HSC Section 8_April 2017

ENDOLYMPHATIC SAC SURGERY FOR ME´ NIE` RE _ S DISEASE

To further assess long-term efficacy of ESS, we ana- lyzed studies that provided both short-term and long-term follow-up data in the same cohort of patients. Although we were unable to assess differences between ESS sub- types, we were able to analyze all current ESS techniques (sac decompression and mastoid shunts) as a collective group. At approximately 16 months, current ESS proce- dures demonstrated a high efficacy of vertigo control with 72.6% achieving complete or substantial (Category A/B) vertigo control (Fig. 18 and Table 5). With a mean follow-up of approximately 6.5 years, vertigo control decreased to 63.4%, a statistically significant change ( p = 0.004; Fig. 19 and Table 5). The decrease in vertigo control may reflect the degree of overall ESS failure in the long term or may simply reflect the progression of disease in this cohort of patients. In conclusion, ESS (sac decompression or sac shunting) controls vertigo in the short term ( 9 1 yr of follow-up) in at least 3 of 4 patients with MD who have failed medical therapy, without prior trial of intratympanic steroids or gentamicin. In the long term, vertigo control with the pooled patient data demonstrates a similar 75% Category A/B result. It should be noted, however, that the long-term results are less favorable when the same cohort of patients is followed up over time (73% control at 16 mo follow-up versus 63% at approximately 6.5 yr of follow-up). There is no statistical difference between sac decom- pression and mastoid shunting procedures in controlling vertiginous symptoms or preserving hearing in the short- term or long-term follow-up periods. There is also no dif- ference in vertigo control between shunt procedures with and without silastic. There is, however, a statistical differ- ence in hearing preservation, both in the short and long term, between shunting with and without silastic, in favor of no silastic. This analysis raises the issue of using silastic in ESS. Although vertigo control is similar in the short and long term, silastic sheeting seems to have a small but statistically significant adverse effect on hearing. In our opinion, a fair assessment would be that once the sac is opened, placing silastic does not add benefit and may be deleterious. CONCLUSIONS 1. Committee on Hearing and Equilibrium guidelines for the diagnosis and evaluation of therapy in Me´nie`re’s disease. American Academy of Otolaryngology Y Head and Neck Foundation, Inc. Otolaryngol Head Neck Surg 1995;113:181 Y 5. 2. Pearson BW, Brackmann DE. Committee on Hearing and Equi- librium guidelines for reporting treatment results in Me´nie`re’s dis- ease. Otolaryngol Head Neck Surg 1985;93:579 Y 81. 3. Alexander TH, Harris JP. Current epidemiology of Me´nie`re’s syn- drome. Otolaryngol Clin North Am 2010;43:965 Y 70. 4. Pullens B, Verschuur HP, van Benthem PP. Surgery for Me´nie`re’s disease. Cochrane Database Syst Rev 2013;2:CD005395. 5. Claes J, Van de Heyning PH. A review of medical treatment for Me´nie`re’s disease. Acta Otolaryngol Suppl 2000;544:34 Y 9. 6. Santos PM, Hall RA, Snyder JM, Hughes LF, Dobie RA. Diuretic and diet effect on Me´nie`re’s disease evaluated by the 1985 Committee on REFERENCES

These findings may further implicate silastic as a poten- tial contributor to worse hearing preservation.

Long-term Analysis The natural progression of MD (continued hearing loss, ‘‘burn-out,’’ etc.) complicates analysis of long-term sur- gical results (4,54,82). Several studies have attempted to compare ESS outcomes to nonsurgical outcomes (natural history) in patients with MD (54,82). In the study by Silverstein et al., complete vertigo control was obtained in 71% and 70% of patients in the group not operated on and the group who underwent subarachnoid shunt sur- gery, respectively, at 8 years of follow-up. Quaranta et al. performed a similar study that resulted in 74% and 85% vertigo control at 6 years of follow-up in the groups not operated on and the group who underwent mastoid shunt surgery, respectively. In our analysis, we were unable to compare the natu- ral history of MD to ESS. We did, however, analyze the long-term efficacy of current endolymphatic sac pro- cedures. With approximately 3 years of follow-up, sac decompression achieved 81.6% Category A/B vertigo control compared to 75.7% for current mastoid shunt techniques (Table 3). This difference was not found to be statistically significant ( p = 0.09). Further, at similar follow-up times, sac decompression and current mastoid shunt techniques achieved relatively similar rates of hear- ing preservation (71.6% versus 69.3%, p = 0.59; Table 4). The mean PTA worsened by 1.4 dB in the sac decom- pression group and by 6.0 dB in the current mastoid shunt group. The significance of this difference, however, could not be statistically determined because the raw data were unavailable, and, as with the short-term conclusion, may not be clinically relevant. In the long term, both mastoid shunt with and without silastic achieved similar rates (75.3% versus 79.0%, p = 0.22) of Category A/B vertigo control (Table 3). Long- term hearing preservation differences were consistent with our short-term analysis, as the group with silastic sheet placement had worse hearing preservation compared to the group without silastic sheet placement (64.4% versus 79.8%, p = 0.0001). This difference was noted to be sta- tistically significant, despite nearly an additional year of follow-up for the nonsilastic group (Table 4). Interestingly, mastoid shunt without silastic placement maintained a statistically significant higher rate of hearing preservation in the long term compared to sac decompression (79.8% versus 71.6%, p = 0.05). This suggests that opening of the sac (mastoid shunt), but not inserting silastic, does not negatively impact hearing outcomes in the long term and may actually be beneficial. Sac Decompression Versus Mastoid Shunt (With and Without Silastic) in the Long Term Mastoid Shunt With Silastic Versus Mastoid Shunt Without Silastic in the Long Term

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