Hi,
Thank you for posting your query.
This condition is called
Chiari malformation. In this condition, the
cerebellar tonsil drops down through the foramen magnum (opening in the lower part of skull bone) into the
spinal canal, and thus, presses onto the lower part of brain (
brainstem) and upper cervical
spinal cord.
If the compression on the brainstem or cervical cord is significant, then, a surgery is required, called as foramen magnum decompression.
Chiari malformation is normally present since birth.
I hope my answer helps. Please get back if you have any follow up queries or if you require any additional information.
Wishing you good health,
Dr Sudhir Kumar MD (Internal Medicine), DM (Neurology)
Senior Consultant Neurologist
Apollo Hospitals, Hyderabad, India
Click on this link to ask me a DIRECT QUERY: http://bit.ly/Dr-Sudhir-kumar
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