A surgical view of the superior nasal turbinate: anatomical study.

Differences of the superior nasal turbinate (SNT), presence of the supreme nasal turbinate (SpNT) and measurements of opening sphenoid sinus (OSS) are consistent anatomical landmarks that allow for safe entrances, such as posterior ethmoidectomy and sphenoid sinusotomy. The purpose of study was to investigate the anatomical details of the SNT for approaching the OSS on 20 specimens of adult cadavers under an operating microscope. The SNT and SpNT were localized more perpendicular than parallel to their axes. The SpNT structure was observed in 12 specimens (60%) and it was classified into three types. Type A SpNT was shortest of all turbinates (58.3%). In types B and C, SpNT was equal or larger than the SNT. These types were seen in 41.7% of specimens. In 11 specimens, posterior ethmoidal cells opened to supreme nasal meatus. In 7 specimens, there was one opening to supreme nasal meatus, while 2 openings were detected in 12 specimens, and 3 openings were seen in 1 specimen. All these openings belonged to posterior ethmoidal cells. To determine the position of the OSS, distances between some anatomical points were measured. In cases where the SpNT is present or the SpNT is bigger than the SNT, it is certain that a different method will be applied during the procedure in the nasal cavity. The SNT and the SpNT may easily be injured by unrecognized dissection in types B and C, leading to the disruption of its olfactory neuroepithelium and possibly to postoperative hyposmia.