Background. The widespread use of functional endoscopic intervention in the nasal cavity requires detailed knowledge of the variant anatomy of the structures of the paranasal sinuses, taking into account age and gender, necessary to improve surgical treatment. In order to determine the variants of the structure of the anastomosis and intra-sinus septa of the maxillary sinus in childhood, a study was conducted of 425 computed tomograms of the heads of children aged 1 to 21 years of both sexes without pathology of the paranasal sinuses. Results and conclusions. It has been established that, regardless of gender, the width of the anastomosis of the maxillary sinus increases in each subsequent age group, with the largest increase at 2–3 years and 8–12 years and has no bilateral or gender differences. Intra- sinus bone septa in the first and second childhood ages were determined only in girls. In adolescence and adolescence - in persons of both sexes, and the frequency of occurrence increases with age in boys and young men. In the right maxillary sinus, incomplete and complete septa were identified, in the left - only incomplete. The greatest number of septa was observed in adolescence on the right. Intra-sinus septa can divide the sinus into two or more chambers of varying sizes, which remain connected to each other, creating difficulties during surgery. Thus, variants of the anatomical structure of the intra- sinus septa in children have been identified, associated with gender, age and side of the skull, while the variability of the width of the anastomosis depends only on age.

The aim of the study was to describe morphometric characteristics of the posterior parts of the nasal cavity in different periods of childhood and to specify the age-related norm for improving surgical treatment options of choanal atresia and providing an optimal access to the anterior part of the skull base. Material and methods. The study included 87 children aged 1-21 who were exposed to craniometry of the nasal cavity structures. Results. The age-related variability of the linear dimensions and shape of the choanae, their relationship with the dimensions of the pyriform aperture and the height of the nasal cavity in the posterior part were defined in the study. The increase in the height of the choanae and the height of the nasal cavity at the back starts from 2– 3 years of age, and the width – from 8–12 years of age. The height and width of the pyriform aperture are equal to the age of 8–12; these parameters increase in older children's groups with a predominance of the height over the width. The height of the nasal cavity at the back increases in all age periods. The growth of the studied structures of the nasal cavity is completed by adolescence. In infancy, the height of the choanae is less than the height of the nasal cavity at the back by 45%, and less than the height of the pyriform aperture by 20%; in adolescence, these ratios are 42% and 23%, respectively. In infancy the choanal width is less than the width of the pyriform aperture by 49%, and in adolescence – by 40%. In infancy and early childhood, the choanae are typically small in height and width. Their shape is round in 25% of cases, however, ovoid shape is also found. The height and width of the pyriform-shaped aperture at these age periods are similar and do not exceed 17–18 mm; the height of the nasal cavity at the back is 25–27 mm. Conclusion. The authors have described age-related morphometric features of the posterior structures of the nasal cavity. These features should be taken into account by otorhinolaryngologists and neurosurgeons when planning endoscopic intranasal surgical access in children. The younger the child is, the more difficult it is to perform a surgery due to the significant restriction of the access resulted from the small size of the piriform opening and the nasal cavity, and the obstinacy of the nasal septum. When performing choanotomy for atresia, it is necessary to form the choana comparing it in shape and size with the age-related norm

Background. The aim of the study was to determine criteria variability of nasal septum bone in different periods of childhood for its application in practical otorhinolaryngology. Material and methods. Cephalometry of 65 intact specimens of child’s craniums without sex identity and statistical analysis of the obtained data were made. Results. The periods of intensive and deterred growth of nasal septum bone criteria were determined in definite age groups of children. The reliability is achieved by the age of 16. The detection frequency of its deviation is increasing with aging. Conclusions. The obtained data can be used for optimization of rhinosurgery in children.

The morphotopometric variability of the ethmoidal labyrinth and the parameters of the nasal cavity for 87 childrens cranium (121 years) has been determined. The growth of the ethmoidal labyrinth and the nasal cavity occurs undulating and unevenly. The increase of the height of the ethmoidal labyrinth begins earlier than its width and length from 23 years to 1316 years old. Growth periods the height of ethmoidal labyrinth occur for 23 years, 812 and 1316 years; widths 47, 812 and 1721 years; length 47, 812 and 1316 years. At the ethmoidotomy in the infant and early childhood, the smallest size of the ethmoidal labyrinth should be taken into account: width 78 mm, height 1416 mm, length 2729 mm, so in these age periods there is a high risk of damage of the cribriform and orbital plates ethmoid bone with the development of iatrogenic complications. The nasal cavity штchildren expands posteriorly as well as in adults. In the infancy, the width of the nasal cavity at the back corresponds to the width in the front section, from 2 years prevails than in front and by adolescence becomes larger for 33,5 mm. Knowing these agerelated features of the structure of the childrens nasal cavity, during surgery the rhinosurgeon when shifting the middle nasal shells medially or laterally should ensure to maintain the physiological model of the nasal cavity. In infancy, the width of the ethmoidal labyrinth is larger than the width of the nasal cavity by 38,5%, and by adolescence this ratio increases to 76,8%. The length of the nasal cavity increases from 47 years to adolescence, the length of the ethmoidal labyrinth grows parallel to the maximum length of the nasal cavity and it is less for more than a half in all childrens age groups: in the infancy by 74%, in adolescence by 85.1%. The height of the nasal cavity is twice the height of the labyrinth in any childhood age, the distance from the bottom of the nasal cavity to the lower edge of the middle nasal shell must be correlated with the distance above the level of the average nasal shell during intranasal surgeries and do not exceed it for the introduction of tools.