I think you are trying to get to analytical. The name and cause do not change how it makes you feel. Most doctors do not have an accurate way to further define most head ache or vertigo. They just knwo how to group two symptoms together. We can too. We call the group of symptoms, PCS. It is a vague term because there are so many symptoms that fit in the PCS group.

The medical establishment uses these grouping for diagnostic and billing purposes. The IDC and CPT codes are just to try and simplify the paperwork. With managed care, insurance companies limit the care for certain diagnostic codes. This helps them do that.