P 460 Evaluation of eye and lid movement characteristics during blink reflex using scleral search coil

IZAKI A., SHIMO-OKU M. Deparfment of Ophthalmology, Hyogo College of Medicine (Japan) Puroose : Blink reflexes evoked with comeal sensation or flash light stimulation are widely performed to examine optic, trigeminal and facial nerve. Both the electro-oculographic findings of lid movements and scleral search coil findings of eye movements during those blinks were investigated previously, we studied both eye and lid movement simultaneously with special reference to the co-ordination of those movements evoked with several stimuli and compared them with those of voluntary blink. Methods : Eye and lid movement was studied in five normal subjects. The data was obtained using scleral search coil ; Enzanshi-Kogyo MEL24. And the records were digitized and estimated using San-Ei Signal Processor 7T18. Program was written in the Basic. &2& : The amplitude of eye movements shows 7.9+6.8deg. 9&15.0deg, 6.2*6.0deg, velocity shows 226.9i150.0deg/sec. 228.9&202.6deg/sec, 140.3+45.4 deg/sec, duration shows 158.0f74.9 ms, 162.9f90.2 ms, 118.6+49.2 ms under voluntary blink, cornea1 touch stimulation and light stimulation respectively. Those for lid movements shows 11.1+8.5deg, 3.%3.8deg, 5.0+5.8deg, velocity shows 204.2+131.7deg/sec, 162.3&70.0deg/sec, 123.6f64.9 deglsec, duration shows 154f55.1 ms, 165.0+57.8ms, 150.41t65.9ms under voluntary blink, cornea1 touch stimulation and light stimulation respectively. Qg&&& : Peak velocity and amplitude of both eye and lid movements were decreased under cornea1 touch stimulation and flash light stimulation. It is interesting that both lid and eye movement are affected by changing of the stimulus.