I've been there. I'm a few decades older than your son, and I got a full page of details noting about 20 different things. And they were all irrelevant or normal.

I know that it looks scary. We think that a reasonable person would say "It's all ok except this one minor bulge around L4/L5" But they can't say that because of liability issues.

The radiologist must note everything. If he doesn't, his employer's legal counsel will worry about possible exposure to liability.