Nothing looks like hydrocephalus imaging that I've seen, but I don't think you've got the best views of ventricles shown. I will look later on an actual monitor, maybe the phone screen and viewing before morning caffeine changes my perspective. Note there are pics online that show examples of hydrocephalus on imaging. It may be that a more general forum or chiari forum might be appropriate places to ask in, any forum people with more familiarity with imaging hang out.

The bulge you refer to, if you mean 7006 image, is in the back of your head. I'm not sure if you are saying front of pic or other. Any time a view like that isn't symmetric is notable, so expect them to note that in the report. Some odd looking imaging can just show odd, but not concerning, things. I do know some tumors can cause hydrocephalus by blocking csf flow.