# Assessment of Paranasal Sinus Growth with 3D Volumetric Measurements and the Effect of Anatomic Variations on Sinus Volume in a Pediatric Population

## TL;DR

This study creates a sinus volume chart for children and finds that anatomical variations do not significantly affect sinus size.

## Contribution

First study to assess anatomical variations' impact on sinus volume using 3D measurements with balanced age and sex groups.

## Key findings

- No significant difference in sinus volumes between right and left sides, sexes, or presence of anatomical variations.
- Sphenoid pneumatization appeared in 30% of infants and over 75% of older children.
- Frontal pneumatization began at age 2–3 and exceeded 50% after age 4.

## Abstract

This study is the first article to investigate the impact of anatomical variations on sinus development and volume by 3D segmentations, along with the age at which variations emerge, with a balanced distribution of age and sex. Our volume calculations showed no significant difference between right and left paranasal sinus volumes, between sexes or regarding presence or absence of sinonasal variations. Therefore, we developed a paranasal sinus volume chart suitable for routine practice. Since anatomical variations had no significant impact on the volumes, we believe this chart can be used in all cases.

Background: We aimed to determine paranasal sinus volumes using 3D volumetric measurements and to evaluate the effect of anatomical variations on these volumes, ensuring balanced age and sex distribution during childhood. Methods: Thirteen age groups (0–16 years), each including 10 males and 10 females, were formed. After excluding sinus pathologies, a total of 260 subjects were randomly selected from CT head examinations. Right and left frontal, maxillary, and sphenoid sinus volumes were calculated using 3D Slicer software (version 5.6.2) following manual segmentation of axial CT slices. Also, the presence of right and left Agger Nasi cells, Haller cells, Onodi cells, and concha bullosa were recorded. Results: No significant difference was found between males and females in sinus volumes (p > 0.05). Mean right and left maxillary sinus volumes were 6.23 cm3 and 6.27 cm3 (p = 0.551); frontal sinuses were 0.79 cm3 and 0.86 cm3 (p = 0.170); and sphenoid sinuses were 1.64 cm3 and 1.85 cm3 (p = 0.041). Sphenoid sinus pneumatization appeared in 30% of the 0–6-month group and in over 75% of older groups. Frontal pneumatization began at age 2–3 and exceeded 50% after age 4. Agger Nasi, Haller, Onodi cells, and concha bullosa were detected in 58.8%, 31.2%, 10%, and 22.3% of cases, respectively. Anatomical variations showed no significant effect on sinus volumes (p > 0.05). Conclusions: We developed a paranasal sinus volume chart applicable to routine practice, showing that anatomical variations had no significant impact on the development. This is the first study to investigate the impact of anatomical variations on sinus development and volume, along with the age at which variations emerge, with a balanced distribution of age and sex.