Endoscopic transoral nasopharyngectomy

ICA Window: A Reliable Landmark for Locating Parapharyngeal ICA via Endoscopic Transoral Medial Pterygomandibular Fold Approach

OBJECTIVE

One of the primary challenges in surgical procedures involving parapharyngeal space (PPS) lesions is accurately localizing the internal carotid artery (ICA) within the parapharyngeal space. This study aims to investigate the anatomical landmarks of the parapharyngeal internal carotid artery (ppICA) in endoscopic transoral approach surgery.

METHODS

A total of seven fresh frozen cadaveric heads (14 sides) were dissected using the endoscopic transoral medial pterygomandibular fold approach in the anatomical laboratory of the Surgical Treatment Technology Innovation Unit at Nasal Skull Base Tumor in Eye and ENT Hospital, Fudan University. Additionally, a comparative anatomical study was conducted on three cadaveric head specimens using the microscopic preauricular infratemporal approach. Photographic documentation and measurements were taken for adjacent structures of the ppICA, along with specific anatomical structures neighboring the ppICA. To illustrate the method for locating and protecting the ppICA, three cases involving the prestyloid, poststyloid, and retropharyngeal spaces were selected.

RESULTS

The stylopharyngeal muscle was located anterolaterally to the ppICA, while the levator veli palatini and longus capitis muscles were situated anterosuperiorly and posteromedially to the ppICA, respectively. The area enclosed by these three muscles was named the "ICA window" in this study. The ppICA was posterior to this window, sealed by the stylopharyngeal fascia. This ICA window was considered a reliable landmark for identification of the ppICA via endoscopic transoral medial pterygomandibular fold approach for PPS surgery.

CONCLUSION

The ICA window, delineated by the stylopharyngeal muscle, tensor veli palatini muscle, longus capitis muscle, vaginal process of the tympanic bone, and the intervening fascial structures, emerges as a reliable anatomical landmark for orienting the ppICA during endoscopic transoral surgery for parapharyngeal space procedures.

LEVEL OF EVIDENCE

N/A.

The Use of Water Sac Dilation in Resecting Parapharyngeal Space Benign Tumor via Transoral Approach

OBJECTIVES

To evaluate the effectiveness of employing the water sac dilation (WSD) method during endoscopy-assisted transoral resection of parapharyngeal space benign tumor (PSBT).

METHODS

Between February 2017 and January 2022, a total of 32 patients diagnosed with PSBT were included in this prospective study and were randomly allocated into two groups: the WSD group and the control group. Tumors of the WSD group patients were all dissected using the WSD method.

RESULTS

The final numbers of studied patients in WSD group and control group were 17 and 15, respectively. The basic information was comparable between these two groups of patients. All these patients successfully underwent tumor resection via transoral approach. The operation time, intraoperative blood loss, drainage volume on the first postoperative day, drainage duration, and the total drainage volume in the WSD group patients were significantly lower than those in the control group patients (all p < 0.05). No surgical complications occurred, and no residual tumor or recurrence could be identified at 6 months after surgery in both groups of patients.

CONCLUSION

The application of the WSD method in endoscopy-assisted transoral resection of PSBT effectively attenuated intraoperative injury, improved surgical efficiency, and accelerated postoperative recovery.

LEVEL OF EVIDENCE

3 Laryngoscope, 135:665-670, 2025.

The Role of the Transeptal Window in Endoscopic Endonasal Access to the Contralateral Orbit

