The title of the article "Why pre-curved
modiolar hugging electrodes only cover the basal turn of the cochlea and not beyond that?" appeared to be asking a question, but on closer scrutiny the author appeared to know precisely the answer to that question.
The 3D-reconstructed images showed that in normal mature mouse cochleae, the majority of NMDARs were distributed on the
modiolar side of IHCs and close to the IHC nuclei region, while the AMPARs were distributed at the IHC basal pole region, on the
modiolar and pillar sides of IHCs (Figures 1(f) and 1(g) and Supplemental video 1).
A recent study on histopathology demonstrated that
modiolar defects may be due to high CSF pressure transmission into the inner ear as a result of EVA (14).
CT and MRI images were also evaluated for cochlear dysplasia, cochlear-vestibular dysplasia, and
modiolar hypoplasia based on published criteria [20, 29].
Decreased perfusion of the spiral
modiolar artery, which primarily supplies the middle and apical turns of the cochlea, has been thought to cause low-frequency hearing loss, as in that of typical MD [71].
The initial site of entry of lymphocytes into the inner ear is the spiral
modiolar vein adjacent to scala tympani-15, and thus the helper T cells are activated against the sensory and supporting cells within the cochlea.
The concept of
modiolar hugging electrodes places the contacts of the electrodes closer to the eighth nerve and spiral ganglia.
Endothelin-1induced vasospasms of spiral
modiolar artery are mediated by rho-kinase-induced Ca(2+) sensitization of contractile apparatus and reversed by calcitonin gene-related peptide.
On the other hand, the pre-curved
modiolar hugging (MH) electrodes are currently offered only by two CI manufacturers and that too for the average cochlear size [3].
Keithley, "Spiral
Modiolar vein: Its importance in inner ear inflammation," Acta Oto-Laryngologica, vol.
To accomplish this goal, most current electrode arrays are molded in a spiral shape designed to match the shape of the
modiolar wall.
However, the CT of patient 3 did demonstrate the presence of a dilated internal auditory canal fundus and a deficient
modiolar base.