Question

Patients with MG show an electrical abnormality on Rep Stim called a decrement. This means there is a decrease in ________ after the first response to a train of stimuli

a) Amplitude
b) Latency
c) Conduction velocity
d) Duration

Answer 1

In patients with Myasthenia Gravis, the term 'decrement' refers to a decrease in amplitude of muscle response during repetitive nerve stimulation.

Step-by-step explanation:

Patients with MG (Myasthenia Gravis) show an electrical abnormality on repetitive stimulation (Rep Stim) called a decrement. This means there is a decrease in amplitude after the first response to a train of stimuli. In electromyography, decrement is measured as a decrease in the size or amplitude of the muscle response to repeated nerve stimulation, and is indicative of neuromuscular junction disorders like MG. This decrement occurs because with each successive nerve impulse, fewer acetylcholine receptors at the neuromuscular junction are activated, leading to a progressively weaker muscle response.