J Korean Neurosurg Soc.  2012 May;51(5):286-291. 10.3340/jkns.2012.51.5.286.

Changes in Dermatomal Somatosensory Evoked Potentials according to Stimulation Intensity and Severity of Carpal Tunnel Syndrome

• Sohn SY
• Seo JH
• Min Y
• Seo MH
• Eun JP
• Song KJ

• KMID: 2066928
• DOI: http://doi.org/10.3340/jkns.2012.51.5.286

Abstract

OBJECTIVE
To investigate the change of latency of cervical dermatomal somatosensory evoked potential (DSEP) according to stimulation intensity (SI) and severity of carpal tunnel syndrome (CTS).
METHODS
Stimulation sites were the C6, C7, and C8 dermatomal areas. Two stimulation intensities 1.5xsensory threshold (ST) and 2.5xST were used on both normal and CTS patients.
RESULTS
In moderate CTS, the latencies of C6 and C7 DSEP during 1.5xST SI and those of C7 DSEP during 2.5xST SI were significantly delayed compared with the values of normal subjects. Significant correlation between the latency of C7 DSEP of 2.5xST stimulation and the median sensory nerve conduction velocity was observed.
CONCLUSION
We suggest that these data can aid in the diagnosis of cervical sensory radiculopathy using low stimulation intensity and of those who have cervical sensory radiculopathy combined with CTS patients.

Keyword

Carpal tunnel syndrome; Dermatomal somatosensory evoked potential; Stimulation intensity; Stimulation threshold; Sensory radiculopathy

MeSH Terms

Carpal Tunnel Syndrome
Evoked Potentials, Somatosensory
Humans
Neural Conduction
Radiculopathy

Figure

• 

  Fig. 1 Significant correlation is noted between latency of C7 DSEP and sensory nerve conduction velocity (NCV) in CTS patients, (A) in total CTS patients, (B) in moderate CTS patients, during 2.5×sensory threshold intensity. r2 : Correlation coefficient, p : p-value. DSEP : dermatomal somatosensory evoked potential, CTS : carpal tunnel syndrome.

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