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Date of last update: 10/04/2017.

Forum Name: Neurology Topics

Question: Tonsillar ectopia

 MA_and_mom_of_3 - Mon Aug 20, 2007 10:23 am

My 3 yr and 11 month old son just had an MRI for tethered spine. This came up negative but was positive for tonsillar ectopia. He has asthma and is currently taking Nasonex, Albuterol inhaler as needed, and Pulmicort Nebs at night. He also has Dx of ADHD, ODD, and Bi-polar. Can you explain what tonsillar ectopia (mild) is, does it need treatment, what are our treatment options, could any of his mental dx's be from this finding? There isn't much on the internet about this so if you could just expand on this in general, any information would be helpful. Thank you for your time!
 Dr. Chan Lowe - Thu Sep 13, 2007 10:50 pm

User avatar Hi MA_and_mom_of_3,

Tonsillar ectopia refers not to the tonsils in the throat as some may think. Instead it refers to the tonsils of the cerebellum in the brain. At the bottom of the cerebellum there are two "bumps" known as the cerebellar tonsils.

Normally they are completely within the skull. The term ectopia basically means mispositioned. In tonsillar ectopia, the tonsils are lower than normal such that the begin to lye outside the skull (defined as below the foramen magnum, the large opening at the base of the skull that the spinal cord goes through).

A condition called Chiari malformation is when this condition is exaggerated such that the tonsils are stretched into a pointed shape.

Tonsillar ectopia can be associated with increased headaches and neck pain but commonly is asymptomatic and is incidentally found when a person has an MRI for some other reason. The term mild indicates that your son's case has only very slight displacement of the cerebellar tonsils lower than they should be.

I hope this helps some. Best wishes.

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