Sudden Hearing Loss
If the hearing loss happens suddenly or develops over a period of up to three days, it is called sudden hearing loss.
Sudden hearing loss may have various causes. The first aetiologic factor that must be excluded is a benign tumour of the auditory nerve (neuroma). This is why one of the first investigations that is requested in sudden hearing loss is CT-scan or MRI of the petrous bone (the bone which hosts the inner ear).
Other, identifiable from the history cause of sudden hearing loss, is the perilabyrinthine fistula. This happens due to high pressure difference between the inner ear and the middle ear cavity, as in diving, when the diver forces equalization by blowing with closed mouth and nose.
Unfortunately, in the vast majority of cases, the cause of sudden hearing loss is unknown, and we believe that two major categories of possible causes play the most important role: The vascular and the immunologic causes. Vascular causes include spasm and occlusion of the minute feeding vessels of the inner ear, while immunologic causes refer to immunological reactions of an infection, usually of viral cause.
Sudden Hearing Loss is considered an otological emergency. The sooner the treatment starts, the higher the chance for complete recovery of the hearing. There is no general consensus in its management. Several therapeutic regimens have been proposed, including:
– Medical treatment by mouth on an outpatient basis.
– Admission to Hospital and intravenous medical treatment, based on steroids and vasoactive drugs.
– Hyperbaric Oxygen (with or without medical treatment)
– Intratympanic steroid injection, typically performed in one to three sessions).
Unfortunately, no option seems to offer a better result over the rest. The final decision on the treatment depends upon the meticulous evaluation of the clinical and audiological data of every individual case. Lately, we tend to favour the intratympanic injection option, as it is easy, quick, painless, and is performed on an outpatient basis, not disturbing professional or other activity of the patient.