Stop in for a cup of coffee

Anybody know how long you have to stay in the tube for a shoulder MRI? I am not a fan of tight spaces. Pretty sure they won’t let me do four doubles before I go in? I will close my eyes control my breathing and count backwards from a thousand!

Last MRI machine I was on was a deafening experience. Like they were firing a .22 pistol right next to my head every 15 seconds.