What are brain tonsils on mri?

Cerebellar tonsils:

- Also known as cerebellar tonsillar ectopia.

- Downward herniation of the cerebellar tonsils through the foramen magnum in the occipital bone that connects the cranial fossa with the spinal canal.

- Typically occurs in patients with Chiari I malformation.

- Associated with symptoms that include neck pain, headaches, dysphagia, sleep apnea, vertigo, dizziness, and motor or sensory disturbances

- May be incidentally found in asymptomatic patients.