Transnasal endoscopic medial maxillary sinus wall transposition with preservation of structures.

OBJECTIVES/HYPOTHESIS: To evaluate the increase in access to the maxillary sinus (MS) with transnasal endoscopic medial maxillary sinus wall transposition (TEMMT), while preserving major structures of the nasal cavity. STUDY DESIGN: The study was divided into three parts: anatomical, radiographic, and case series. METHODS: Three cadaveric dissections (total of six sides) confirmed the feasibility of the TEMMT approach. Radiographic measurements using maxillofacial computed tomography scans were taken to assess the maximal antrostomy. The TEMMT approach was performed on six consecutive patients with benign MS disease. RESULTS: The cadaveric measurements were consistent with the radiographic measurements, which confirmed the maximum access to the MS. The radiographic measurements ranged from 14.4 to 39.1 mm in the anteroposterior dimension, 8.2 to 23.7 mm in the superior-inferior dimension, and 36° to 98° in the angle between the medial and anterior wall of the MS. In the patient series, five patients presented with an odontogenic cyst, and one patient had an antrochoanal polyp in the MS. The TEMMT approach provided excellent access and adequate resection, as well as preservation of the nasolacrimal duct and inferior turbinate. Finally, the mucosal flap was sufficient to cover the inferior meatal antrostomy. CONCLUSIONS: TEMMT provides excellent access into the MS, especially the floor and anterior wall, without the morbidities of the Caldwell-Luc or medial maxillectomy approach. In addition, the transposition of the inferior turbinate and the mucosal flap provides coverage of the medial wall with preservation of the inferior meatus, inferior turbinate, and nasolacrimal duct for patients with benign MS disease. LEVEL OF EVIDENCE: NA Laryngoscope, 126:1504-1509, 2016.

Endoscopic endonasal approach to the infraorbital nerve with nasolacrimal duct preservation.

Objectives Infraorbital nerve (ION) decompression, excision to remove intrinsic tumors, and resection with oncological margins in malignancies with perineural invasion or dissemination are usually accomplished with an open approach. The objective is to describe the surgical anatomy, technique, and indications of the endonasal endoscopic approach (EEA) to the ION with nasolacrimal duct preservation. Design Eleven sides of formalin-fixed specimens were dissected. An anterior maxillary antrostomy was performed. The length of the ION prominence within the sinus and anatomic features of the covering bone were studied. A 45-degree endoscope visualized the infraorbital prominence endonasally. An angled dissector and dural blade allowed for dissection and resection of the ION ipsilaterally and contralaterally. Results The bone features of the ION prominence allowed for ipsilateral dissection in 10 out of 11 sides. In one case with the ION surrounded by thick cortical bone, the dissection could only be started by drilling contralaterally. The 45-degree endoscope visualized 92.2% and 100% of the length of the nerve using the ipsilateral and contralateral nostrils, respectively. Ipsilaterally, 83% of its length was resected, and 96.3% was resected contralaterally. Conclusion The ION can be approached using an ipsilateral EEA with nasolacrimal duct preservation in most cases. The contralateral approach provides a wider angle to access the ION. This technique is primarily indicated in cases where the EEA can be used for tumor resection and oncological margins within the ION.