Feijão, Moisés Ximenes

AbstractObjectiveDescribe a reliable anatomical landmark that can be used to locate the maxillary sinus natural ostium (MSNO) during endoscopic surgery, even if the uncinate process is preserved.DesignDescriptive anatomical.SettingAn anatomical and radiological study was performed to evaluate the consistency of the landmark, denominated "M" line.Subjects and MethodsDissections were performed in 57 cadaver heads (114 sides). In addition, 73 computerised tomography (CT) scans (146 sides) of patients with chronic inflammatory sinonasal disease were analysed using a three‐dimensional (3D) reconstruction computer program.ResultsThe "M" line crossed the MSNO in 112 dissected sides (98.2%) and 140 sides at CT 3D reconstruction (95.9%).ConclusionThe "M" line is a reliable anatomical landmark for predicting MSNO location. As such, it could improve and facilitate endoscopic sinus surgery, using traditional, minimally invasive or uncinate preserving techniques.