Endoscopic Visualization of the True Maxillary Ostium Following Uncinectomy

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

OBJECTIVES

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:3285-3291, 2023.

The Use of 0° and 70° Endoscopes in Maxillary Antrostomy

BACKGROUND AND OBJECTIVES

Performing an effective maxillary antrostomy is critical to improving chronic maxillary sinusitis symptomatology. Incomplete dissection of the uncinate process and failure to incorporate the natural drainage pathway may lead to recirculation and need for revision surgery. The purpose of this study is to determine if 70° endoscopes provide added value in determining incomplete dissection or residual disease.

METHODS

Prospective study of 35 sinuses from 18 patients undergoing FESS for Chronic Rhinosinusitis (CRS) between 11/1/2020 and 4/30/2021. Two fellowship trained Rhinologists initially performed maxillary antrostomies exclusively using a 0° endoscope, then transitioned to a 70° endoscope. Surgeons completed a survey to assess completion of the antrostomy prior to use of 70° endoscope, sino-nasal anatomy, and difficulty of the operation. Intraoperative photographs before and after using a 70° endoscope were evaluated by a third party. Pre-operative CT scans were used to evaluate the sphenoid keel-caudal septum-nasolacrimal duct (SK-CS-NL) angle.

RESULTS

Of 35 sinuses from 18 patients all 35 sinuses had CRS with 48.5% having nasal polyposis and 42.9% having active infection. There was residual inflammatory tissue in the anterior maxillary sinus, including polypoid tissue and uncinate process prior to using the 70° endoscope in 82.9% of sinuses. The natural drainage pathway was not incorporated into the dissection in 28.6% of sinuses before converting to 70° endoscope. Incomplete dissection with 0° endoscope was not associated with nasal polyposis (P = .086) or uncinate position (0.741). Narrow SK-CS-NL angles were associated with incomplete dissection of the anterior maxillary sinus with 0° endoscope (16.0° ± 3.0° vs 20.6° ± 3.2°; P = .013).

CONCLUSION

Use of 70° endoscope in maxillary antrostomy may be beneficial in identifying and resecting disease within the anterior maxillary sinus that may otherwise be difficult to find using a 0° endoscope. This is especially true in patients with narrow nasolacrimal duct positioning.

[Surgical anatomy of the maxillary sinus]

BACKGROUND

Improved understanding of the microanatomy of the paranasal sinuses, including its individual variations, makes a substantial contribution to current progress in endonasal endoscopic microsurgery. Microanatomy of the sinuses is an active field of present scientific investitations.

MATERIALS AND METHODS

A comprehensive review on microanatomy of the maxillary sinus is presented from the perspective of contemporary endonasal endoscopic microsurgery.

RESULTS

The range of variation of the individual microanatomy of all sections of the maxillary sinus is presented, in particular to minimize secondary sugical tissue trauma, to avoid complications (e.g. on orbital tissues) and as a basis for the prelacrimal access to the maxillary sinus.

CONCLUSION

Improved understanding of the range of microanatomical variations reduced the burden on the patient while opimizing the effectiveness of the necessary surgical manipulations.