system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why don't they use metal detectors before an MRI scan?

I've seen in TV shows that any ferrous metal in your body can be extremely dangerous during an MRI. I had an MRI recently, they made me sign that I don't have any of that, but that was it. Why don't they have, say, the same equipment TSA uses in airports? Is it too expensive or not sensitive enough?
gpt
I think it may just be an unnecessary expenditure since you are assumed to know if you have metal in your body, or it would at least be present in any medical records or be in there for some plausible known reason.