Blockage of reuniting duct in Meniere's disease

Abstract

The bony groove of the reuniting duct between the saccule and cochlea was visualized in all control subjects. However, the bony saccular orifice to the bony groove could not be visualized in the lesional ear of Meniere's patients with significantly greater frequency compared with those of the contralateral non-lesional ears and control ears (p < 0.01). This orifice was not patent in 66.7% (8 of 12 ears) on the lesional side but all contralateral non-lesional ears of the patients and normal control ears were patent.

Assessment of Meniere's disease from a radiological aspect – saccular otoconia as a cause of Meniere's disease?

“…This is based on experimental findings from cadavers showing that the bony groove appears vague when covered with CaCO 3 but not when covered with muscle fragments. The data from the present and previous studies [7] suggest that the occlusion may be situated between the saccule and the RD or the SD and the ES.…”

“…The patency of the RD was assessed on the orifice of the saccule to the RD based on our previous report [7]. The patencies of the SD and ES were analysed in the same manner by assessing the continuity of their bony grooves [6].…”

“…Additionally, we examined CT images of a cadaver with a small piece of muscle or small amount of calcium carbonate on the bony grooves of SD and ES to assess changes in the CT images, as in our previous report [7]. …”

“…Using this strategy, we reported that MD patients, defined as grade 3 by the criteria of MD from the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS), showed significant discontinuity of the bony groove of the RD in comparison with normal ears. This discontinuity suggests that the RD may be blocked by a radiodense substance [7], and this substance could represent dislodged saccular otoconia.…”

Vestibular function in Lermoyez syndrome at attack

“…Recently it has been suggested [14] that MD may arise because of a blockage of the ductus reuniens [15], which would cause an increase in intralabyrinthine Xuid volume resulting in the MD attack. On such an account, the enhanced utricular response at the MD attack could be due to increased Xuid volume possibly causing a deformation of the Xexible, tenuously attached, compliant utricular membrane [16] with changes to receptor hair cell functional responses and thus an enhanced utricular n10 response.…”