Anatomical Variation in the Drainage Pattern of Frontal Sinus – A Cadaveric Study

Background A proper and detailed knowledge about the frontal sinus drainage pathway is essential for the radiologist to interpret the computed tomography scan of the paranasal air sinuses to find out normal and variant in the anatomy of frontal sinus ostium, and also for the surgeons to do endonasal sinus surgery particularly in the frontal sinus area with enough confidence and to give good postoperative result. With this background, the present study was focused to study the variation in the drainage pattern of frontal sinus in relation to uncinate process in cadaveric specimens. Materials and Methods The midsagittal section of head and neck portion of 40 cadaveric specimens with intact frontal sinus and frontal sinus drainage pattern were selected. By careful dissection, pattern of frontal sinus drainage was identified and pattern of drainage of frontal sinus in relation with uncinate process was studied. Result Frontal sinus drainage pattern is anteromedial to uncinate process (Type 1) in 28 specimens (70%) and posterolateral to uncinate process (Type 2) in 12 specimens (30%). Conclusion The results of our study show that the frontal sinus drainage pattern is more commonly present anteromedial to uncinate process compared with posterolateral position. This variation in the drainage pattern of frontal sinus should be kept in mind by the radiologist to give proper radiological interpretation and by the surgeons to avoid intraoperative complications and also to give good postoperative result.