Is he part of an MS Clinic?
Either way, I've found it really helps to get things off on the right foot to start the conversation with something like "I really need your help...".
It seems that a lot of doctors behave better, and really try to help if they get a little "ego stroke" right off the bat

.
Wishing that you have a good experience and get some answers this time around

.
With love, Erika