[Differential perilymph fistula diagnosis].

If sudden unilateral deafness accompanied by vertigo and spontaneous nystagmus on the afflicted side occurs during birth, a perilymph fistula with rupture of the round window membrane caused by pressure has to be considered. A 35-year-old pregnant patient was presented with the aforementioned symptoms on the day she gave birth to triplets. During examination, surditas and a paranasal hyposensitivity were found on the right side. Furthermore, a spontaneous nystagmus on the affected side occurred which was not suppressed by fixation. The nystagmus was apparent as a direction-fixed gaze nystagmus. Saccades during smooth pursuit testing as well as a lack of the auriculofacial reflex during contralateral stimulation of the deaf ear could be observed. Magnetic resonance imaging (MRI) of the skull revealed a fresh hemorrhagic cavernoma of the cerebellar pedunculi. This rare lesion caused a nerve compression of the fifth and eighth cranial nerve due to perifocal edema. Neurosurgical intervention was not necessary because of subsequent spontaneous resorption of the lesions and abatement of the deafness within a few days.