If you do it right the needle goes gently straight into his pupil where it.. somehow.. implants memories/data into his brain? I can't remember exactly what it was done for. It's some weird science **** .
It actually removes sensitive information that could only be retrieved otherwise if he was dead, as this was the only way to find the location of the Marker.
I never played dead space. It just seemed like much of the same tired ass jump scare **** , like Five Nights at Faggots, ******** : The Really Dark Percent, and Evil Without (good gameplay).
my case was rather special, i was only 13 and it was a cataract removal surgery.
"In cataract surgery, the lens inside your eye that has become cloudy is removed and replaced with an artificial lens (called an intraocular lens, or IOL) to restore clear vision. The procedure typically is performed on an outpatient basis and does not require an overnight stay in a hospital or other care facility."
they knocked me out, then cut my eye open, sucked out the cloudy part, added the lens then taped a bunch of gauze over my eye, had to leave it like that for about a week. they did 1 eye at a time, let it heal then did the other.
Honestly I found this to be less unsettling than the scene in Tales from the Borderlands when Rhys removes his implants manually to get Jack out of his head. Rips the arm off, then uses a shard of glass to dig the temple and eye implants out.