ABSTRACT
OBJECTIVE@#To evaluate the relation between the incidence of sinusitis and the position of the inferior border of the middle concha related to the semilunar hiatus.@*METHOD@#Clinical data of 94 cases (185 sides of paranasal sinus) diagnosed by CT detection, operative findings and clinical features were analyzed. The middle concha was divided into 3 types according the position of its inferior border related to the semilunar hiatus: superior hiatus type (the inferior border of the middle concha superior to the semilunar hiatus), hiatus type (the inferior edge of the middle concha at the level of the semilunar hiatus) and inferior hiatus type (the inferior edge of the middle concha inferior to the semilunar hiatus). Statistic analysis were taken for comparing the incidence of sinusitis among the position of the middle concha and other anatomical variations such as deviation of nasal septum, pneumatization of middle concha, paradoxical curve of the middle concha, variations of the uncinate process, ethmoidal bulla enlargements, Haller cells and agger cell pneumatization.@*RESULT@#There was no significant difference of the anatomic variations by comparing the superior hiatus type together with the hiatus type versus the inferior hiatus type (P > 0.05). But the incidence of sinusitis in each type was remarkably different, the superior hiatus type and hiatus type had more sinusitis than the inferior hiatus type. Furthermore, the second and third type of sinusitis in the superior hiatus type and hiatus type weighted over the inferior hiatus type (P 0.05).@*CONCLUSION@#There is no association between the position of the middle concha and the anatomic variations of the nasal cavity and paranasal sinus. The poorly developed middle concha may acts as a risk factor for sinusitis and nasal polyps.