Electrophysiologic techniques to study the upper cervical nerves are scarce. Some of these nerves are superficial and easily accessible for nerve conduction studies. The great auricular nerve, a purely sensory branch of the cervical plexus has
been
documented to be abnormally thickened and to be easily palpable in patients with leprosy, inherited or non-inherited hypertrophied neuropathy and even in some normal subjects. The nerve is also easily susceptible to neck injury because of its
anatomical
pathway. It supplies the skin over the mastoid and the back of the lower part of the auricle.
We have described and compared with two different techniques for evaluating nerve conduction test of the great auricular nerve, using only the surface stimulating and recording electrodes. The first one by kimura is recorded at earlobe and the
second
one by Palliyath is recorded at mastoid process region. The results such as peak latencies, amplitudes, durations and velocities of sensory nerve action potentials by theses techniques are summarized as follows; 2.01±0.68 msec, 17.05±4.82μV,
1.02±0.17 msec and 46.02±6.43m/sec on earlobe, and 1.7±0.10 msec, 14.19±5.12μV, 0.66±0.13 msec and 46.67±5.66m/sec on mastoid process, respectively.
There was no statistical significance between the results of two different methods. We have concluded that we may use these two different techniques interchangeably for the study of great auricular nerve conduction.
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