Pulsating right eyebrow

[Sharrock50]

Hi, I suffer an uncomfortable, often daily pulsating sensation above and below my right eyebrow which can sometimes develop into a full blown migraine and all its systems, but it can often just pulsate and just be annoying, coming and going all day. I take a nasal sumatriptan and am on Gaberpentin for prevention. Was wondering if any one else has similar symptoms. I understand that this is probably blood vessels dilating and causing pain in the surrounding area but would like to know what causes this and how I can prevent it, any thoughts? Many thanks