Impedance Audiometry in the Squirrel Monkey: Effect of Middle Ear Surgery

Abstract
• The two principal components of impedance audiometry, the tympanogram and acoustic reflexes, were measured preoperatively and postoperatively in seven squirrel monkeys subjected to experimental middle ear surgery. A probetone frequency of 1,200 Hz yielded both tympanograms and acoustic reflex thresholds roughly comparable to analogous data in humans at a probe-tone frequency of 220 Hz. Both tympanograms and acoustic reflex thresholds could be obtained reliably and with comparative ease. In general, postoperative data were modified in the expected fashion by the experimental middle ear surgery. Impedance audiometry appears to be a worthwhile and useful technique for monitoring middle ear status in the squirrel monkey. (Arch Otolaryngol104:214-224, 1978)