[DISCUSSION] Radiologists, how many MRI phantoms does your team have?

I got into an interesting discussion at work about an MRI sequence I've never used before. For context, I did a bunch of brain imaging in grad school, and now at work I'm encountering things that aren't the brain. Shocking.

The technique in question is trying to look at the amount of cartilage in a joint. I assumed the best way to identify potential problems with the MRI is to use a phantom like this one: https://www.truephantom.com/product/adult-knee/. We did this in grad school, but our phantom was basically an expensive jug of fancy water, which, apparently, looks enough like a brain to calibrate the machine.

It turns out the hospital just takes a random resident, puts them in the MRI, and takes MRIs of their joints. I'm assuming it's because the hospital doesn't want to pay $10k for a fancy fake knee.

So now I'm curious, if the radiologists and radiology-adjacent folks are out there, how many different phantoms do your teams own?