Social Security periodically reviews your disability or blindness to decide if you are still disabled or blind. If you are no longer disabled or blind, Social Security will stop your benefits.
Social Security calls this review a Continuing Disability Review (CDR). The law requires Social Security to perform a medical CDR approximately every 3 years, unless Social Security determines you have a condition that they expect will improve sooner than that. However, if you have a condition that is not expected to improve, they will still review your case, but not as often as every 3 years.