Single fiber electromyography (SFEMG)

What is Single fiber electromyography (SFEMG)? ? 

Single fiber electromyography is a technique that enables the recording of single muscle fiber discharges, either during volitional contraction or during electrical stimulation of the axon branch to the muscle fiber.

Mathematical analysis of consecutive Single fiber electromyography signals enables quantitation of the variability in transmission time across the Neuromuscular Junction from discharge to discharge, a value known as jitter .

In Myasthenia Grevis, LEMS, and other Neuromuscular Junction disorders, jitter is increased and may be associated with intermittent failure of transmission across certain Neuromuscular Junctions (“blocking” of neuromuscular transmission).

What does Single fiber electromyography show in Myasthenia Grevis?

Single fiber electromyography is the single most sensitive test for Myasthenia Grevis and is positive in 95% of generalized cases and 90% of pure ocular cases. Increased jitter also occurs in myopathic and neuropathic diseases, so careful routine electromyography and nerve conduction studies are imperative to rule out these causes before Single fiber electromyograph can be interpreted.

15585

Sign up to receive the trending updates and tons of Health Tips

Join SeekhealthZ and never miss the latest health information

15856