repetitive nerve stimulation
Also written as: RNS
An electrodiagnostic technique using repeated nerve stimulation to assess neuromuscular junction function.
Full Definition
Repetitive nerve stimulation (RNS) is a specialized electrodiagnostic test used to evaluate neuromuscular junction disorders such as myasthenia gravis and Lambert-Eaton myasthenic syndrome. The test involves stimulating a motor nerve with trains of electrical impulses at various frequencies (typically 2-3 Hz for slow RNS and 20-50 Hz for fast RNS) while recording the compound muscle action potential amplitude. In myasthenia gravis, slow RNS reveals a decremental response (progressive decline in amplitude), while Lambert-Eaton syndrome may show incremental responses with fast stimulation. The test requires careful technique and temperature control for accurate interpretation.
Usage
Usage note: Commonly abbreviated as RNS; specify stimulation frequency and muscle tested for clinical relevance.
In Context
- "Repetitive nerve stimulation revealed a 15% decremental response confirming myasthenia gravis." — Neuromuscular junction testing report
- "RNS testing was performed on the facial nerve with 3-Hz stimulation showing abnormal decrement." — Electrodiagnostic consultation