How can repeated nerve stimulation assist in diagnosis?

Repeated nerve stimulation is a valuable diagnostic tool, particularly in the context of neuromuscular disorders. When applied effectively, it can help differentiate between myasthenia gravis and other conditions affecting neuromuscular transmission.

In myasthenia gravis, there is a decrease in the number of available acetylcholine receptors at the neuromuscular junction due to autoantibodies. During repeated stimulation, the ability of the muscle to respond diminishes, leading to increased muscle weakness with successive stimuli. This characteristic decremental response is a hallmark for diagnosing myasthenia gravis.

Other conditions, such as lambert-eaton myasthenic syndrome, may produce an incremental response upon repeated stimulation, which provides valuable diagnostic differentiation. Therefore, the application of repeated nerve stimulation not only aids in recognizing the presence of a neuromuscular transmission disorder but also helps narrow down the specific type of disorder based on the muscle's response to repeated nerve stimuli.