Vestibular Nerve Section
This operation is considered in patients who have severe Meniere’s disease with attacks of vertigo that continue despite aggressive medical management and still have good hearing in the affected ear. As it is the most invasive and risky of the surgical procedures offered for this condition, other options such as the Meniette device, Intratympanic steroid therapy and endolymphatic sac decompression are usually considered. If all other therapies are exhausted and the patient’s hearing is still useful in the affected ear, then this surgery is considered.
The patient is admitted to hospital after the operation and the length of stay is on average several days, with a 24 hour observation period in the Intensive Care Unit. This is because the operation involves opening the envelope of the brain, called the dura mater, either through the mastoid or via a craniotomy, depending on anatomy. The back of the brain, the cerebellum, is retracted delicately to reveal the vestibular nerve, which runs with the hearing fibers, the cochlear nerve, in the “vestibulocochlear nerve”, or the Viii cranial nerve. The fibers of the vestibular nerve are identified and carefully cut, leaving the cochlear nerve fibers intact. The landmark between these 2 sets of fibers is sometimes not clear.
The dura mater and the mastoid or craniotomy are then closed with a variety of materials, and the patient is observed in the intensive care unit. Because the balance fibers are cut suddenly, the surgery causes intense vertigo and imbalance for a few days requiring supportive medical care, medications for nausea and eventually physical therapy. A cane or walker may be needed for a while, depending on the patient’s health and activity level prior to the surgery. Once the patient is able to ambulate safely, he may be discharged home, but vestibular and balance therapy is continued on an out-patient basis to speed the patient’s recovery as much as possible. A return to full function occurs in most patients, although many do feel imbalanced when tired or stressed.
Pain and headache: These are usually short lived.
Hearing loss: The surgery is designed to eliminate balance fibers and maintain hearing fibers, but this is sometimes not possible. Hearing loss may occur, and be mile to profound. Total loss of hearing can occur in 5%.
Tinnitus: This usually occurs due to the hearing loss.
Facial Nerve injury: This can occur with any ear procedure and is rare. The facial nerve runs intimately close with the vestibulocochlear nerve and can be damaged during the nerve section. A facial nerve monitor is used to prevent this, and is successful in all but rare cases.
Spinal Fluid Leak: Spinal fluid is the fluid that bathes the brain and can leak out into the ear or the wound in any surgery when the dura mater is opened. This can occur in 5% of cases and is usually controlled with bed rest and medications. In some patients, a lumbar drain insertion or second surgery has to be performed to stop the leak. Spinal fluid leakage can lead to meningitis.
Infection and meningitis: Infection can occur after any surgery. When the dura mater is opened, meningitis can occur but is very rare