Michael J. LaRouere, MD
Ménière's Syndrome, the name given the combination of fluctuating hearing loss, tinnitus, aural fullness, and episodic vertigo, is usually controlled with conservative measures, such as diet modification and diuretics. For patients with useful hearing, a variety of treatments can be employed for the 20 - 40% who continue to have disabling vertigo despite medical therapy. These options include endolymphatic sac surgery (ELS), vestibular neurectomy (VN), and either transtympanic or systemic (in the case of bilateral Ménière's - about 10% of patients) aminoglycoside treatment. The choice of options is based on hearing status, whether the disease is unilateral or bilateral, the patient's self-assessment of symptom severity and, after counseling, the patient's assessment of risk versus reward for each option available to them. This article focuses on patients who have useful hearing or do not wish to lose residual hearing and are, thus, not candidates for labyrinthectomy.
VN cures or controls vertigo in 95% of Ménière's patients but entails the risks of an intracranial operation. While section of the nerve via the middle fossa has some advantages, the increased risk to hearing, facial nerve function, retraction of the temporal lobe, and difficulty accessing the inferior vestibular nerve have led surgeons to largely abandon this approach in favor of the retrosigmoid approach. However, because the 8th nerve does not have a clear cleavage plane in the cerebellopontine angle complete section of the nerve without sacrificing fibers of the cochlear nerve is less reliable with the retrosigmoid approach
While the cure rate of vertigo is high, post-neurectomy dysequilibrium is common and in some reports imbalance is worse after surgery in 26% of patients. VN has the longest period of postoperative recovery before patients can return to work or driving.
Treatment of Ménière's syndrome with aminoglycosides was described in the 1950's, but fell out of favor due to a high incidence of hearing loss (in the case of direct administration to the ear through the eardrum) or oscillopsia (in the case of systemically-administered streptomycin). Use of these medications has enjoyed a renaissance recently as clinicians have sought minimally invasive options for Ménière's patients with persistent vertigo.
In the 1980's intramuscular injections of streptomycin in a protocol designed to blunt but not ablate vestibular function replaced the high-dose treatment used initially. This remains a useful option for individuals with bilateral disease or disease in an only hearing ear.
Since description of this procedure in the 1920s, debate has raged over the efficacy of this procedure, the mechanism by which it works, as well as issues of whether a shunt should be inserted or the sac simply decompressed. Its relative safely is well established. It has the advantage over ablative procedures of having lowest risk of hearing loss (1-2%) and fastest recovery time.
MEI introduced the concept of sac-vein decompression after observing apparent benefit when the sigmoid sinus was included in decompression. Using this technique, we found that after 2 years, vestibular symptoms were resolved or mild in 92%, 85% had stable or improved hearing, none had profound hearing loss. Our experience with ELS surgery has led us to continue to recommend it to patients with serviceable hearing and attacks of vertigo uncontrolled or poorly controlled by conservative management.