SNAP
Pronunciation: SNAP
Also written as: SNAP — Sensory Nerve Action Potential
Sensory Nerve Action Potential - the compound electrical response recorded from sensory nerve fibers following stimulation.
Full Definition
SNAP (Sensory Nerve Action Potential) represents the summated electrical activity of sensory nerve fibers in response to electrical stimulation. SNAPs are recorded using surface or needle electrodes placed over sensory nerves or nerve branches, with stimulation applied distally or proximally depending on the study protocol. Key SNAP parameters include amplitude (measured in microvolts), latency (onset and peak times), and conduction velocity. SNAP abnormalities help diagnose and localize sensory neuropathies, nerve entrapments, and brachial or lumbosacral plexopathies. SNAPs are particularly valuable because they remain normal in purely motor conditions and radiculopathies proximal to the dorsal root ganglion.
Usage
Usage note: Always spell out on first use: Sensory Nerve Action Potential (SNAP). Express amplitudes in microvolts.
In Context
- "The median SNAP amplitude was reduced to 8 microvolts, indicating axonal sensory neuropathy." — Nerve conduction study report
- "All upper extremity SNAPs were absent, consistent with severe generalized sensory neuropathy." — Electrodiagnostic summary