The aim of this study is to determine the normal values of the phrenic nerve conduction using magnetic stimulation of ipsilateral cervical roots in 30 healthy male adults.

In the present study, phrenic nerve function was evaluated by transcutaneous magnetic stimulation at the ipsilateral C3-4 level and recording the diaphragmatic action potential with surface electrode placed at the ipsilateral eighth-ninth intercostal space.

The results were as follows:

1) The mean latency was 9.3±1.0 msec at right, 9.3±0.7 msec at left, there was no significant difference between both sides.

2) The mean amplitude was 432±150μV at right, 456±141μV at left, there was no significant difference between both sides.

3) There was no significant correlation between the latency and the amplitude and variables such as age, sitting height and chest circumference.