MRI scan in the united kingdom?

many years ago i was a fabrication welder and use to get the odd spark in my eye from the grinder,at one time i had a spark but didn't go to the hospital as it wasn't playing up like others,the next time i got a spark in my eye i and went to hospital they got that one out but come across another one what they said was too deep in so they had to leave it in there,looking at how the MRI scanner works what is 10,000 to 30,000 times stronger than the magnetic field of the earth would this affect my eye.