Objective  This study aimed to objectively compare maneuverability at the contralateral medial orbit when approached through the traditional endoscopic endonasal approach (EEA) and EEA with transeptal window (TW). Study Design  Anatomic dissections were performed bilaterally on three latex-injected cadaveric heads.  Approaches were performed sequentially; initially, an EEA was fashioned. Binostril access was achieved through a 2-cm posterior septectomy. The second stage pertained to the TW dissection. Area of exposure (AoE), surgical freedom (SF), and angles of attack (AoA) were measured along the contralateral medial orbital wall and compared for each approach. Additionally, the study presents an illustrative case describing the application of the EEA + TW for resection of an intraorbital schwannoma. Results  Compared with EEA, EEA + TW yielded a significantly greater AoE along the contralateral medial orbital wall (39.45 vs. 48.45 cm 2 , respectively; p  = 0.002). SF was statistically different between the EEA and EEA + TW (1153.25 vs. 2256.33 cm 2 , respectively; p  = 0.002). AoA in the horizontal plane were significantly broader with the EEA + TW (6.36 vs. 4.9 degrees by EEA; p  = 0.015). A 50-year-old male with a right medial extraconal orbital tumor was successfully treated through an EEA using the transeptal corridor to access the medial orbital region. No long-term complications were encountered after 31 months of follow-up. Conclusion  EEA + TW is a minimally invasive technique that maximizes exposure and maneuverability within the medial orbital wall, allowing resection of lesions that extend anteriorly. EEA + TW limits disruption of the nasal septum and overcomes the obstacle that intranasal anatomy represents for instrumentation.

Endoscopic endonasal combined transoral medial approach to the nasopharynx, parapharyngeal space, and jugular foramen

OBJECTIVE

This study aimed to validate the feasibility of an endoscopic endonasal combined transoral medial approach for treating lesions in the nasopharynx, parapharyngeal space (PPS), and jugular foramen.

METHODS

Anatomical and imaging information of six patients who underwent surgery via this approach were reviewed and analyzed.

RESULTS

The feasibility and advantages of the endoscopic endonasal combined transoral medial approach, which uses an inside-to-outside medial surgical corridor, were identified. Total resection was achieved in 3 cases with benign tumors. Safe resection margins were obtained in 2 cases with recurrent nasopharyngeal carcinoma (NPC). Pathological biopsy of NPC lesion between the Eustachian tube and arterial sheath was achieved. The internal carotid artery (ICA) was accurately located and protected in all cases and no complications occurred.

CONCLUSION

Lesions in the nasopharynx, PPS, and jugular foramen can be directly assessed via this approach. The ICA can be well identified during the surgery.

Exploration of anatomical landmarks for performing an endoscopic transoral nasopharyngectomy

BACKGROUND

Performing a nasopharyngectomy via a transoral approach has been reported; however, defining landmarks to facilitate this approach has not been addressed. This study aims to explore anatomical landmarks to aid in performing a nasopharyngectomy via the transoral corridor.

METHODS

An endoscopic transoral nasopharyngectomy was performed on six cadaveric specimens (12 sides). Related anatomical landmarks were defined, and the strategy to preserve the parapharyngeal internal carotid artery (pICA) was explored.

RESULTS

An endoscopic transoral nasopharyngectomy was successfully achieved in all 12 sides. Utilizing the pterygoid hamulus as a landmark, the cartilaginous ET and attachments could be adequately exposed. Identification of the pICA is a prerequisite prior to Eustachian tube (ET) transection. The sphenoidal spine and the petrotympanic fissure could be sufficiently revealed in all 12 sides, which aided in transection of the cartilaginous ET without pICA injury. The ET and the prevertebral contents could be adequately removed via the transoral corridor.

CONCLUSION

The pterygoid hamulus, sphenoidal spine and petrotympanic fissure serve as reliable landmarks for performing a transoral nasopharyngectomy. Identification of the pICA is a prerequisite prior to transection of the ET to avoid pICA injury.

Postoperative Pharynx and Larynx

Cancers of the pharynx and larynx are treated using a combination of chemotherapeutic, radiation, and surgical techniques, depending on the cancer type, biology, location, and stage, as well as patient and other factors. When imaging in the postsurgical setting, the knowledge of the type of tumor, preoperative appearance, and type of surgery performed is essential for accurate interpretation. Surgical anatomic changes, surgical implants/devices, and potential postsurgical complications must be differentiated from suspected recurrent tumors.