The Effect of Chronic Otitis Externa-Media on Brainstem Auditory Evoked Potentials in Dogs

The objective of the study was to present normative Brainstem Auditory Evoked Potentials (BAEP) data elicited by both air-conducted clicks (30 100 dBHL) and bone conducted clicks (100 1.30 dBHL) for healthy dogs, and dogs with chronic otitis externa-media (COEM). The data were analyzed to acquire reference values in 55 normal dogs and to estimate the degree of hearing, impairment associated with the disease. Filly-four dogs with COLM were divided into two degrees of security. The first one included dogs with severe (n 16), and the second with moderate COFM (n 38). The recognisability wave V was found higher than the others at every stimulation level. Wave VII was not seen by the bone-conducted click at all stimulation levels. and also in cases with severe COLM by the air.-conducted click. Recognisability of wave V was seen more than 50%, at 60 dBHL in severe COEM. This ratio was seen at 30 dBHL in moderate COLM. In healthy dogs, the latencies of waves (I VII) were compared between the left and the right side, and there were no significant differences between each side except tiff I shorter latency of wave VI. In conclusion, COEM caused increasing latency rather than total deafness, and BAFP can be suggested as an ancillary diagnostic tool in car disorders.