抄録
The effect of the intracranial use of an ultrasonic surgical aspirator with an electric striction transducer on the common carotid artery and nervous tissues was studied in anesthetized adult cats.
Experiments were performed without suction to investigate the effect of ultrasonic emulsification alone. The intensity of the ultrasonic vibration was fixed at 60% of the maximal vibration (240 μm). Saline was irrigated over the tip of ultrasonic aspirator at a flow rate of 5 ml/min. The temperature rise produced by ultrasonic vibration was studied by use of a thermistor buried in the brain parenchyma of animals 2 mm from the ultrasonic vibratory tip. No rise above the physiological range could be observed.
The effect of ultrasonic vibrations on the nervous system was studied using trigeminal evoked potentials (TEP) to monitor nerve function. An ultrasonic vibratory probe was applied to the cerebral cortex, brainstem and semilunar ganglion of trigeminal nerve. No significant changes on TEP occurred during or after application of ultrasonic vibration on any occasion. The common carotid artery and cerebral cortex exposed to ultrasonic vibrations were studied histologically. The changes were localized only in the superficial layer at the site of ultrasonic application.
These experimental results suggest that damage to the nervous tissue and major vessels by ultrasonic vibrations can be prevented by keeping the intensity of vibration to less than 60% and avoiding continuous use of ultrasonic vibrations.
