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
No hay comentarios:
Publicar un comentario