My dominant left vertebral artery 'abutes' my brainstem without compression. my right vertebral artery is hypoplastic terminating in pica. 10+ radiologists say this is common variation & neurologists say shouldn't cause symptoms. true?

It is not feasible to provide a more meaningful opinion, in this forum, than that provided by neurologists who examined you and your imaging studies. For healthy diet: http://www.choosemyplate.gov/., exercise 30 minutes/day, drink enough water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs.

Anatomic anomalies of the vertebral arteries are not uncommon, and typically, there is no reason to worry. (Do wonder what symptoms prompted a vascular evaluation of the posterior extra cranial circulation?). Agree with your doctors' opinions. If you feel uneasy, discuss the matter further with those who know you best.