20 CFR §220.115

1. (a)What treatment the claimant must follow. In order to get a disability annuity, the claimant must follow treatment prescribed by his or her physician if this treatment can restore the claimant's ability to work.
2. (b)When the claimant does not follow prescribed treatment. If the claimant does not follow the prescribed treatment without a good reason, the Board will find him or her not disabled or, if the claimant is already receiving a disability annuity, the Board will stop paying the annuity.
3. (c)Acceptable reasons for failure to follow prescribed treatment. The following are examples of a good reason for not following treatment:
   1. (1)The specific medical treatment is contrary to the established teaching and tenets of the claimant's religion.
   2. (2)The prescribed treatment would be cataract surgery for one eye, when there is an impairment of the other eye resulting in a severe loss of vision and is not subject to improvement through surgery.
   3. (3)Surgery was previously performed with unsuccessful results and the same surgery is again being recommended for the same impairment.
   4. (4)The treatment because of its magnitude (e.g., open heart surgery), unusual nature (e.g., organ transplant), or other reason is very risky for the claimant.
   5. (5)The treatment involves amputation of an extremity, or a major part of an extremity.