Agreed. I recently had one at my optometrist's office. He's treating my brother's glaucoma and I had an OCT scan of my optic nerve to look for any early signs of glaucoma.
if i'm correct, this test uses bright flashes. if you've ever squinted when someone takes your picture, imagine that 100 times brighter. it's not too bad but sure not painless. if you need it, your optometrist will send you. you won't have to ask. but i think it's not covered by ohip (or maybe it wasn't but is now), so unless you have an eye condition that warrants it, why would you do it? it won't hurt to ask your ophthalmologist, i wouldn't bother asking an eye-glass doctor.
When I took my test, it wasn't uncomfortable at all. You look into a blue light dot and it is not at all unpleasant. Apparently, this test detects problems at the very earliest stage.
BTW: I'm glad this thread got some hits. I realize it won't be popular as it does not involve the penis or a female doctor shoving her finger up a man's bum.