Anatomical Variability of the Frontal Sinus in Men Based on X-Ray Computed Tomography Findings

The aim of study was to identify structural features and age-related changes in the frontal sinus in working-age men with various skull shapes.

Material and methods. Eighty computed tomograms of men aged 30–49 without pathology of the skull and paranasal sinuses were analyzed in the study. All findings were divided into two groups depending on the age of patients: group 1 consisted of 44 patients aged 30–39, and group 2 consisted of 36 patients aged 40–49. Linear measurements of the frontal sinus and its ramifications were performed in three planes (frontal, sagittal and axial); a craniotype was also determined.

Results. The results demonstrated that the mesocranial form of the skull prevailed in both age groups. When studying the septum that separated the frontal sinus, it was detected that in both studied groups there were differences in the rate of formation of the metopic suture and branches of the frontal sinus of the right and left parts of the bone. In the group of mesocranes aged 30–39 with the septum having the same direction as the sagittal suture, right half of the sinus was shorter and lower than the left one. In the group of mesocranes aged 40–49, the  above  described  features  were  absent.  The  width  of  the  right  and  left  halves  of  the  frontal  sinus  was significantly greater in the group of brachycranes aged 40–49 than in the group of brachicranes aged 30–39. However, in the frontal plane, the height of the left half of the frontal sinus was significantly higher in the group of brachycranes aged 30–39. Mesocranes aged 30–39 with sagittal position of the septum in the frontal sinus had asymmetrical ramifications of the sinus. The authors found out the tendency to the decreased number of branches of the frontal sinus and to their increased size in the mesocranes with ageing. There was observed more symmetrical position of the frontal sinus branches in the brachycranes aged 30–39. There was also found the tendency to the increased width and depth of the frontal sinus and to its decreased height on the right and on the left in the brachycranes with ageing.

Conclusion.  The  frontal  sinus  becomes  larger  but  the  number  of  its  ramifications  decreases  in mesocranes with ageing. Both halves of the frontal sinus increase in width and decrease in height, mainly on the left side in brachycranes with ageing. Regardless of the somatotype of the skull and age, there was observed a larger number of the frontal sinus ramifications on the right side; this fact may be considered a predisposing factor to the chronic frontitis and may indicate to the absence of the drainage of the frontal sinus in case of the inflammatory processes of any ethiology. The frontal bone thickens unevenly, mainly on the left side.

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