Please don't feel that you need a muscle biopsy to go to Johns Hopkins. I have my first appointment in July 2014. They just want to know what you have done to plan ahead for your visit.They usually order certain labs/test ahead of time during your visit. My initial diagnosis during the time of appointment request was Myopathy and small fiber Neuropathy. Now that I have MG, gait abnormality and right sided weakness and abnormal MRI, I'm sure they will add or change my labs when they get my updated records.
They tend to do EMG irregardless of when you last had one . My evaluation has caused me thousands of dollars out of pocket in spite of excellent health insurance. Name the test and I've probably had it done. Its been very expensive to say the least. Best wishes on your evaluation. Don't worry about the muscle biopsy. My Neuro is trying decide if I need one with the MG diagnosis and abnormal MRI. Just get your docs to send whatever you have and they will decide if you need it before or after your visit.