoms?

What are the types of Chiari Malformation?

Why does CM1 happen?

What are the treatment options?

Pronunciation Guide:

What is Chiari Malformation?

Chiari (key-arr-ee) Malformation is a brain malformation in which the brain is too large, skull is too small, or some combination on the both, causing the cerebellar tonsils (and in some instances the brain stem) to slip through the skull and into the spinal chord.

Chiari is most typically a congenital effect. There are two main types (though they aren't the only ones). The most common of the two us Chiari 1, in which only the cerebellar tonsils are descended through the skull. The second most common, Chiari 2 (also known as Arnold-Chiari malformation) has more tissue herniation in the cerebellar tonsils and even the cerebellum, as well as brain stem herniation as well.

(See Below, the Cerebellar tonsils are marked in red while the brainstem is marked in green and yellow. This is considered a normal MRI)

Chiari malformation is likely to occur in 1 in 1,000 people, making it uncommon but not rare. The statistics are likely to be slightly higher than that for Chiari 1, as many people don't present symptomatically (and many incidents are only found in cases where the person was receiving radiological imaging for other instances such as head injury, so many people are unaware they had Chiari to begin with).

The only way to diagnose Chiari is through radiological imaging (many arguing upright MRI specifically is the only proper way to view the real level pf herniation). Herniation is measured down from the McRae line to the lowest point on the cerebellar tonsils. Depending on the accuracy of the machine (and which imaging tool is used) herniation can appear at different levels at different times. (See below, my first MRI looks markedly less in comparison to my second MRI, which features a roughly drawn on McRae line. In the second image I was noted to have a 7-8mm herniation.)

Symptoms

Chiari is marked by a number of symptoms and commorbidities, even moreso depending on the type you have. Symptoms can occur at any level of herniation. Some people with Chiari can have a 3mm descent and have debilitating symptoms, while some may have a 15 mm descent and be completely asymptomatic. The most common of these is occipital headaches & migraines, ranging from mild to severe, but many more are possible. These range from...

Balance Issues

Dizziness & Vertigo

Neck & Shoulder Pain

Difficulty Swallowing

Sore Throat

Sleep Apnea

Nausea & Vomitting

Tinnitus & Hearing Loss

Blurred Vision, Visual Snow, & Vision Loss

Muscle Weakness

Numbness or Pins & Needles (Caused by Nerve Damage)

Poor Motor Skills

Fatigue

Cognitive Difficulties (including but not limited to Brain Fog, Memory Problems, Confusion, & Difficulty Speaking)

Insomnia

Photophobia/Light Sensitivity

Syncope, Fainting, & Drop Attacks

Seizures

Dysautonomia

Since the cerebellar tonsils block the opening to the base of the skull, Chiari can halt the proper flow of CSF (Cerebral Spinal Fluid) between the brain and the spinal chord. Because of this, Syringomylia (cysts filled with CSF formed on the spine called Syrinxs) is considered common with Chiari. Other common disorders with Chiari are Scoliosis, EDS & Cervicocranial Instability, POTS, Tethered Spinal Chord Syndrome, Spina bifida, & Hydrocephalus.

So What's the Solution?

Well, the only known solution for Chiari as of right now is surgery. This surgery is called posterior fossa decompression-- in which a small portion of the base of the skull is removed from the Chiari patient to relieve pressure and give more room for the brain. The surgeon can then do for sone patients a duraplasty, in which the dura (or opening of the brain) is cut open and a patch of tissue is sewed into the incision to make the dura bigger and give even more room for the brain. Surgery can also be done as a preventative measure against syrinxes for those without them. In the case the patient also has a syrinx, more surgical procedure can be done to drain the cyst. In patients with EDS, special procedures must be made to avoid surgical complications and making things worse.

Surgery is not guaranteed to completely alleviate symptoms, but typically helps with some. However, due to large misunderstanding and disagreement on proper diagnostic traits of Chiari from doctors (most typically neurologists and neurosurgeons) many may be denied surgery for a number of years, and Chiari Diagnosis can take on an average of 4 years to officially receive.

Some go years experiencing symptoms and having "low lying cerebellar tonsils" (or similar language, such as incidental tonsillar ectopia) noted on their radiology reports without doctors officially recognizing it as Chiari. In this time many are misdiagnosed with other disorders such as chronic headaches, multiple sclerosis, fibromyalgia, and more before finally finding a doctor who will listen. Many will brush off the radiological findings as just a difference in your brain being formed at birth before admitting the symptoms can be due to Chiari. It can take years of your own patient advocacy before someone finally listens.

This is why awareness to it is so important, in hopes of reaching other people and doctors and forming a stronger understanding of the condition from information found by experts on it and those with Chiari themselves. With more awareness comes more accessibility to treatment and surgery so those who are symptomatic can hopefully find some relief. So this month send a little love & luck to those with Chiari!