I have chronic headaches dr. has scheduled a mri of the brain. why ? what is he looking for?

Not sure.Ask your Dr: If this is the 1st severe headache after trauma / accident, or the "worst headache of your life", then MRIs are performed to exclude subdural hemorrhage (brain bleed). If you've had them since birth, Arnold-Chiari malformations can be seen. However, most MRIs for chronic headaches in adulthood are negative (i.e., reveal normal brain or findings that don't cause headaches). So, ask your Dr. b4 MRI.