What is
Ramsay Hunt syndrome??
Ramsay Hunt syndrome is a disease affecting the external auditory
canal associated with the following symptom complexes:
1. Lower motor neuron type of facial nerve palsy
2. Herpetic blisters of the skin of the external
auditory canal
3. Otalgia
This syndrome was first described by J. Ramsay Hunt in
1907. He described patients with Otalgia
associated with cutaneous and mucosal rashes.
He attributed it to the infection of geniculate ganglion by Herpes virus
type 3.
Why it occurs??
The primary pathophysiology is located in the
geniculate ganglion of the facial nerve.
Geniculate ganglion is found to be affected by Human Herpes virus type 3
i.e. (Varicella zoster virus). Varicella
zoster virus have been identified from tears of these patients by polymerase
chain reaction. Infact Varicella zoster
virus have also been identified from tears of patients with Bell's palsy.
These patients have deep seated pain in the affected
ear associated with vertigo, tinnitus, ipsilateral transient hearing loss and
lower motor neuron type of facial palsy.
These symptoms develop due to involvement of the geniculate ganglion of
the facial nerve located near the petrous pyramid portion of the temporal
bone. The site of rash varies from
patient to patient due to individual
variations in the areas supplied by the nervous intermedius of wrisburg
(sensory branch of facial nerve). Rashes
may be present in the anterior 2/3 of the tongue, soft palate, external
auditory canal and the pinna.
Morbidity/Mortality
This disease is usually not associated with
mortality. It is a self limiting
disease, with morbidity due to facial nerve palsy. Complete recovery of the nerve is seen only
in 50% of patients as compared to more than 90% in Bell's palsy.
What are the symptoms??
Patient has deep seated pain in the affected ear. The pain is intermittent in nature, radiating
towards the pinna of the ear. There is
associated diffuse dull aching background pain. Patients also give history of
exposure to Varicella virus infections (chicken pox). The classic Ramsay Hunt syndrome is
associated with 1. Pain in the ear, 2.
Vertigo and ipsilateral hearing loss, 3. Tinnitus, and 4. Facial palsy (LMN
type). Rash or blisters can also be seen
along the distribution of nervus intermedius.
These herpetic blisters in the external auditory canal may become
secondarily infected causing cellulitis.
What investigations are done??
Basic investigations like blood count, ESR and
electrolytes estimation must always be done in these patients.
Virology:
1. Varicella virus the causative agent responsible for
this syndrome also causes chicken pox in children
2. Serologic tests for Varicella virus is positive
3. Varicella virus can be isolated and cultured form
the fluid extruding from the blisters
4. It can also be detected by PCR on samples of tear
fluid from these patients.
5. Audiometry demonstrates sensorineural hearing loss
6. Unilateral caloric weakness may be present on
electronystagmography (ENG).
Histology:
The affected ganglia are found to be swollen and
inflammed. The inflammatory reaction is
lymphocytic in nature. Some of the cells
in the ganglia may show evidence of degeneration.
CSF analysis is not indicated in these patients.
How it is treated ??
1. Steps towards alleviating pain: Carbamazepine can be prescribed in doses of
400 mg / day in divided doses. Temporary
relief of Otalgia in geniculate neuralgia may be achieved by applying a local
anesthetic or cocaine to the trigger point, if in the external auditory canal.
2. Corticosteroids and oral acyclovir can be
administered. Steroids in the form of
prednisolone can be administered orally in doses of 10mg twice a day. Steroids should not be stopped abruptly. The dosage needs to be tapered. Acyclovir can be administered in doses of 800
mg orally 5 times a day.
3. Management of vertigo: can be managed using
meclizine in doses of 25 mg orally 4
times a day.
4. Care must be taken to prevent exposure keratitis
because of the inability to close the eye lids.
The patients must wear protective goggles
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