There are three main diagnostic gold standards for myasthenia gravis: 1) electromyography, based on low-frequency repetitive stimulation, to see if there is a decreasing amplitude of electromyography, if there is, the test is positive; 2) neostigmine test, if the patient’s symptoms of myasthenia gravis improve within a short period of time after the injection of drugs, it is also positive; 3) acetylcholine antibody test, acetylcholine is an important transmitter between nerves and muscles, there are In some patients, because of the problem of the neuromuscular junction, the transmitter will be abnormal, and the acetylcholine antibody produced by itself will attack the neuromuscular junction of itself, and then the exchange of information between nerve and muscle will be abnormal. The presence of this antibody in the blood is also an important indicator for the diagnosis of myasthenia gravis. Generally, if two of the three tests are positive, the diagnosis of myasthenia gravis is made.