Περίληψη:
Objective: To demonstrate that the amount of basilar membrane
displacement toward the scala tympani and its attachment to the bony
wall of the scala tympani (i.e., interscalar septum) in hydropic
temporal bones is related to the intraosseous endolymphatic sac volume.
Study Design: A retrospective analysis of temporal bones from
individuals with the histopathologic diagnosis of “endolymphatic
hydrops.” Methods: Fifty-two temporal bones, from 38 patients, with
the histopathologic findings of “endolymphatic hydrops” were
analyzed microscopically. Data were obtained regarding the displacement
of the basilar membrane, endolymphatic sac volume, hair cell loss,
strial atrophy, ganglion cell loss, and last measured auditory
thresholds. The relationships between these variables were examined
statistically. Results: Nineteen of the 52 temporal bones (36.5%) with
endolymphatic hydrops showed displacement of the basilar membrane toward
the scala tympani in the apical and middle segments of the cochlea. A
reduced volume of the endolymphatic sac was significantly related to
increased severity of basilar membrane deformation (Rho = -.646; P less
than or equal to .001). Multiple regression analysis showed that
severity of basilar membrane deformation was the single best predictor
of low frequency thresholds while loss of hair cells was the best
predictor of pure-tone average threshold. Conclusions: The displacement
of the basilar membrane in the apical and middle segments that may occur
with endolymphatic hydrops, to the extent that it impinges on the
interscalar septum, is related to a reduction in the intraosseous
endolymphatic sac volume.
Συγγραφείς:
Xenellis, JE
Linthicum, FH
Webster, P
Lopez, R
