Facial nerve schwannoma

Aydın S., Demir M. G., Berk D., Akbulut S., Başak K., Çakıl T.

20. Rhinocamp, Muğla, Turkey, 9 - 12 May 2018, pp.18

  • Publication Type: Conference Paper / Full Text
  • City: Muğla
  • Country: Turkey
  • Page Numbers: pp.18
  • Istanbul University Affiliated: Yes

Abstract

20th Rhinocamp Meeting Proceedings

9-12 May, 2018 Marmaris • TURKEY


18


ORAL PRESENTATION 1-8

Facial Nerve Schwannoma: Case Report


Sedat Aydın1

, Mehmet Gökhan Demir2

, Derya Berk1

, Sevtap Akbulut1


, Kayhan Başak3

, Tolga Çakıl1


1

Kartal Dr.Lutfi Kirdar Education and Research Hospital, ENT Department,Istanbul 2

Etimesgut State Hospital, ENT department, Ankara 3

Kartal Dr.Lutfi Kirdar Education and Research Hospital, Pathology Department, Istanbul


Abstract: Facial nerve schwannoma is a rare benign tumor of the temporal bone. It mıght cause hearing loss, facial nerve paresis

or paralyses. We present a forty-six years old male patient who diagnosed facial nerve schwannoma on the timpanic segment.

We have operated the patient via transmastoid approach successfully. On the follow up the patients facial paralyses is not

recovered so upper eyelid implant and canthopexy methods applied.

Keywords: Schwannoma, facial nerve, surgical treatment.

Introduction: Facial nerve schwannoma is a rare benign tumor which can be seen on facial nerve. It is difficult to separete from

vestibuler schwannoma with magnetic resonance imaging (MRI). General somatic sensorial branch, and taste branches of the

facial nerve is located on geniculate ganglion. Although facial nerve involvement by schwannoma is a rare entity, it might be

presented by newly onset facial nerve paresis or paralyses, conductive type hearing loss due to otitis media or mass effect (1).

We are presenting a facial nerve schwannoma of the tympanic segment which obstruct mastoid segment and cause facial nerve

paralyses, treated via transmastoid surgical excision successfully.

Case Report: Forty six years old male patient is admitted to outpatient clinic with complaint of ongoing ear drainage 7 months

ago. Patient was prescribed with local antibiotherapy but otitis media was not healed so he was operated. During surgery it

was recognised that there was a mass on the middle ear cavity so surgeon took biopsy and decided to finalize the surgery.

The pathologic investigation was facial nerve schwannoma so the patient was refered to our clinic. On physical examination the

patient has house brackman (HB) stage 3 facial paralyses. After MRI and CT scan investigation the patient is decided to operate

with transmastoid approach (Figure 1,2). During surgery we have recognised that facial nerve of tympanic segment is defective.

The tumor arised from this segment and spreaded to mastoid segment. Malleus and incus bones were eroded duo to tumor and

tegment tympany also eroded but dura was intact. All the tumor was resected successfullly. The pathologic investigation also

showed the schwannoma (Figure 3) After surgery facial nerve paralyses remained stabil so plastic surgery clinic applied upper

eyelid implant and canthopexy.

Discussion: Facial nerve tumors might be seen any part of the facial nerve but commonly seen on perigeniculate and tympanic

segment. In our case the tumor was detected on the tympanic segment. Most typical symptoms are facial nerve paresis or

paralyses, hearing loss, tinnitus, otorhea, otalgia and vestibular symptoms (2).In our case both facial paralysis and otorhea

were detected. Facial nerve schwannoma is the most common tumor of the facial nerve. Saito et al. showed in a study that

intratemporal schwannoma has a incidence of 0.8 % in a 600 temporal bone material (3). In our case we have diagnosed the

tumor on the tympanic segment. Facial nerve schwannoma can be treated by microsurgery methods. Facial nerve functions

should be supplied by these methods. Treatment methods are wait and observe, fallopian canal decompression and steotaxic

surgery (4). In our case we decided to perform surgery due to facial nerve paralysis and otorhea. If there is not any facial

weakness, the method which preserve the facial function, should be used in first response. On the other hand , when the facial

nerve paralysis, labyrinthine segment erosion or brainstem compression are detected the facial nerve might not be preserved

during surgery (5). In our case we performed the transmastoid approach to excise the facial nerve schwannoma. At the end of the

surgery the facial nerve function is not changed. In order to supply the eye clousure, plastic surgeon performed the canthopexy

and upper eyelid implant. On the follow up we do not detect any recurrence. We should keep in mind the facial nerve schwannma

in middle ear cholesteatoma cases.

References

1. Kirazlı T, Oner K, Bilgen C, Ovul I, Midilli R. Facial nerve neuroma: Clinical,Diagnostic and surgical features. Skull base. 2014;14:115-120.

2. O’Donoghue GM, Brackmann DE, House JW, Jackler RK. Neuromas of the facial nerve. Am J Otol. 1989;10:49–54

3. Saito H, Baxter A. Undiagnosed intratemporal facial nerve neurilemomas. Arch Otolaryngol. 1972;95:415–419.

4. Minovi A, Vosschulte R, Hofmann E, Draf W, Bockmuhl U. Facial nerve neuroma: surgical concept and functional results. Skull

Base. 14:195–200. discussion 200–191, 2004.

5. Shirazi