Unilateral Sudden Deafness as a Primary Symptom of Pons and Cerebellar Peduncle Infarction: A Case Report

In sudden deafness, the central nervous system is rarely involved. We report a case with a sudden sensorineural hearing loss caused by an infarction of the vertebral basilar system. A 62-year-old male presented with a sudden onset of hearing loss and tinnitus in the left ear and dizziness. Audiogram showed a left-sided moderate loss of hearing which is greater in the high frequencies. Spontaneous nystagmus toward the right side was found and caloric test showed CP on the left car. Neurological examination demonstrated staggering gate, diminution in left corneal reflex and facial sensation and disability of heel-knee test indicating disorder in the cetral nervous system. ABR showed mild elongation of wave III and V latencies. He was urgently subjected to MRI, showing an infarction localized in the pons and the cerebellar peduncle. The present case indicates that neurootological examinations should be performed in initial examinations of sudden deafness patients not to overlook any retrocochlear lesions.