RESPONSE TO LETTER TO THE EDITOR: "IS MENIÈRE'S DISEASE A CONTRAINDICATION TO STAPEDECTOMY?"

Abstract

In Reply: We thank the authors for reading our article (1) with interest and for their valuable comments. We agree on the importance of properly differentiating the nature and etiology of vestibular complaints in any patient, especially in those in which multiple etiologies may be suspected. This is particularly relevant in the matter at hand, given that upwards of 30% of patients with otosclerosis report vestibular symptoms (2–7). Possible mechanisms include endosteal involvement of otosclerotic foci associated with vestibular hair cell loss (8), malfunction of the endolymphatic sac and duct (9), changes in the biochemical composition or radial flow of perilymph and endolymph (10,11), or the production of cupular deposits (12). Practically speaking, while there may be a variety of etiologies, the concomitance of otosclerosis and Menière's disease (MD) has been demonstrated, with the rate of symptomatic endolymphatic hydrops being nearly 30 times greater in otosclerosis patients compared with the general population. The importance of properly differentiating between MD and otosclerosis, not to mention any other vestibular disorder, is paramount in the initial evaluation and management of any dizzy patient. This becomes magnified when considering stapes surgery given the significant risk associated with violation of the oval window footplate in patients with endolymphatic hydrops (13). As discussed, distension of the saccule can cause close proximity or even adherence to the undersurface of the footplate, which puts the patient at risk for a dead ear should the saccule become violated during the fenestration process. For this reason, we adhere to the dictum proposed by McCabe in 1966 (6) that patients should demonstrate at minimum 6 months of medically stable Menière's disease without an episode of fluctuating hearing loss or vertigo before stapes surgery. In theory, this would indicate adequate control of endolymphatic pressure and could allow for resolution of saccular distention, thereby reducing the immediate surgical risk. As patients in our review were only offered stapes surgery following a minimum of 6 consecutive months of stable Menière's disease, our results may only be generalizable to similarly well-managed patients. With regards to evaluation and management, our institutional practice is in line with the American Academy of Otolaryngology–Head and Neck Surgery Clinical Practice Guidelines (14), which recommends against routine vestibular function testing or electrocochleography to establish the diagnosis of Menière's disease. We do routinely obtain audiograms in these patients who also undergo clinical vestibular testing as part of our standard physical examination protocol. As such, we follow the guideline recommendations to diagnose patients meeting criteria of probable or definite Menière's disease. Those with an uncertain diagnosis may go on to have formal electrophysiologic vestibular testing. Following our review, all patients included for analysis met criteria for definite MD, however there was not enough compelling electrophysiologic vestibular testing data to report. As the authors suggest, there is growing evidence to support the use of video head impulse testing (vHIT) and vestibular evoked myogenic potentials (VEMPs) in addition to caloric testing to more comprehensively evaluate the vestibular system (15,16). As we use clinical outcomes to guide therapy, we do not routinely order or track changes in electrophysiologic vestibular testing. As such, the patients reported in our study were counseled on surgical options and risks of otosclerosis without routine vestibular testing. We acknowledge the limitations of our sample size and hope that this report is a catalyst for further study into this difficult to manage patient population. Evidence regarding the role of a comprehensive vestibular evaluation for the selection of appropriate surgical patients would be a welcome addition to our shared body of knowledge, however this was outside the scope of this report. Our study aim was to review the surgical outcomes of the relatively rare stapedotomy in patients with concomitant otosclerosis and Menière's disease. The results support the conclusion that medically stable Menière's disease need not be considered an absolute contraindication to stapes surgery, as some smaller studies have previously suggested (13). Despite this conclusion, we continue to share your expressed caveat that such cases should be taken on judiciously.