Susan, here are five visualization exercises you can do before submitting yourself to a dreaded medical procedure:

--Imagine yourself in front of a huge glass window. Outside, you can see a tall building with many windows. In the windows you are witnessing different people going through their personal lives and personal dramas. Everyone is oblivious of everyone else. 

--Imagine yourself on a beach, contemplating the golden sand. You are a grain of sand among other grains of sand. Take a handful of sand and wait for the cloak of humility to fall on your shoulders.

--Imagine yourself in outer space. Thank the universe for selecting you to undergo this trial, for you know that, had it happened to any one of your loved ones instead, they would not be able to withstand it because they do not have the strength that you have.

--Imagine yourself surrounded by your ancestors, who are watching over you and ensuring that nothing bad will happen to you.

--Imagine yourself siting in the middle of a giant, pink lotus with a thousand petals, and that you are glowing with a soft, pink light.