Extracranial Facial Nerve Schwannoma—Histological Surprise or Therapeutic Planning?

Abstract

Schwannomas (neurilemomas) are benign, slow-growing, encapsulated, white, yellow, or pink tumors originating in Schwann cells in the sheaths of cranial nerves or myelinated peripheral nerves. Facial nerve schwannomas (FNS) can form anywhere along the course of the nerve, from the pontocerebellar angle to the terminal branches of the facial nerve. In this article, we propose a review of the specialized literature regarding the diagnostic and therapeutic management of schwannomas of the extracranial segment of the facial nerve, also presenting our experience in this type of rare neurogenic tumor. The clinical exam reveals pretragial swelling or retromandibular swelling, the extrinsic compression of the lateral oropharyngeal wall like a parapharyngeal tumor. The function of the facial nerve is generally preserved due to the eccentric growth of the tumor pushing on the nerve fibers, and the incidence of peripheral facial paralysis in FNSs is described in 20–27% of cases. Magnetic Resonance Imaging (MRI) examination is the gold standard and describes a mass with iso signal to muscle on T1 and hyper signal to muscle on T2 and a characteristic “darts sign.” The most practical differential diagnoses are pleomorphic adenoma of the parotid gland and glossopharyngeal schwannoma. The surgical approach to FNSs requires an experienced surgeon, and radical ablation by extracapsular dissection with preservation of the facial nerve is the gold standard for the cure. The patient’s informed consent is important regarding the diagnosis of schwannoma and the possibility of facial nerve resection with reconstruction. Frozen section intraoperative examination is necessary to rule out malignancy or when sectioning of the facial nerve fibers is necessary. Alternative therapeutic strategies are imaging monitoring or stereotactic radiosurgery. The main factors which are considered during the management are the extension of the tumor, the presence or not of facial palsy, the experience of the surgeon, and the patient’s options.

Effects of Intradermal Therapy (Mesotherapy) on Bilateral Cervicobrachial Pain

“…Somatic structures include the neck muscles, zygapophyseal joint, and intervertebral discs. The nerve root or trunk is often the cause of radiating arm pain, and since one in four schwannomas originate in the nerve structures of the head and neck, it can also be a symptom of more serious pathologies for which it is necessary to make a differential diagnosis [27].…”

Late-Onset Type 1 Diabetes Mellitus and Unexplained Subcutaneous Lesions

“…Given the rapid onset of the patient's swelling, malignant lesions were considered more likely than benign lesions. Grossly, nodular fasciitis may be soft and gelatinous in consistency, similar to a myxoma or a benign peripheral nerve sheath tumor [13]. When more collagenous and firm, it may resemble fibromatosis, a locally recurring, non-metastasizing proliferation of fibrous tissue.…”

Lateral Spread Response: Unveiling the Smoking Gun for Cured Hemifacial Spasm

“…This discrepancy may be attributed to the propensity of facial nerve schwannomas to originate, predominantly, from the peripheral aspect of the facial nerve rather than from its Life 2023, 13, 1825 9 of 12 intracranial segment. Consequently, the presence of abnormal electrophysiological signs such as LSR are not evident in such cases [32].…”