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[Assessment of patients with sudden hearing loss by transcranial Doppler ultrasonography].

OBJECTIVES
We evaluated the utility of transcranial Doppler ultrasonography in determining the vascular pathology in patients with sudden hearing loss.


PATIENTS AND METHODS
The study included 13 patients (11 males, 2 females; mean age 46.6+/-17.7 years; range 18 to 66 years) with a diagnosis of sudden hearing loss. Patients having chronic otitis media or other middle ear diseases or a history of surgery in the affected ear were excluded. All the patients were evaluated by pure-tone audiometry, impedance audiometry, transient evoked otoacoustic emissions, auditory brainstem responses, and transcranial Doppler ultrasonography. The results were compared with those of a control group of 19 age- and sex-matched healthy subjects (12 males, 7 females; mean age 46.8+/-6.9 years; range 33 to 58 years) who did not have any ear disease or a history of ototoxic drug intake or working in a noisy environment, and no pathology on otoscopic and audiometric examinations.


RESULTS
Compared to the normal ear, the mean blood flow and systolic flow velocities of the vertebral artery were significantly decreased, and the mean pulsatile index was significantly increased on the affected side. The mean flow velocity of the basilar artery in the patient group was lower than that found in the control group.


CONCLUSION
Transcranial Doppler ultrasonography can be used for the evaluation of vascular involvement of the vertebral and basilar arteries in patients with sudden sensorineural hearing loss.