OBJECTIVE: To investigate the related parameters of temporal bone structure in the surgery of cochlear implantation through facial recess approach so as to offer a theoretical reference for the avoidance of facial nerve injury and the accurate localization. METHOD: In a surgical simulation experiment, twenty human temporal bones were studied. The correlation parameters were measured under surgical microscope. RESULT: Distance between suprameatal spine and short process of incus was (12.44 +/- 0.51) mm. Width from crotch of chorda tympani nerve to stylomastoid foramen was (2.67 +/- 0.51) mm. Distance between short process of incus and crotch of chorda tympani nerve was (15.22 +/- 0.83) mm. The location of maximal width of the facial recess into short process of incus, crotch of chorda tympani nerve were (6.28 +/- 0.41) mm, (9.81 +/- 0.71) mm, respectively. The maximal width of the facial recess was (2.73 +/- 0.20) mm. The value at level of stapes and round window were (2.48 +/- 0.20 mm) and (2.24 +/- 0.18) mm, respectively. Distance between pyramidalis eminence and anterior round window was (2.22 +/- 0.21) mm. Width from stapes to underneath round window was (2.16 +/- 0.14) mm. CONCLUSION: These parameters provide a reference value to determine the position of cochlear inserting the electrode array into the scale tympani and opening facial recess firstly to avoid potential damage to facial nerve in surgery.
OBJECTIVE: To investigate the related parameters of temporal bone structure in the surgery of cochlear implantation through facial recess approach so as to offer a theoretical reference for the avoidance of facial nerve injury and the accurate localization. METHOD: In a surgical simulation experiment, twenty human temporal bones were studied. The correlation parameters were measured under surgical microscope. RESULT: Distance between suprameatal spine and short process of incus was (12.44 +/- 0.51) mm. Width from crotch of chorda tympani nerve to stylomastoid foramen was (2.67 +/- 0.51) mm. Distance between short process of incus and crotch of chorda tympani nerve was (15.22 +/- 0.83) mm. The location of maximal width of the facial recess into short process of incus, crotch of chorda tympani nerve were (6.28 +/- 0.41) mm, (9.81 +/- 0.71) mm, respectively. The maximal width of the facial recess was (2.73 +/- 0.20) mm. The value at level of stapes and round window were (2.48 +/- 0.20 mm) and (2.24 +/- 0.18) mm, respectively. Distance between pyramidalis eminence and anterior round window was (2.22 +/- 0.21) mm. Width from stapes to underneath round window was (2.16 +/- 0.14) mm. CONCLUSION: These parameters provide a reference value to determine the position of cochlear inserting the electrode array into the scale tympani and opening facial recess firstly to avoid potential damage to facial nerve in surgery.