So MRI is one of my Specialties!
Titanium is fine in 99.9 percent of cases. Your average Mri only runs at 1.5 or even 3 Tesla (1 Tesla is the strength of the earth's mag field) at at these strengths Titanium is basically unaffected - I had my wedding ring made of it for this exact reason so I don't ever need to take it off. For the same reason implants made of it are totally fine.
The issue comes from Iron or steel. If it surgical steel and it has been in the body for a long time (over a year say) you can often get away with it as it will be so securely held in place in a 1.5 Tesla Mri but I wouldn't risk a stronger field than that.
And as for the eyes... The Eyes are the big risk for two main reasons:
1. If you ever worked with metal, cutting, sculpting, welding, plumbing etc. There is a chance of very small fine particles of metal getting into your eye where the action of the tears (and rubbing it) moves some of them back behind the eye into the orbit cavity where they sit and do nothing, causing no problems. You can't even tell they are there, could be there for decades.
2. If you have tiny fine particles of copper, iron or steel in your orbit when you go in an Mri... It pulls them extremely strongly to the centre of the field. In reality it means it pulls them from behind the eye, around the circumference then out the from (presuming your eye lid isn't closed) the metal is metal and Sharpe so as it moves it literally slices your eye open leaving large scars around your eyeball and in your eyelid as you close it due to what will be a lot of pain.
So Yeh it can blind you
