• The effects of aditus blockage, decrease of tympanic cavity volume, and resection of the tensor tympani muscle on umbo displacement were studied in human temporal bones using a new noncontacting video measuring system. This system, combined with stroboscopic illumination, allowed measurement of umbo vibration down to 0.3 μm in the 0.1- to 4.5-kHz frequency range for a constant 124-dB sound pressure level at the tympanic membrane. Aditus blockage caused a mean increase of 5.4 dB with a peak at 2.8 kHz and a mean decrease of 3.4 dB below 1.6 kHz. Decrease of the tympanic cavity volume by 30% to 42% showed an improvement of 2.2 dB in the 1.4- to 3-kHz range and a similar loss below 1 kHz. Resection of the tensor tympani muscle produced a slight improvement of 1.7 dB at 1.8 kHz.
(Arch Otolaryngol Head Neck Surg 1986:112:1262-1268)
Gyo K, Goode RL, Miller C. Effect of Middle Ear Modification on Umbo VibrationHuman Temporal Bone Experiments With a New Vibration Measuring System. Arch Otolaryngol Head Neck Surg. 1986;112(12):1262–1268. doi:10.1001/archotol.1986.03780120026004