Carotid Blockage and Surgery verse Non-Surgery

My Mother, who is 70 years old, experienced a TIA two weeks ago and the nurse practitioner at her physician’s office ordered a Carotid Doppler which showed blockage. I took her to a vascular doctor who ordered another test with contrast which showed she has a 70% blockage on one side and a 50-60% blockage on the other side. He wanted to schedule a surgery, but my Mother said she wanted to speak to him first (her appointment is this coming Friday). My Mother does not want surgery because of the risks and wants to know if there is any way to reverse this? She has been drinking Pom juice daily and eating healthy. She does not smoke, is not overweight, and does not have diabetes. She just started on blood pressure medicine because her BP was high. Any advice would be helpful. What should she be asking her doctor and is it more dangerous to put the surgery off (generally)?
Thanks.