Question

The health care provider suspects a diagnosis of myasthenia Gravis in a patient who presented with progressive proximal muscular weakness, ptosis and dysphagia. Which test does the nurse expect will be ordered to confirm the diagnosis?

A: Lumber puncture

B: MRI

C: Repetitive nerve stimulation test

D: CT scan

Answer 1

Ans) C:Repetitive nerve stimulation test

Explaination:

- The next step is usually electrodiagnostic testing, in which electrodes are used to measure the electrical signals in muscle. Surface electrodes (similar to those used in electrocardiograms) deliver small shocks to a nerve in the arm, leg, or face, while other surface electrodes record the responses in muscle. In MG, a muscle’s response to repeated nerve stimulation declines rapidly. There are two types of tests that can be done to confirm the diagnosis of MG:

Repetitive nerve stimulation (RNS) is commonly used, with 75% to 80% accuracy and is described above.
Single-fiber electromyography (SFEMG) is a more sensitive test (with 95% accuracy) but is less widely available and technically demanding.