This makes me think back to a business ethics class many many years ago and some of the fun stuff we'd debate. It kinda gets down to how badly you want to know what's on the roll versus guilt over the "right thing". You could say since you know who the person is, have some idea of how to contact them, and perhaps there might even be professionally related photos on it - what type of surgeon is this? Could be interesting if they are a plastic surgeon, but I digress. So, you could have fun with the argument that the "right" thing to do is make at least one attempt to see if they care to get it back. Or perhaps have fun with the argument that the person was so careless with their equipment etc. as to be of no issue to play finders keepers. But then again, maybe it was stolen from them, and that's why it as you received it. Not helping, am I?
Make sure you post back what you find after finishing it off.