Ostium maxillare accessorium - a morphologic study

Abstract

Abstract Background and aims : The "Osteomeatal complex" of the middle meatus contains the primary maxillary opening as well as in few cases the 'accessory maxillary ostia'. An ostium leading to maxillary sinus apart from the primary maxillary opening is defined as accessory maxillary ostia. Location of accessory maxillary ostia is more advantageous than primary maxillary opening. Accessory maxillary ostia can be utilized to approach the maxillary sinus in cases of difficulty in approaching the primary maxillary opening. The present study was undertaken to study the morphological variations of accessory maxillary ostia in human cadavers. Material and methods : Forty two sagittal sections of the human cadavers were studied for the incidence, location, number, shape, size and laterality of accessory maxillary ostia. Results : Accessory maxillary ostia were found in 26% of the specimens. Of these 55.54% were found in anterior fontanelle and 45.45% in the posterior fontanelle. Shape varied from oval to round and dimensions 1.33 to 5.6mm antero-posteriorly and 1.07 to 2.55mm vertically. Accessory maxillary ostia were frequently observed unilaterally. Conclusion : Accessory maxillary ostia when present can be utilized during clinical procedures to get access to maxillary sinus in cases of difficulty in approach due to the variation in configuration of uncinate process or bulla ethmoidalis. Morphology of accessory maxillary ostia can thus be a valuable source of information to the endoscopic surgeons operating on the maxillary sinus.