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Updated: May 20, 2026

Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
Changes in Dermatomal Somatosensory Evoked Potentials according to Stimulation Intensity and Severity of Carpal
Soo-Youn Sohn1, Jeong-Hwan Seo, Yong Min
1Department of Physical Medicine and Rehabilitation, Research Institute of Clinical Medicine, Chonbuk National University Medical School and Hospital, Jeonju, Korea.
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 1.5×sensory threshold (ST) and 2.5×ST were used on both normal and CTS patients.
Results:
In moderate CTS, the latencies of C6 and C7 DSEP during 1.5×ST SI and those of C7 DSEP during 2.5×ST SI were significantly delayed compared with the values of normal subjects. Significant correlation between the latency of C7 DSEP of 2.5×ST 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.
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