Maxillary sinus ostium assessment: A CT study

Abstract

ObjectiveTo assess the maxillary sinus ostium (MSO) dimension and measuring the distance to nearby anatomical structures in adults using multi-slice computed tomography (MSCT). Patients and methodsParanasalCT scans of asymptomatic adults withoutparanasalsinuses or nasal pathologywere included. Axial CT with coronal reformatted imageswas donefor all subjects to get delicate details. ResultsIn 86 subjects (172 sides), the width of MSO ranged from 1 to 11 mm and distance from the MSO to the anterior maxillary wall (towardnasolacrimalduct) ranged from 7 to 25 mm. Whilethe distance fromMSO to the posterior maxillary wall (towardsphenopalatineartery) ranged from 2 to 18 mm. MSO was found above orbital floor level in 74%, at the orbital floor level in 12% and below this level in 13% of our cases. Distance from MSO to the floor of maxilla ranged from 15 to 40 mm (mean = 28.6 ± 6.7).MSOwas detectedin the posterior third of medial maxillary wall in 47%,in middle third in 32% and the anterior third in only 21%.Anteroposteriordiameter of maxillary sinus ranged from 18 to 41 mm. Its horizontal diameter ranged from 10 to 35 mm and its height ranged from 15 to 45 mm. For all measurements of the maxillary sinus and MSO, the differences between right and left side were non-significant. ConclusionThis work describes in details MSO measurements usingMSCTand measures the distance from the MSO to the beyond adjacent anatomical structures in the all directions.