I hear the standing EMG is the definitive test, but I've never had one. Yet, I've had 3 neurologists agree with my diagnosis by the first one I saw ( first one left area, then 2 temps!), who went mainly by symptoms, observation, and having me do the " drunk" walk, and usual neurological tests. Presently I'm under the care of my PCP only till I get a new neurological, where I've moved to. Oh yes, a couple did the " helicopter sound " test.