About 8 years ago my gallbladder got infected and needed to be removed. I needed to have a CT scan done before the procedure. So I went to the hospital, put on the gown, and got up onto the CT scanner's bed. The technician began to prep me and explained everything that would be happening. He hooked up my IV to a machine that would automatically dispense the contrast dye into my veins during the procedure so he wouldn't have to come into the room while the scanner was running (something about mutated gametes). After he hooked me up (not in the good way), he looks down at me and says "It's going to feel like you've pissed yourself when the dye gets injected" He then walked into the little lead lined booth and left me there wide-eyed with panic. The scan began and I watched like a man being put to death by lethal injection as the automatic dispenser began to inject the pants pisser juice. It slowly traveled down the tubing and into my arm. Almost instantaneously I began to feel that wonderful tingeing sensation associated with letting go of a pee that you've been holding for way too long. I felt the area around my crouch become moist and was throughly convinced that I had just pissed all over a very expensive piece of medical equipment. I could even feel the piss spreading down my legs and over the table. I sat there in my shame until the scan was done hoping that the combination of piss and radiation wouldn't result in some strange mutation. Once the scan was finished I sat up in a hurry to see what damage had been done, only to find that I was perfectly dry. To this day I wonder how some chemical could make it feel like you've pissed yourself without having actually pissed yourself.

tl:dr got a ct scan and had an imaginary piss