Forget surgery. Join a choir which sings S.A.T.B. and work at it. Your voice will deepen (unless you join the Soprano section). I am an alto. Because we were short of blokes I ended up as chief Bass (took a year). I can now range 3 octaves from top to bottom A. Just working at it does the trick.
Yeah, but the trouble is folk sticking their head around the door enquiring what was going on, and claiming thinking someone was in pain. It's a miracle anyone can work on their voice.