Sexual dimorphism of maxillary sinuses in children and adolescents - A retrospective CT study.

Background: In the postnatal period, some sexual dimorphism is observed from the moment of birth, but it is most pronounced from puberty. The aim of the study based on CT images was to assess possible sexual dimorphism of the maxillary sinus in children aged 0-18.

Methods: The retrospective analysis of CT images of the head (assessed as normal by radiologists) of 170 patients aged 0-18 (85 females and 85 males) was performed. The maxillary sinuses of every patient were bilaterally measured in three planes. Three diameters were obtained: maximum transverse (horizontal) diameter (the maxillary sinus width, MSW); maximum vertical diameter (the maxillary sinus height, MSH) and maximum antero-posterior diameter (maxillary sinus length, MSL). The automatic CT image segmentation algorithm was used (Syngo Via for Oncology, Siemens) to establish maxilla retrospective analysis of CT images of the head (assessed as normal by radiologists) of 170 patients aged 0-18 (85 females and 85 males) was performed. The maxillary sinuses of every patient were bilaterally measured in three planes. Three diameters were obtained: maximum transverse (horizontal) diameter (the maxillary sinus width, MSW); maximum vertical diameter (the maxillary sinus height, MSH) and maximum antero-posterior diameter (maxillary sinus length, MSL). The automatic CT image segmentation algorithm was used (Syngo Via for Oncology, Siemens) to establish maxillary sinus volume (MSV). The coefficient of variation used in the study allowed the biological variation between sexes to be observed.

Results And Conclusions: The sexual dimorphism of maxillary sinus parameters is variable and depends on the phase of ontogenesis. All investigated parameters of maxillary sinuses are larger in males at 2-3 years (except for the length, which is larger in females by the end of three years, between six and nine years and after 15 years). The sexual dimorphism is less evident during the first year of age, and the most evident between 15 and 16 years. During the first two years, females are dominant with all parameters being larger than in males. The maxillary sinus length is developmentally the most stable parameter of maxillary sinuses, because throughout the investigated ontogenesis, the sexual differences are very similar. The most evident sexual dimorphism is observed in the volume of the maxillary sinus.