[The ability of gap detection in patients with acoustic neuroma]

Objective:We aimed to provide a basis for the clinical study of acoustic neuroma through investigating the ability of temporal gap detection in acoustic neuroma patients and comparing the abilities with those in people with normal and impaired hearing. Method:Twenty-two patients with confirmed acoustic neuroma, 30 normal hearing patients and 16 patients with sensorineural hearing loss were enrolled in this study, and the interval threshold for awareness of each group was tested. Result:The mean temporal gap detection test（TGDT） threshold of the normal hearing group was （3.56±0.82） ms; the sensorineural hearing loss group's was （3.91±1.46） ms; TGDT threshold of healthy side of acoustic neuroma patients was （4.01±1.86） ms; TGDT threshold of the impaired side of acoustic neuroma patients was （9.48±9.46）ms. After statistical analysis, we found that excepting for the test of phonetically balanced maximum （PBmax） and TGDT, other results in the sensorineural hearing loss group and normal hearing group is of no statistical difference. The difference between the affected side of the acoustic neuroma group and the other groups was statistically significant （P<0.05）. There was no linear correlation between the value of TGDT threshold and PBmax （P> 0.05）. TGDT value of normal people has no significant difference among people of different genders and ears of different individuals. Conclusion:The TGDT of the healthy ear of the patients with acoustic neuroma is not affected, and there is no significant change compared with normal people. The TGDT test has a good consistency with the PBmax results. The time interval response ability of the affected ear of the acoustic neuroma is significantly weaker than that of the normal person. The combined test of PBmax and TGDT will contribute to the diagnosis of retrocochlear disease.