Endolymphatic Sac Decompression and Shunt Insertion - For Meniere's disease
Endolymphatic Sac Surgery is performed in patients with Meniere's disease to stop or help control the vertigo attacks. It is occasionally performed to stop a progressive hearing loss from continuing to decline.
Endolymphatic Sac Surgery is the most preferred surgery that has the potential to reverse what is going awry in the ear but maintain the residual balance and hearing at pre-operative levels.
The procedure is done on an outpatient basis in the hospital or surgery center under general anesthesia. It takes around 1-1.5 hours.
An incision is performed behind the ear and the mastoid bone is opened. In this process, the bone is removed from the base of the back of the brain through the mastoid until the endolymphatic sac is identified. Bone is then completely removed from the sac.
A laser is used to make a hole in the outer layer of the sac, and a silastic shunt called an Austin shunt is inserted through the hole into the sac. The incision is closed, and the person is brought to the recovery room and goes home about an hour after waking up.
The cause of Ménière's disease is unknown. But it may be related to a fluid imbalance in the inner ear. This fluid (endolymph) is contained in a part of the inner ear called the endolymphatic sac. Two surgeries may be done:
- In case of endolymphatic shunt surgery, a small tube, or shunt, is inserted in the endolymphatic sac to allow excess fluid to drain. When the excess fluid can drain, pressure does not build up and vertigo does not occur.
- In case of endolymphatic sac surgery, a small amount of bone is removed from inside the ear. This provides more room for the endolymphatic sac when it swells with too much fluid. When there is more room for the sac to swell, the pressure inside the inner ear is avoided and vertigo does not develop.
Antibiotics are taken for a week to prevent infection. There is little pain and most people use over the counter medications for the pain. Vicodin is occasionally used.
The patient can return to work the following day. The hearing is clogged for a few weeks and then gradually returns to normal.
The biggest risk is that this surgery may not be effective. Vertigo attacks may be unchanged in severity or frequency. 10-25% of patients may feel they have not benefited from the surgery. Vertigo is seldom worsened by the surgery
Hearing Loss: The hearing can worsen after surgery, but this is rare. About 25% of patients will have improved, or more stable hearing. Rarely can there be a significant worsening of hearing, but Meniere's disease does cause fluctuation in hearing and so this can also occur immediately after surgery.
Tinnitus: This is usually unchanged by the surgery. It can occasionally worsen, but this is rare. Some patients can hear their heartbeat in the ear after surgery.
Facial Nerve Injury: This can occur after any ear surgery. It is extremely rare.
Spinal fluid leak: This is extremely rare but can lead to meningitis.