Combined Endoscopic Endonasal and Transoral Approach to Transpatial Lesion Involving the Masticator, Preparotid, and Infratemporal Spaces: A Case Study

Introduction: Transpatial lesions involving the masticator, infratemporal, and preparotid spaces are challenging both to access and to resect due to their deep location, complex anatomy, and the multitude of important neurovascular structures they may contain. Traditionally, open approaches have been used to access these formidable spaces, resulting in good visualization for complete tumor resection but poor functional and cosmetic outcomes for the patient, even with removal of benign tumors. Recently, two “closed” approaches—the endoscopic endonasal approach and the transoral approach—have garnered increasing favorability as alternative methods for accessing and resecting lesions in these spaces. The major benefit of these minimally-invasive approaches is the reduced functional and cosmetic morbidity for the patient. However, visibility and instrument maneuverability can at times be limited when one of the minimally-invasive methods is used as the sole approach for tumor resection. We present a novel technique for resection of a large masticator, infratemporal, and preparotid space tumor using a combined endoscopic endonasal and transoral approach.

Methods and Case: We report a case of a 55-year-old woman who presented with painful facial swelling and was found to have a mass involving the left masticator, infratemporal, and preparotid spaces. She was taken to the operating room by the otolaryngology and neurosurgical teams where a novel combined endonasal transpterygoid and endoscopic intraoral transmandibular approach using both straight and angled endoscopes was performed to access and resect the tumor. The post-operative course was unremarkable. Magnetic Resonance Imaging (MRI) obtained one-month post-operatively showed no residual tumor. Pathology findings revealed a mesenchymal neoplasm with chondromyxoid stroma.

Discussion: This case details a novel surgical approach that can be safely used to access and resect transpatial lesions involving the masticator, infratemporal, and/or preparotid spaces. Our combined endoscopic approach not only avoided an invasive open resection but, by employing both an endonasal and intraoral approach, was also able to achieve a wider surgical exposure than would be possible by each individual closed approach alone. Furthermore, post-surgical morbidity was reduced without compromising complete surgical removal of the tumor.

Conclusion: When appropriate, minimally-invasive endoscopic approaches should be considered for accessing deep spaces of the head and neck, as they can result in reduced morbidity for the patient with comparable tumor removal outcomes as the traditional open approaches. Two or more minimally invasive approaches can be combined to ensure sufficient surgical field visibility and adequate instrument maneuverability similar to that obtained in the traditional open approach.

No conflict of interest has been declared by the author(s).