If I am correct, and if she still works at this vet, Dr. Margo Mehl has experience with Yorkies. You could call and ask yourself, but I was given her name when I was working through a diagnosis of either MVD or Liver Shunt with my Yorkie. She is very knowledgeable in Liver Shunts and internal medicine/surgery, and being that Liver Shunts are more common in Yorkies than any other breed, it would make sense that she has a lot of experience with Yorkies. You could try to get in contact with her. Hope that helps.
Here is the Vet information, if she still works here.
San Francisco Vet Specialist