Differences between endolymphatic duct blockage and endolymphatic sac drainage surgery in the reversal of endolymphatic hydrops in patients with Meniere’s disease, preliminary results

To explore the differences between endolymphatic duct blockage (EDB) and endolymphatic sac drainage (EDD) surgery in the reversal of endolymphatic hydrops (EH) in patients with intractable Meniere’s disease (MD). A total of 19 MD patients receiving EDB (n=10) and EDD (n=9) treatment underwent gadoliniumenhanced inner ear magnetic resonance imaging (MRI) scans prior to, 2 weeks after and at >12 months following surgery. In the EDB group, the second MRI revealed no changes in EH, whereas the third MRI revealed a reversal of vestibular EH in 3 patients and a downgrading of cochlear hydrops in 2 of these 3 patients, who presented with an improvement in their hearing and complete control of vertigo. In the EDD group, the second MRI showed a reversal of EH in 4 patients, and no changes in EH in the remaining 5 patients, whereas the third MRI showed that those 4 patients who presented with a reversal of EH at the second MRI stage remained unchanged, with the exception of one patient who experienced a recurrence of vestibular hydrops. All 4 patients exhibited a complete control of vertigo, although hearing improved in only 1 of them, worsened in 1 and remained unchanged in 2. The present study showed the reversal in EH was likely due to the delayed effect of surgery accompanied by an improvement in hearing in EDB group, whereas the reduction in the endolymph volume presented as an acute reversal of hydrops in EDD group without a causeeffect relationship with hearing function.