MRI of the cranium and orbits may also be performed to exclude compressive and inflammatory lesions of the cranial nerves and ocular muscles. Pulmonary function test
The forced vital capacity may be monitored at intervals to detect increasing muscular weakness. Acutely, negative inspiratory force may be used to determine adequacy of ventilation; it is performed on those individuals with MG.

Management
Treatment is by medication and/or surgery. Medication consists mainly of acetylcholinesterase inhibitors to directly improve muscle function and immunosuppressant drugs to reduce the autoimmune process. Thymectomy is a surgical method to treat MG. Medication
Worsening may occur with medication such as fluoroquinolones, aminoglycosides, and magnesium. About 10% of people with generalized MG are considered treatment-refractory. Autologous hematopoietic stem cell transplantation (HSCT) is sometimes used in severe, treatment-refractory MG. Available data provide preliminary evidence that HSCT can be an effective therapeutic option in carefully selected cases.Efgartigimod alfa was approved for medical use in the United States in December 2021. Acetylcholinesterase inhibitors
Acetylcholinesterase inhibitors can provide symptomatic benefit and may not fully remove a persons weakness from MG. While they might not fully remove all symptoms of MG, they still may allow a person the ability to perform normal daily activities. Usually, acetylcholinesterase inhibitors are started at a low dose and increased until the desired result is achieved. If taken 30 minutes before a meal, symptoms will be mild during eating, which is helpful for those who have difficulty swallowing due to their illness. Another medication used for MG, atropine, can reduce the muscarinic side effects of acetylcholinesterase inhibitors.
This is usually done using the accepted Myasthenia Gravis Foundation of America Clinical Classification scale. Physical examination
During a physical examination to check for MG, a doctor might ask the person to perform repetitive movements. For instance, the doctor may ask one to look at a fixed point for 30 seconds and to relax the muscles of the forehead, because a person with MG and ptosis of the eyes might be involuntarily using the forehead muscles to compensate for the weakness in the eyelids. The clinical examiner might also try to elicit the "curtain sign" in a person by holding one of the persons eyes open, which in the case of MG will lead the other eye to close. Blood tests
If the diagnosis is suspected, serology can be performed:

One test is for antibodies against the acetylcholine receptor; the test has a reasonable sensitivity of 80–96%, but in ocular myasthenia, the sensitivity falls to 50%. A proportion of the people without antibodies against the acetylcholine receptor have antibodies against the MuSK protein. In specific situations, testing is performed for Lambert-Eaton syndrome. Electrodiagnostics
Muscle fibers of people with MG are easily fatigued, which the repetitive nerve stimulation test can help diagnose. In single-fiber electromyography, which is considered to be the most sensitive (although not the most specific) test for MG, a thin needle electrode is inserted into different areas of a particular muscle to record the action potentials from several samplings of different individual muscle fibers.