CONE-BEAM CT OPPORTUNITIES IN THE ASSESSMENT OF SIGNIFICANT SURGICAL ANTHROPOMETRICAL INDICATORS OF MIDDLE EAR STRUCTURES IN DIFFERENT TYPES OF TEMPORAL BONE STRUCTURES

Abstract

Multislice computed tomography (MSCT) is widely used in ear surgery. With the development of cone-beam CT technology it’s become possible to perform CT with comparable precision and facilitate positioning, lower radiation dose and getting primary three-dimensional image. Currently there is no algorithm of three-dimensional tomograms analysis of the temporal bone as part of preoperative preparation in middle ear surgery. A retrospective analysis of 118 temporal bones tomograms made on the cone-beam tomography was performed, from which 58 temporal bones from 32 individuals were selected for study, each of which was related to one of three comparison groups according to the type of pneumatization. Structures of the middle ear were evaluated qualitatively and quantitatively (the depth of the antrum and the sigmoid sinus, antrum size, distance from the antrum to the sigmoid sinus, the presence of lateroposition and prelying sinus, bone wall thickness of the horizontal semicircular canal, facial canal near the aditus ad antrum, and the distance between them). Significant differences were found between anthropometric measurements, depending on the type of pneumatization and the presence of inflammatory changes in the temporal bone. The algorithm of three-dimensional tomograms of temporal bones analysis is proposed, which should be used in preoperative preparation and choosing of surgical access to the structures of middle ear.