Infracochlear access to the petrous apex (morphometrics)
DOI: 10.32364/2587-6821-2021-5-7-486-491
I.A. Anikin, N.N. Khamgushkeeva
Saint-Petersburg Research Institute of Ear, Throat, Nose and Speech, St. Petersburg, Russian Federation
Aim: to study morphometrics data of the infracochlear tunnel on the cadaveric temporal bones, sufficient for its rehabilitation.
Patients and Methods: the study was performed on 30 cadaveric temporal bones. The measurement was made using a measurement probe, a micrometer ruler, and a digital caliper. The following parameters were studied: the distances concerning the location of the facial nerve in relation to the infracochlear tunnel; the distances between the anatomical structures of the infracochlear tunnel in its various sections (from the internal carotid artery to the jugular vein); the length of the infracochlear tunnel (bisector drawn between the internal carotid artery and the jugular bulb to the basal whorl of the cochlea); the depth of the infracochlear tunnel (distance to the petrous apex from the basal whorl of the cochlea). A comparative analysis of the results obtained with the data of other scientific studies was conducted.
Results: infracochlear access on the cadaveric temporal bones was performed in our study only on 18 cadaveric temporal bones (60% of cases). During surgical access to the petrous apex, a 2 mm cutter was used to avoid injury to adjacent vessels.
Based on the obtained data, differences in the structure of the infracochlear tunnel were noted depending on the pneumatization of the petrous apex. The main parameters of the infracochlear tunnel have been determined, which can be applied in the choice of surgical tactics for the removal of pathological formation from the petrous apex.
Conclusions: there are the following anatomical prerequisites for conducting infracochlear access to the petrous apex for its lavage: infracochlear tunnel width from 5 mm, infracochlear tunnel length from 5.5 mm, the distance between the mastoid part of the facial nerve to the anterior margin of the cochlea window from 4.8 mm. These parameters can be applied in the assessment of patients’ CT scans to determine the indications for infracochlear access to the petrous apex.
Keywords: petrous pyramid, petrous apex, infracochlear tunnel, infracochlear access, cadaveric temporal bones, morphometrics.
For citation: Anikin I.A., Khamgushkeeva N.N. Infracochlear access to the petrous apex (morphometrics). Russian Medical Inquiry. 2021;5(7):486–491 (in Russ.). DOI: 10.32364/2587-6821-2021-5-7-486-491.
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