비 기저부 비대칭의 빈도와 주변 비-안면구조와의 관계 분석

Abstract

Background and Objectives : The nasal floor tilting (NFT) is an incidental finding shown on the ostiomeatal computed tomography (OMU CT) image, created by an asymmetry in the levels of both nasal floors. Despite its frequent appearance, this finding has never been properly defined, and its correlation with asymmetry of the adjacent nasofacial structures was never investigated. This study aimed to reveal the incidence of nasal floor tilting in patients with sinonasal symptoms and find out its correlation with structures of the nasofacial skeleton. Materials and Methods : From January 2008 to July 2017, patients who had taken preoperative OMU CT as well as facial photograph were investigated. Patients under age of 20, with a history of craniofacial anomaly, prior nasofacial trauma or surgery, neoplasm in the head and neck area were excluded. The incidence of NFT and the degree of NFT angle was measured in 265 patients. Asymmetries shown on the adjacent nasofacial skeleton as well as in the external face were evaluated. Analysis on the incidental difference of adjacent nasofacial asymmetry upon the presence of the NFT was performed. The NFT, asymmetry in the orbital level, maxillary sinus level, and maxillary sinus size was evaluated along with bony nasal septal deviation (NSD) shown on the OMU CT was measured. In the frontal facial photograph, perceived overall facial asymmetry in addition to the anthropometric measurement of the each upper, middle, lower facial asymmetry was measured. Results : The incidence of nasal floor tilting (NFT) was shown as 51 % (136 in 265 patients), defined as the tilted group. The mean NFT angle in the tiled group showed 7.7°with a standard deviation (SD) of 4.4°, ranging from 2.4° to 22.4°. The tilted group showed a higher incidence of NSD, asymmetrical orbit levels, asymmetrical maxillary sinus levels along with the size (P < .001) than the non-tilted group. The perceived facial asymmetry and perceived horizontal level asymmetry of the face were associated with a higher incidence in the tilted group (P < .01), whereas the external nasal deviation and asymmetry in each upper, middle, and lower face showed no difference in between two groups. Conclusions : The tilting of the nasal floor can be seen in half of the patients complaining nasal symptoms. The incidence of asymmetry in the nasal skeleton as well as the in the face were shown to be higher in the NFT patients compared to patients not presenting a NFT. In addition, a higher nasofacial structures corresponded with the higher side of the nasal floor.