The inverse of scuba diving is flying and most clipped or coiled patients report no effects. Scuba diving would increase pressure externally on the skull so if you had cranial sawing you might feel discomfort. How much, I haven't read by anyone. That said, you may want to try swimming in a pool at various depths using a gradual method to determine if you feel discomfort or pain on the skull. With respect to the brain and blood vessels, we all have internal pressure relief via expansion or contraction. The one issue that could arise would be with pressure on the blood vessel, especially the one that was clipped. The concern would be similar to having high blood pressure. In clipped or coiled patients, that needs to be controlled. Your Doctor or Neurologist could give you a more expert answer but I believe it would be similar to what I wrote here. Let us know what you find out.
Ok. I will ask my Neurologist at my next appointment. thank you