If I have cataracts and elect to have them removed it is deductible. If I elect to have a face lift that's not for a medical reason then it's not deductible. See:
There is surgery that is elective as to when it is performed and then there is elective surgery that is purely for personal purposes.
Cataracts is an eye disease and could be delayed since it is not life threatening.
Reconstruction of a face because of a dog attack, birth defect, or accident is not elective and is deductible, but a face lift just because there is some lose skin is purely for personal reasons.
If you can get diagnosed with a disease by a licensed professional or have a licensed professional make the determination that one's health is being endangered by a physical condition, then the procedure is necessary even if the time of the surgery can be selected.
"Medical care expenses must be primarily to alleviate or prevent a physical or mental defect or illness."