I have chiari which causes all kinds of migraines, dizzyness, zapping through head, flashing lights in vision esp. at night & with too fast head movement, etc. and many more chiari -related problems. The doctor also suspects I have increased cranial pressure, I'm on acetazolamide for that, not really helping though.
But I also have severe neck problems, it has lost the curve in it, many cervical bone spurs - some abutting spinal cord, and much degeneration in neck & dr.