Antidromic sensory conduction measurements of median nerve in the forearm of 26 men were performed at intervals before and for 15 minutes following ultrasonic application over a segment of the nerve.

The ultrasound(Us) was applied over the area of the median nerve for 8 minutes at a frequency of 1 MHZ. continuous wave and using 1.5 watt/sq cm² dosage.

Nerve bed temperature was continuously monitered during the study via a subcutaneous needle(26 Gauze, 3 cm) thermistor probe.

Also infrared was irradiated to 26 healthy subject, from the height 75 cm for 8 minutes and after then, the subcutaneous temperature and median nerve conduction latency was measured. Continuous Us and infrared irradiation treatment were associated with increased temperature(0.8^oC) and shortened latendy(0.1 msec, 0.09 msec, respectively), namely similar lavels and patterns for NCV and subcuraneous tissue temperature were observed for the the continuous Us and infrared radiation.

It was concluded that the mechanical effects of Us were not significantly operative in this study. The increased velocities associated with continuous Us and infrared radiation treatments were attributed to a thermal-heating effect.

Keywords :Ultrasound, Median nerve, Sensory nerve conduction, Infrared, Temperature