Analysis of computed tomography scans for development of differentiated approach to repair of ethmoid roof defects

Abstract

Study of the images before surgery in order to analyze the individual characteristics of the anatomy is the key to a successful surgery. Materials and Methods: Analysis of computed tomography data of 43 patients with defects in the ethmoid roof operated from 2010 to 2020 at the Burdenko National Medical Research Center for Neurosurgery. Patients were divided into two groups according to the localization of the defect and relapses. Results. With anterior defects, the angle between the line drawn through the nasal dorsum and the perpendicular drawn through the center of the defect to the bottom of the cavity is sharper than with posterior ones, p < 0.001. The height from the bottom of the nasal cavity to the ethmoid roof was greater with anterior defects than with posterior defects (p = 0.011). The height from the bottom of the nasal cavity to the cribriform plate with anterior defects is greater than with posterior ones (p = 0.006). When analyzing the ratio of the height of the middle turbinate and the distance from the septum to the orbit and when determining the length of the lattice roof anteriorly or posteriorly from the basal lamella, depending on the location of the defect with the length of the middle turbinate, it was found that the differences were statistically significant (p < 0.05). Conclusions. The posterior parts of the ethmoid roof are more likely to develop iatrogenic defects due to their lower location in relation to the bottom of the nasal cavity. For the correct choice of optics and instruments, the angle between the line drawn through the nasal dorsum and the perpendicular drawn through the center of the defect to the bottom of the nasal cavity matters. A middle turbinate flap can be used to seal both anterior and posterior ethmoid roof defects. The anatomical features of the ethmoid roof do not affect the incidence of relapses.