What is Cerebellar Tonsillar Ectopia (CTE)?Â
Cerebellar tonsillar ectopia (CTE) refers to the downward displacement of the cerebellar tonsils (located at the lower part of the cerebellum) through the foramen magnum, the opening at the base of the skull. This can result in crowding of the craniocervical junction (CCJ) and compression of surrounding neural structures, including the brainstem and spinal cord. This crowding can also impede cerebrospinal fluid (CSF) flow causing a build up of pressure and toxins in the brain. ​
The most common symptoms include:
(1) Occipital headaches
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(2) Dizziness and balance problems
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(3) Numbness and tingling in the extremities
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(4) Neck pain especially at the base of the skull
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(5) Sleep disruption
Figure 1. Cerebellar tonsillar ectopia demonstrated on sagittal view of MRI.
What is Chiari?
Chiari malformations (CM) refer to structural abnormalities in the cerebellum, often affecting the brainstem and spinal cord. These malformations involve the downward displacement of cerebellar structures into or through the foramen magnum (much like the above described CTE but often more severe and with more complicating factors), which can cause neurological symptoms due to impediment of cerebrospinal fluid (CSF) flow and compression of neural tissue. Chiari is broken up into several different types including 0, 0.5, I, II, III & IV—all with different features, symptoms and severity. Below is a general overview of these different types:
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Chiari 0 (Zero)
This variant refers to patients who exhibit symptoms characteristic of Chiari malformations but lack clear cerebellar tonsillar herniation visible on imaging. Patients may have occipital headaches, dizziness and sleep disturbance. There may be crowding at the foramen magnum (the whole in the bottom of the skull that connects the brain and spinal cord) or a turbulent connection due to slight downward displacement that does not meet the classic 5mm of Chiai I. Additionally, abnormal CSF flow can be present as well.
Chiari 0.5 (Half)
A proposed intermediate category where cerebellar tonsils slightly extend below the foramen magnum (often 1–3 mm).​ Symptoms align with Chiari I but involve minimal tonsillar descent.​
Chiari I
The most common type, involving downward displacement of the cerebellar tonsils ≥5 mm below the foramen magnum.
Symptoms: Occipital headaches, dizziness, balance issues, and sometimes syringomyelia or sleep apnea.
NOTE: We do not treat or take on patients with Chiari II, III or IV. ​
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Chiari II
A more severe form associated with spina bifida (myelomeningocele). Chiari II includes herniation of the cerebellar vermis, brainstem, and fourth ventricle through the foramen magnum. Symptoms are much more severe and include hydrocephalus, feeding/swallowing difficulties, breathing irregularities, and significant neurological deficits.​
Chiari III and IV
Chiari III and IV are very severe and rare: diagnosed either in infancy or in utero.
How can Atlas Orthogonal help manage these symptoms?
Misalignment of the osseous structures in the CCJ can further exacerbate symptoms and increase pressure in the already crowded space. More research in this area is required to have definitive answers but there have been studies looking into how proper alignment of the atlas (C1) and axis (C2) can affect the symptoms CTE and chiari patients experience. We offer a safe, non-invasive approach to managing symptoms and require you to bring in your MRI and radiology report to make sure treatment is safe. Below are links to research articles regarding Atlas Orthogonal techniques and CTE / chiari.
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