Comparison of Two Methods for Assessing the Maxillary Sinus Volume in Patients with and Without Unilateral Cleft Lip and Palate: A Retrospective Cross-Sectional Study

<b>Background/Objectives</b>: The aim of this study was to compare two methods for maxillary sinus volume measurement, assessing their accuracy. The analysis compared the maxillary sinus volume in patients with unilateral cleft lip and palate (UCLP) and in a non-cleft group, using a manual method and a three-dimensional (3D) semi-automated segmentation method. <b>Methods</b>: The research was conducted according to the STROBE guidelines. Sixty patients were included in this study: thirty patients with UCLP were in the research group, and the control group consisted of 30 patients with no craniofacial deformities. Cone-beam computed tomography (CBCT) was analyzed. The manual maxillary sinus volume was calculated based on its approximation to two geometric shapes based on mathematical formulas using linear measurements that were performed on all sinus CBCT scans in the maximum diameter in three planes. The semi-automatic segmentation method using ITK-SNAP 3D-imaging software version 4.2.2 was used to automatically calculate the maxillary sinus volume of the sinuses. The manually calculated volume was compared with the automatically calculated one, and statistical analysis was performed. <b>Results</b>: The cleft group presented lower values in both the automatic and manually calculated volumes for both the right (automatic: <i>p</i> = 0.49; manual <i>p</i> = 0.009) and left (automatic: <i>p</i> = 0.46; manual <i>p</i> = 0.11) maxillary sinuses than the non-cleft group. The cleft group presented statistically significant higher discrepancies in values between the manual and semi-automatic method than the control group (RMSV <i>p</i> = 0.0011; LMSV <i>p</i> = 0.033; TMSV <i>p</i> = 0.003). <b>Conclusions</b>: The manual method may not reveal the exact anatomical topography of the maxillary sinuses. In UCLP patients, the maxillary sinus anatomy may be more complex. Therefore, a semi-automated method may be more advisable to preserve the accuracy of the measurements.