Below is an instruction from Human. Write a response.
    ### Instruction:
    How to diagnose Renal Artery Stenosis ?
    ### Response:
    A health care provider can diagnose RAS by listening to the abdomen with a stethoscope and performing imaging tests. When blood flows through a narrow artery, it sometimes makes a whooshing sound, called a bruit. The health care provider may place a stethoscope on the front or the side of the abdomen to listen for this sound.
    