An Angiogram definitely doesn't see arteries like arterioles, they are the thickness of a hair. I believe it takes a special type of MRI to look at these vessels.
What kind of biopsy? What about an angiogram? Would that be a regular angiogram or would the dr. have to go in the small artery or vessel and how would they know what vessel or artery to go in thru since it's a small artery or vessels. Can you see spasms in the small artery or vessel thru a regular angiogram without going in the small vessel or artery>