My son got a concussion from getting hit in the nose during basketball practice. he just had an mri and his dr said he has a low lying cerebellum ?

Discuss with doc: The reason they probably did a poor job explaining this is it is usually a variation of normal. You had a procedure done that had an "incidental" finding (you weren't looking for it). The cerebellum is the back/bottom brain structure as it transitions into the spinal cord. It's position relative to the base of the brain can vary some. For rare people, if too low this is a trigger for bad headaches