Significance of 125 Hz Pure-Tone Thresholds for Acute Low Frequency Sensorineural Hearing Loss / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: To analyze the 125 Hz pure-tone thresholds in patients with acute low frequency sensorineural hearing loss (LFHL) and to investigate the value of 125 Hz thresholds for the assessment of LFHL. SUBJECTS AND METHOD: Hearing tests including 125 Hz pure-tone were performed in 91 patients with acute LFHL ≤500 Hz and in 46 subjects with normal hearing. Patients with sudden sensorineural hearing loss or Meniere's disease were excluded. Inter-group and intra-group comparison of 125 Hz was made between LFHL and the control groups. RESULTS: There was a significant difference of mean pure-tone thresholds at 125 Hz between the acute LFHL and the normal groups (39.8±8.9 vs. 14.3±6.7 dB). Eight (8.8%) patients in the LFHL group showed normal thresholds at 125 Hz, but all other subjects were normal at 125 Hz in the control group. None with the average hearing thresholds at 250 and 500 Hz ≥40 dB had normal threshold at 125 Hz. There was a significant correlation between 125 Hz and other low frequencies in the LFHL group (250 Hz; r=0.81, 500 Hz; r=0.63). CONCLUSION: Not all patients with acute LFHL show abnormal hearing threshold at 125 Hz although every subject with normal hearing is within the normal limits at 125 Hz. Threshold assessment should be made at 125 Hz when a mild LFHL exists in the conventional pure tone audiometry.