Clinical Featues of 112 Cases of Acute Sensorineural Hearing Loss in Low Frequencies

Abstract

We have experienced 112 cases of sensorineural hearing loss in low frequencies between 1982 and 1993. The hearing loss, limitted in frequencies lower than 1kHz, abruptly occurs without vertigo and recurrence of attack is very rare. The etiology of the disease has been unknown, but prognosis of hearing loss seems to be better than that of other sensorineural diseases. This study was performed to explore whether hearing level at initial visit might effect recovery of hearing or not.
112 cases were classified into three groups depending extent of hearing impairment at their initial visit. The first group (I) consisted of 27 ears with slight hearing loss which sum of thresholds of low three frequencies (125, 250 and 500Hz) was less than 60dB. The second one (II) was 82 ears with medium hearing loss between 60 and 120dB, and the third (III) was 14 ears with severe one above 120dB. No difference of distribution in age and sex was seen among three groups. Three groups showed good recovery of hearing loss, and hearing level after more than three months of observation were 40.2±20.1dB in group I, 50.0±28.3dB in II and 41.7±35.1dB in III. No statisitical change was found in the final hearing levels of three groups.
Therefore, good recovery of hearing loss can be expected even if hearing loss at the initial visit might be slight or severe.