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How To: Tension-Free Anterior Rerouting of the Facial Nerve in Management of Jugular Foramen Paragangliomas

by Dedi Kong, MD, Yibo Zhang, MD, PhD, Feitian Li, MD, PhD, Wei Li, MD, PhD, and Chunfu Dai, MD, PhD •

Introduction

Jugular foramen paragangliomas (JFPs) are highly vascularized tumors. Although JFPs grow slowly and are considered histologically benign, the infiltrative nature of these tumors tends to destroy vital neurovascularities adjacent to the tumor. Since the infratemporal fossa type A approach (IFTA-A) was developed by Ugo Fisch, MD, the IFTA-A with total anterior transposition of the facial nerve (FN) and high cervical exposure has been the standard surgical procedure for removing JFPs (J Laryngol Otol. 1978;92:949-967). Traditionally, during anterior FN translocation, the FN was dissected from the geniculate ganglion to the main trunk of FN in the parotid gland to achieve permanent translocation; this procedure sacrificed the blood supply of the FN from the stylomastoid and deep petrous arteries, with a postoperative FN function (H-B I–II) of 67.2% (J Laryngol Otol. 2016;130:219-224). To preserve more feeding arteries of the FN, Dr. Brackmann (Otolaryngol Head Neck Surg. 1987;97:15-17) dissected the FN, the posterior digastric muscle, and soft tissues around the stylomastoid foramen anteriorly. Postoperatively, preserved FN function (H-B I–II) was noted in 73% of patients. However, it is still challenging to consistently achieve tension-free total FN anterior rerouting while applying Dr. Brackmann’s technique.

In the present study, we modified Dr. Brackmann’s total anterior FN rerouting technique to achieve tension-free FN anterior transposition and explored the surgical outcomes postoperatively.

Method

We conducted a retrospective review of the clinical data of patients with JFPs who underwent surgical management via the IFTA-A with tension-free FN anterior transposition at the otology and skull base surgery department of Fudan University in Shanghai, China, between April 2013 and September 2019. Only patients with JFPs who had normal FN function preoperatively according to the House-Brackmann (HB) grading system were included. This study was approved by the institutional review board of Fudan University.

We modified Dr. Brackmann’s total anterior FN rerouting technique to achieve tension-free FN anterior transposition and explored the surgical outcomes postoperatively.

All patients underwent temporal bone high-resolution computed tomography and magnetic resonance imaging (MRI) with gadolinium enhancement, magnetic resonance arteriography, and magnetic resonance venography. Digital subtraction angiography with super-selective endovascular embolization was performed 48 hours prior to surgery. Tumors were classified based on the Fisch classification system. The first follow-up of temporal bone MRI with enhancement was conducted three months postoperatively. Subsequently, the patients were evaluated every 12 months. Gross total resection (GTR) was defined as complete tumor excision without residue on temporal bone MRI. Tumor recurrence was defined as the occurrence of a new contrast-enhanced lesion in situ following GTR.

Surgical Procedures. The standard IFTA-A was applied in all patients, and several modifications were made to reduce FN tension during total anterior transposition (Figure 1; supporting video):

  1. The FN was dissected from the genicular ganglion to the stylomastoid foramen, the digastric muscle was detached from the digastric ridge, and the FN was dissected from the stylomastoid foramen and further dissected to the surface of the styloid process. Then the FN, the digastric muscle, and the parotid gland were anteriorly displaced (the main trunk of the FN in the parotid gland was not dissected). The parotid gland was sutured tightly to the lower margin of the temporal muscle to shorten the distance from the geniculate ganglion to the main trunk of the FN in the parotid gland.
  2. A long articulated retractor was placed at an angle of 45° to push the posterior belly of the digastric muscle and the parotid gland anteriorly and superiorly to further minimize the distance from the genicular ganglion to the main trunk of the FN in the parotid gland.

Statistical Analysis. Continuous variables are presented as medians and ranges, and categorical variables are presented as frequencies and percentages.

Results