Evaluation of pure tone and speech discrimination changes in Usher's syndrome

Twenty-three adult patients with type 2 Usher's syndrome were evaluated for changes in pure tone average (PTA), discrete frequency thresholds, and speech discrimination scores. These patients were evaluated over a period of 5 years on the average (range, 2 to 9 years). Analyses of ear data showed a less than 10-dB change on PTA and discrete frequency thresholds for most ears. Of the ears that showed a threshold change greater than or equal to 10 dB, statistical significance was reached only at 4,000 Hz (p less than .01), where 11 ears representing ten patients dropped 10 to 15 dB. Speech discrimination data showed a greater than or equal to 16% change in score for 18 ears (12 patients). Sixteen of those ears (ten patients) had a 16% to 52% decrease in score (p less than .01), and the remaining two ears (two patients) showed a 20% and 30% improvement in score. These findings document little or no change in pure tone sensitivity for type 2 Usher's syndrome patients, but demonstrate the importance of monitoring their speech discrimination performance.