@ItchyKondera has given a fab thorough account of what it's like, I had one in August and I was terrified but it wasn't as bad as I thought and the nurses were lovely
My head was very slightly in the scanner but as PP said if you tilt your head back you can see the ceiling/room.
My experience was:
Went in, asked to fill out a form/answer questions. Taken through to have cannula put in (for the dye). Told them I was nervous about the whole thing, esp the dye, they said my DH could sit next to my head as long as he removed all the metal on his person
Got sent to changing room to remove underwired bra and anything else metal I had, put that in a locker
Taken into the room, laid down on the bed. Got given ear plugs (in ear) and ear defenders. Handed me the squeeze thing you can press if you want them to stop for any reason. Had something strapped over my pelvic area and a pillow placed under my head. Nurses explained what was going to happen and lovely one said she'd come and stand with me when the dye went in. They told DH he could stroke my head if he wanted to (he wasn't bloody listening and didn't touch me - twit)
The bed then moved into the machine, head was only just in - there was a sign above me on the machine that said 'do not look directly into laser' which I kept reading and trying to make different words out of the letters
The MRI tech said through the headphone things she was going to start and then it got noisy and clunky. Different noises for about 45 mins, very loud and repetitive. The bed will move a little for slightly different angles.
After 40 mins the nurse appeared and it was dye time. Felt cold going in, had a metallic taste in my mouth. 5 mins later it was done, the bed retracted and I was allowed to get up.
I went back to th changing room and put my bra back on/got my stuff.
Then I had to sit in the waiting area for 15 mins to ensure no reaction to the dye. They gave me a glass of water and I sat and chatted to DH.
15 mins later they called me back in to remove the cannula and asked me to fill out a patient satisfaction survey.
That was that. I'm not belittling it, I was nervous all the way through but they really put me at ease and it wasn't as bad as I thought it would be.
Good luck OP, you will be absolutely fine