Sensorineural Hearing Loss Rate AMONG Patients Reffering to Khalili Hospital in Shiraz

Sensory – neural hearing loss following mastoid surgery has been Reported with different severities. In the mastoid surgery, different factors can affect hearing. The aim of this study was to introduce the most common frequency that was affected during mastoid surgery and also to determine the correlation between duration of drilling and suction irrigation with the severity of sensory – neural hearing loss. Th is Longitudinal Study was performed in the E.N.T department of Khalili Hopistal-Shiraz University of Medical Sciences. Thirty consecutive patients with chronic otitis media were selected. Audiometry was done (250Hz – 8kHz) in two occassions, one day before the operation and 2 months after the operation. The results were analyzed using paired T- test and Pearson Correlation. There was not any significant change in threshold of bone conduction in all frequencies (250HZ-8KHZ) after 2 months. The average time of drilling, was 46.6 minutes (SD 8.77). There was a significant correlation between the time of drilling, suction, irrigation and change in bone conduction threshold in the 4KHZ, (p<0.05) but this correlation relation was not found in the other frequencies. We did not find persistent changes in the bone conduction thresholds after tympanomastoid surgery in the operated ear and the other ear after two months. So in case of SNHL Consequence of surgery we should consider other factors.