Rach, What's a boffin? Is it someone silly, cause then I can respond.

The Single Fiber EMG is a hard test to do. Even someone who has done hundreds can have a hard time doing it. And then it takes about two hours to analyze. So you not only have to do the test well but to analyze it well.

A borderline jitter would be indicative of a problem. Did you have the test done while on any meds like steroids or Mestinon? If so, it would make the test negative. Some people with MG are so bad that they can be on meds and have a positive SFEMG though.

From what I know from an MG expert, a borderline result would and should push a doctor's thinking in the direction of MG IF there is other clinical evidence supporting that diagnosis.

People with MG are diagnosed without a positive EMG. It's a clinical diagnosis backed up with positive tests. And a negative test doesn't prove anything.

I'm sorry you have not heard back from Dr. Vincent. And I'm really sorry these doctors don't have the faith in what they are seeing to help you.

Annie