Background: The anatomy of the paranasal sinus is significantly different between adults and children, and surgeons must be aware of these differences to safely perform pediatric functional endoscopic sinus surgery. The purpose of this study was to determine the normal dimensions of the paranasal sinuses during development using magnetic resonance imaging (MRI) data compiled from the largest cohort to date.
Methods: The records of 2025 children, aged 0-18 years, who underwent cranial MRI, were examined retrospectively and 1452 patients with no history of sinus disease were included in the study. Coronal, axial, and sagittal images were used to measure the dimensions of the frontal, maxillary, ethmoid, and sphenoid sinuses, and the sinus volume index was measured. Patients were divided into 10 cohorts based on their age at the time of the scan.
Results: No difference between left and right one-dimensional measurements and volume indexes for the maxillary, sphenoid, ethmoid, and frontal sinuses was observed in any age group. Initial signs of pneumatization were observed at birth for the maxillary and ethmoid sinuses, at 9 months for sphenoid sinus, and after the age of 5 years for the frontal sinus.
Conclusion: These results will help physicians correlate the clinical and radiographic findings of pediatric patients who are being evaluated for sinus disease and potential surgical intervention. Knowledge of the variations in the size of the paranasal sinuses is essential for determining the significance of incidental findings.