Nerves Conduction In Myasthenia Gravis


Electromyogram (EMG) and nerve conduction studies
Normal:
The EMG recording shows no electrical activity when the muscle is at rest. There is a smooth, wavy line on the recording with each muscle contraction.
The nerve conduction studies show that the nerves send electrical impulses to the muscles or along the sensory nerves at normal speeds, or conduction velocities. Sensory nerves allow the brain to feel pain, touch, temperature, and vibration. Not all nerves have the same normal conduction velocities. They generally get slower as a person gets older.
Abnormal:
Electrical activity in a muscle at rest shows that there may be a problem with the nerves used by the muscle. Abnormal wave lines when a muscle contracts may mean there is a muscle or nerve problem. Examples include a herniated disc, amyotrophic lateral sclerosis (ALS), and inflammation.
In nerve conduction studies, the speed of nerve impulses is slower than normal for that nerve. Slower speeds may be caused by injury to a nerve or group of nerves.

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