A deviated septum is a medical condition that can interfere with breathing and with the ability to taste, and may require treatment. Both Medicare Part A (for hospital costs) and Medicare Part B (for doctor and other outpatient costs) could cover that treatment, but only if your doctor determines that the treatment is "medically necessary" and Medicare agrees. In other words, just because treatment of a deviated septum – a minor surgical procedure in the doctor's office or a more serious surgical procedure in the hospital – may be possible, it's not always medically necessary. The treatment might not be considered by Medicare to be medically necessary if the condition doesn't interfere with your breathing, or if the procedure has a very low chance of improving your breathing.
If you are considering medical treatment for a deviated septum, discuss the Medicare "medical necessity" question with your doctor. If the doctor has any doubt about Medicare coverage of any treatment being considered, the doctor can submit to Medicare a request for approval of the treatment before you have the treatment. That way, you'll know for sure whether Medicare is covering it.