Detecting conductive hearing loss

Conductive hearing loss (CHL) in young infants can be detected well with Wideband reflectance (WBR) or tympanometry using probe frequencies of 678 and 1000 Hz, according to a joint study of American researchers. The goal of the study was to evaluate the effectiveness of tympanometry and WBR in detecting conductive hearing loss (CHL) in young infants. The researchers found that Ya measured with 678- and 1000 Hz probe tones was significantly different between ears with CHL and normal hearing (NH). Two-category classification of tympanograms using a 1000 Hz probe tone was significantly different between ears with CHL and NH. Neither two-category classification nor Ya was significantly different between ears identified with CHL and NH using a 226 Hz probe tone. WBR was significantly higher in the frequency bands 800 to 2500 Hz and in the frequency band centered at 6300 Hz in infants with CHL. Effect sizes (Cohen's d) were greater than 2 for several WBR frequency bands and Ya measured with 1000 Hz probe tones. The results were similar for calculations of Ya from admittance-magnitude and subcomponent tympanograms. Positive likelihood ratios for WBR ranged between 8.1 and 38, and those for Ya using 1000 Hz ranged between 12.5 and 32.

Source: Ear Hear, 2013 Jan 3

Rose Simpson