Influence of electrode array stiffness and diameter on hearing in cochlear implanted guinea pig

摘要: During cochlear implantation, electrode array translocation and trauma should be avoided to preserve residual hearing. The aim of our study was evaluate the effect physical parameters on hearing structures during insertion. Three prototypes with different stiffnesses or external diameters were implanted in normal guinea pigs via a motorized insertion tool carried robot-based arm, forces recorded. Array 0.4 0.4R had mm diameter prototype 0.3 diameter. axial stiffness set 1 for calculated from this as 6.8 0.8 (relative units), respectively. Hearing assessed preoperatively by auditory brainstem response (ABR), then at day 7 30 post-implantation. A macroscopic anatomy performed cochleae harvested examine scala location array. At 7, significantly poorer results than those (26±17.7, 44±23.4, 33±20.5 dB, n = vs 5±8.7, 1±11.6, 12±11.5 6, mean±SEM, respectively, 8, 16 24 kHz, p<0.01) (44±23.4 28±21.7 p<0.05). remained stable 30. maximal peak force higher (56±23.8 mN, 26±8.7 6). Observation showed that an incorrectly positioned fibrosis associated loss ≥40 dB (at kHz). An optimal position tympani flexible thin prevention primary objectives implantation.