Acute Transient Bilateral Deafness and Reversible Bilateral Loss of Chronic Tinnitus in Sequential Bilateral MCA Ischaemic Stroke
A 67-year-old patient had a right ischaemic stroke involving the right temporal and central cortex years ago resulting in a left-sided spastic hemiparesis.
He presented to the emergency department after having noticed acute deafness.
At the same time, a chronic tonal binaural tinnitus subsided completely.
Cranial MRI and FDG-PET imaging showed a chronic fronto-temporo-parietal right ischaemic stroke and a recent stroke in the rear area of the left insular cortex and the upper temporal lobe.
The condition remained stable for 3 days and hearing started to return during MRI.
With improvement of hearing after the MRI binaural tinnitus started again with a different character resembling the noise of the MRI machine.
A continuous improvement of hearing was observed over the following days and within one week the patient was able to communicate without problems except when exposed to acustic stimuli from several directions at the same time.
On follow-up 2 months later, the tinnitus had persisted without change of character while hearing was undisturbed for normal conversation.
Loss and recurrence of the chronic tinnitus during the second ischaemic stroke in the temporal lobe point to the functional relevance of the central auditory system for the chronic tonal tinnitus.
A growing number of functional imaging and neurophysiological studies demonstrate the importance of the central auditory system within the cerebral hemispheres for the occurrence of a chronic tonal tinnitus.
Fuente: Aktuelle Neurologie 2012;Vol 39(10):563 565