Facial Schwannoma: Difference between revisions
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==== Other symptoms ==== | ==== Other symptoms ==== | ||
These can include pain, balance difficulties, vertigo and tinnitus. | These can include pain, balance difficulties, vertigo and tinnitus. | ||
==== Incidence of Symptoms ==== | |||
A 2006 study examined 24 patients with Facial Schwannoma and reported the following incidence of symptoms: | |||
Peripheral facial nerve neuropathy in 10 cases, ie. 42% of patients. This incompassed weakness, focal twitch, and/or full hemifacial spasm. | |||
Sensorineural hearing loss occurred in 7 cases (29%), | |||
Conductive hearing loss in 4 cases (17%) | |||
Clinical presentation with a middle ear mass in 3 cases (13%) | |||
Vestibular symptoms in 3 cases (13%) | |||
== Diagnostic Procedures == | == Diagnostic Procedures == | ||
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Yonsei Med J. 1998 Apr;39(2):148-53. | Yonsei Med J. 1998 Apr;39(2):148-53. | ||
</ref><ref>R.H. Wiggins, H.R. Harnsberger, K.L. Salzman, C. Shelton, T.R. Kertesz and C.M. Glastonbury | </ref><ref>R.H. Wiggins, H.R. Harnsberger, K.L. Salzman, C. Shelton, T.R. Kertesz and C.M. Glastonbury | ||
The Many Faces of Facial Nerve Schwannoma | The Many Faces of Facial Nerve Schwannoma | ||
American Journal of Neuroradiology March 2006, 27 (3) 694-699; | American Journal of Neuroradiology March 2006, 27 (3) 694-699; | ||
</ref>; however, this often misses a Facial Schwannoma because of the very small diameter of the facial nerve - approx 1 mm - and the thickness of the image slices - 5 mm. | </ref>; however, this often misses a Facial Schwannoma because of the very small diameter of the facial nerve - approx 1 mm - and the thickness of the image slices - 5 mm. | ||
Revision as of 21:02, 29 November 2019
This article or area is currently under construction and may only be partially complete. Please come back soon to see the finished work! (29/11/2019)
Original Editor - Wendy Walker
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Introduction[edit | edit source]
Facial Schwannoma is a very rare tumour which grows on the 7th Cranial Nerve, the Facial Nerve.
It is also known as a Facial Neuroma.
Clinically Relevant Anatomy[edit | edit source]
For details of the path of the Cranial Nerve 7, please see the Facial Nerve page.
Location of Tumour[edit | edit source]
The majority of tumours are found on the segment of the nerve within the internal auditory canal, with one UK study[1] of a cohort of 28 Facial Schwannoma patients reporting 68% incidence in this section of the nerve.
The same study also found multi-segmental lesions in 46% of the patients.
Facial weakness was most commonly associated with involvement of the labyrinthine segment (89%).
Mechanism of Injury / Pathological Process[edit | edit source]
Schwannomas are extremely slow growing tumours, the majority of which are benign[2].
They originate from the Schwann cell sheath of the facial nerve.
Clinical Presentation[edit | edit source]
The presentation frequently comprises hearing loss and facial weakness or paralysis[3]:
Facial Palsy/Paralysis[edit | edit source]
In Facial Schwannoma, the patient often reports a very slow onset unilateral facial palsy, ie. paralysis or weakness of the facial muscles. It is a lower motor neuron palsy.
There are more details on the Facial Palsy page.
Hearing Loss[edit | edit source]
The Auditory or Acoustic Nerve, 8th Cranial Nerve, travels next to the facial nerve in the Internal Auditory Canal. A growing tumour on the portion of the Facial Nerve within the Internal Auditory Canal can therefore cause compression on the Acoustic Nerve, which results in hearing loss.
Other symptoms[edit | edit source]
These can include pain, balance difficulties, vertigo and tinnitus.
Incidence of Symptoms[edit | edit source]
A 2006 study examined 24 patients with Facial Schwannoma and reported the following incidence of symptoms:
Peripheral facial nerve neuropathy in 10 cases, ie. 42% of patients. This incompassed weakness, focal twitch, and/or full hemifacial spasm.
Sensorineural hearing loss occurred in 7 cases (29%),
Conductive hearing loss in 4 cases (17%)
Clinical presentation with a middle ear mass in 3 cases (13%)
Vestibular symptoms in 3 cases (13%)
Diagnostic Procedures[edit | edit source]
In the majority of centres, a brain MRI is used as part of the evaluation of facial paralysis[4][5]; however, this often misses a Facial Schwannoma because of the very small diameter of the facial nerve - approx 1 mm - and the thickness of the image slices - 5 mm.
The optimal imaging technique is an MRI of the internal auditory canals, with and without the contrast agent gadolinium. This imaging technique allows thinner slices through the temporal bone, it is much more likely to show the tumour[6].
Outcome Measures[edit | edit source]
- Sunnybrook Facial Grading System
- House-Brackmann facial nerve grading scale
- Linear Measurement Index
- Facial Disability Index
Management / Interventions[edit | edit source]
Facial Schwannomas are frequently resected surgically, although if the tumour is not causing any problems it will generally just be monitored and no surgical intervention undertaken.
Patients at high risk of a corneal ulcer may be offered oculoplastic surgery to protect the eye.
For patients with dense facial palsy and no nerve function, a number of surgical interventions may be used. These fall into the following categories:
- Facial reanimation surgeries which involve nerve graft or anastomosis
- Facial reanimation surgeries which involve muscle transposition
- Static surgeries, ie. plastic surgery to improve symmetry at rest but no improvement in movement
Differential Diagnosis[edit | edit source]
Parotid Adenoma[2]
Physiotherapy Management[edit | edit source]
Resources[edit | edit source]
add appropriate resources here
References[edit | edit source]
- ↑ Doshi J, Heyes R, Freeman SR, Potter G, Ward C, Rutherford S, King A, Ramsden R, Lloyd SK. Clinical and Radiological Guidance in Managing Facial Nerve Schwannomas Otology & Neurotology. 36(5):892–895, JUNE 2015
- ↑ 2.0 2.1 Jayashankar N, Sankhla S. Facial schwannomas: Diagnosis and surgical perspectives. Neurol India [serial online] 2018 [cited 2019 Nov 28];66:144-6. Available from: http://www.neurologyindia.com/text.asp?2018/66/1/144/222821
- ↑ Lahlou G; Nguyen Y; Russo FY; Ferrary E; Sterkers O; Bernardeschi D Intratemporal facial nerve schwannoma: clinical presentation and management. Eur Arch Otorhinolaryngol. 2016; 273(11):3497-3504 (ISSN: 1434-4726)
- ↑ Chung SY, Kim DI, Lee BH, Yoon PH, Jeon P, Chung TS. Facial nerve schwannomas: CT and MR findings. Yonsei Med J. 1998 Apr;39(2):148-53.
- ↑ R.H. Wiggins, H.R. Harnsberger, K.L. Salzman, C. Shelton, T.R. Kertesz and C.M. Glastonbury The Many Faces of Facial Nerve Schwannoma American Journal of Neuroradiology March 2006, 27 (3) 694-699;
- ↑ Djalilian, Hamid R. MD Symptoms: Hearing Loss and Facial Paralysis The Hearing Journal: May 2014 - Volume 67 - Issue 5 - p 11,14
