Bruns nystagmus: an important clinical clue for cerebellopontine angle tumours

A 24-year-old woman presented with gradual-onset left-sided hearing loss, progressive diminution of vision, headache and unsteadiness of gait. Comprehensive clinical evaluation revealed a left-sided lower motor neuron type of facial nerve palsy (figure 1), bilateral papilloedema, sensory loss in the distribution of ophthalmic branch of the left trigeminal nerve and cerebellar ataxia. Sensorineural hearing loss and absent corneal reflex were also observed on the left side. A coarse, left-beating nystagmus with leftward gaze and a fine primary-position right-beating nystagmus which increased on rightward gaze, consistent with Bruns nystagmus (video 1), were appreciated. In view of the clinical findings, a diagnosis of a space-occupying lesion involving the left cerebellopontine angle was considered. MRI of the brain documented a space-occupying lesion (4×3.5 cm) in the left cerebellopontine angle, most likely a vestibular schwannoma (figures 2 and 3). The condition was explained to the patient and …