Hello all, I am in Douglaston. I just has a few questions. I see that the 3 most popular Doctors are Dr. Ren, Garber, and Geiss. I was wondering what the differences in the 3 where. Do they all require the same pre op tests? A liquid diet before surg? I would appreciate any information you could give me. Also if anyone hasn't used one of these 3 doctors please let me know.