A New Case of Endoscopic Resection of a Chorda Tympani Schwannoma

Abstract

Chorda tympani schwannoma is a very rare tumor, with only 12 reported cases in the English literature. There are few reports on the diagnosis of chorda tympani schwannoma, and it is easily misdiagnosed. At present, surgery is recognized as a treatment for chorda tympani schwannoma. We describe the clinical course of a patient presenting with a chorda tympani schwannoma treated with surgical resection using a transcanal endoscopic approach, and the results after this treatment were satisfactory. Therefore, we accordingly advocate the minimally invasive method of transcanal endoscopic resection to maximize intraoperative visualization and reduce postoperative morbidity for middle ear tumors.

Chorda Tympani Schwannoma: A Rare Nerve Sheath Tumor of the Middle Ear Cleft

“…Microscopic examination typically reveals a pale mass located behind the eardrum in the middle ear (2,4). Because of its rarity, chorda tympani schwannoma is often misdiagnosed (3), particularly in the early stages of growth. Radiological assessment using temporal bone CT and MRI plays a vital role in determining the location, size, and extent of the tumor (3,4).…”

“…The presentation of chorda tympani schwannoma varies, and a detailed patient history plays a crucial role in diagnosis. Hearing loss can be conductive, sensorineural, or mixed types (3). Additional reported symptoms in previous reported include tinnitus (1,3), earache (1.5), aural fullness (1), and facial palsy (1).…”

Carotid Sympathetic Plexus Schwannoma Presenting as Middle Ear and External Auditory Canal Mass

“…Schwannomas arising from the facial nerve and chorda tympani nerves present symptoms of facial palsy and dysgeusia. 4,5 The facial nerve schwannomas present expansile masses along the facial nerve canal and are mostly located in the geniculate ganglion, 6 whereas the chorda tympani nerve schwannomas are located along the course of the corresponding nerve. 5 Schwannomas arising from the Jacobson's nerve, a tympanic branch of the glossopharyngeal nerve, involve erosion of the cochlear promontory with enlargement of the inferior tympanic canaliculus.…”

“…The origins of primary schwnnoma in the middle ear from previous studies are the facial nerve, chorda tympani nerve, and Jacobson's nerve. [3][4][5] However, studies on the carotid sympathetic plexus (CSP) schwannoma in the middle ear as an origin of primary schwannoma have not yet been carried out. We describe an unusual case of primary middle ear schwannoma arising from the sympathetic plexus of the internal carotid nerve.…”

Transcanal Endoscopic Approach of a Rare Chorda Tympani Schwannoma

“…Thirteen chorda tympani schwannomas have been reported in the English literature. Only three of them have been approached endoscopically during the last 2 years (1–3). The differential diagnosis of a retrotympanic lesion should include glomus tympanicum, congenital cholesteatoma, schwannomas, adenomas, adenocarcinoma, and rhabdomyosarcoma.…”