The Transverse Turbinate Line: A Reliable Landmark for the Maxillary Sinus Natural Ostium.

Abstract

Approximating the maxillary sinus natural ostium's (MSNO) natural position during anterograde surgery is challenging, as only a single visual "landmark," the maxillary line, is routinely offered to guide the identification of the MSNO in three-dimensional space. Despite almost 40 years of endoscopic sinus surgery (ESS) experience in North America, maxillary recirculation and discontinuity between the natural and surgical ostia are commonly encountered during revision ESS. Consequently, we feel an additional visual landmark would assist in localizing the MSNO with or without image guidance. In this study, we aim to provide a second reliable landmark in the sinonasal cavity. We present a cadaveric anatomical landmark series that provides a second visual landmark for the MSNO, which we have labeled the transverse turbinate line (TTL): a 2-millimeter zone of confidence for the craniocaudal positioning of the MSNO that can be combined with the anteroposterior (AP) landmark of the maxillary line. In our study, 40 cadaveric sinuses were dissected, and the TTL was found to correspond consistently with the zone between the superior and inferior aspects of the MSNO. We anticipate that this second relational landmark may decrease the time required for anterograde access to the MSNO in trainees, increase the accuracy of identification, and translate to lower long-term recirculation and maxillary surgery failure rates. NA Laryngoscope, 133:3285-3291, 2023.