Auditory evoked potential alterations induced by pulsed ultrasound.

摘要: • Diagnostic levels of pulsed ultrasound were applied abdominally over the uteri pregnant rats for five minutes daily during first 20 days gestation. The average energy output machine at optimum focal length transducer (5.4 cm) was 7.2 mW/sq cm. Postnatal auditory evoked potentials demonstrated a significant alteration in offspring treated animals when compared with similarly treated, but nonexposed controls. This only occurred high frequency range. Neither light nor electron microscopy revealed morphologic alterations cochlear elements exposed offspring. Although deficit range known to be important rat's hearing, several issues make this data reassuring clinicians using diagnostic ultrasound: total amount exposure higher than would expected human use, defect mild, and absence clear-cut abnormalities may indicate presence minimal, or even reversible, defect. (Arch Otolaryngol1985;111:309-314)