In Meniere’s disease, the patient experiences vertigo, which is a feeling of spinning of your head, along with tinnitus and fluctuating hearing loss. This disease is usually found among people in the age group of 40-50, although it can occur in any age group. The exact causes for the formation of Meniere’s disease are not known. But it is believed that the change in volume and composition of the fluid in the inner ear is the root cause for Meniere’s disease.
Inner ear consists of a soft structure called membranous labyrinth which contains endolymph fluid. Membranous labyrinth also contains hair like sensors inside them. The movement of the fluid inside the labyrinth is sensed by the hair like sensors inside the labyrinth and is communicated to the brain. The change in volume and composition of the fluid inside the labyrinth stimulates responses in the hair like sensors which are transferred to the brain and causes balance problems.
Endoymphatic Sac Decompression or Shunt Placement is a surgical procedure carried out to reduce the built up endolymphatic pressure in the inner cavity of the labyrinth. This procedure is usually carried out under general anesthesia. Entering through the mastoid bone, the bony covering of the endoymphatic sac is removed. The sac is now opened and a shunt tube is inserted. The tube acts as a shunt and the fluid from the sac is passed to a special cavity built in the surgery. The effectiveness of endoymphatic sac removal in controlling vertigo is doubtful. The success rate of this type of surgery has been reported to be as high as 90 % and as low as 50 %. This procedure is completed in about 2 hours and the patient can go home on the same day or the very next day.
The risk of this surgery includes hearing loss in about 2 % of the cases. Another important risk factor is the probability of facial paralysis as the facial nerves pass near the labyrinth area.