# Electromagnetic navigation-guided TOES for parapharyngeal tumors: a comparative study on precision and safety

## TL;DR

This study compares a new electromagnetic navigation-guided endoscopic surgery with traditional methods for treating tumors near the throat, finding the new method safer and more effective.

## Contribution

The study introduces and evaluates the use of electromagnetic navigation in transoral endoscopic surgery for parapharyngeal tumors.

## Key findings

- TOES + ENS showed significantly shorter surgery time, less blood loss, and faster recovery compared to traditional methods.
- The TOES + ENS group had no severe complications, while the traditional group had multiple severe events.
- TOES + ENS achieved complete tumor resection in all cases, with no recurrence during follow-up.

## Abstract

Surgical treatment of parapharyngeal space tumors using traditional methods is associated with a high risk of significant complications, and conventional open surgery has limitations in terms of visualization. This study aims to compare the safety and efficacy of transoral endoscopic surgery combined with the Electromagnetic Navigation system (TOES + ENS) with traditional surgical methods (translateral approach and TOES without ENS) in the treatment of parapharyngeal space tumors.

We conducted a retrospective comparative analysis of 41 patients diagnosed with parapharyngeal space tumors who underwent surgical resection. Patients were divided into two groups: the TOES + ENS group (T group, n = 21) and the traditional surgery group (C group, n = 20). Primary outcome measures included surgical duration, intraoperative blood loss, postoperative visual analog scale (VAS) pain scores, time to first oral intake, length of hospital stay, and the incidence and severity of postoperative complications, the latter classified using the Clavien-Dindo system.

Both groups achieved high tumor resection rates, with a complete resection rate of 100% in the T group. In the C group, one case of incomplete partial resection led to recurrence during follow-up. Compared with the C group, the T group demonstrated statistically significant advantages in all perioperative indicators: shorter surgery time (79.10 ± 22.49 min vs. 119.75 ± 17.81 min, P < 0.001), reduced intraoperative blood loss (35.43 ± 18.16 mL vs. 92.50 ± 20.93 mL, P < 0.001), lower postoperative VAS scores (2.76 ± 0.70 vs. 6.40 ± 1.10, P < 0.001), shorter time to oral intake (2.19 ± 0.40 days vs. 3.85 ± 1.42 days, P < 0.001), and shorter hospital stay (3.86 ± 1.39 days vs. 7.40 ± 1.10 days, P < 0.001). The T group recorded only one transient Clavien-Dindo Grade II complication. In contrast, the C group experienced eight complications, including four severe events: one Grade IIId (permanent nerve damage), one Grade IIIb (vascular injury requiring reoperation), and two Grade IIIa events (abscess requiring drainage).

In this study, although both surgical strategies effectively resected tumors, TOES + ENS was associated with significantly superior safety profiles, characterized by the absence of severe complications and markedly improved postoperative recovery outcomes. Despite the limitations inherent to the retrospective design and small sample size, these findings support TOES + ENS as a valuable and potentially superior surgical option compared to traditional methods for appropriately selected patients with tumors in the parapharyngeal space.

The online version contains supplementary material available at 10.1186/s12893-025-03206-y.