Myasthenia Gravis Support Group
Myasthenia gravis (MG) is a neuromuscular disease leading to fluctuating muscle weakness and fatiguability. The hallmark of myasthenia gravis is muscle weakness that increases during periods of activity and improves after periods of rest. Although myasthenia gravis may affect any voluntary muscle, muscles that control eye and eyelid movement, facial expression, and...
Do you know which test(s) are being proposed? You may have to talk to the insurance company and find out why and then appeal it if the doctor and you think the tests are needed.
Couple of links with testing info
http://www.mayoclinic.com/health/myasthenia-gravis/DS00375/DSECTION=tests-and-diagnosis
http://neuromuscular.wustl.edu/mtime/mgdx.html
The tensilon test can be done in an office - but although it can give a neuro a good idea of what is going on, I don't think a positive test definitely means you have MG. I think this test can be positive in other diseases as well.
Good luck and definitely call first!