What is Ramsay Hunt Syndrome?
Ramsay Hunt syndrome (RHS) is a neurological disorder caused by reactivation of the varicella-zoster virus (VZV) in the geniculate ganglion of the facial nerve, characterized by the triad of ipsilateral facial paralysis, painful vesicular lesions on the ear or in the mouth, and ear pain. 1, 2, 3
Clinical Presentation
The classic diagnostic triad includes:
- Ipsilateral lower motor neuron facial paralysis affecting all facial muscles on one side 1, 2, 4
- Vesicular rash (fluid-filled blisters) on the external ear canal, pinna, posterior auricular surface, or oral mucosa 1, 2, 3
- Severe otalgia (deep, tearing ear pain) that often precedes other symptoms 1, 2, 5
Additional Common Features
- Vestibulocochlear nerve involvement causing hearing loss, tinnitus, vertigo, nausea, vomiting, and nystagmus occurs frequently due to anatomic proximity of the geniculate ganglion to the eighth cranial nerve 2, 4, 5
- Sensorineural hearing loss can be documented on audiometric testing 1, 5
- The vesicular lesions are pathognomonic when present, though they may appear after facial weakness develops 1, 2
Key Diagnostic Distinctions
RHS must be differentiated from other causes of facial palsy:
- Bell's palsy is a diagnosis of exclusion requiring absence of ear pain and external ear findings; the presence of ear pain, periauricular swelling, and vesicular lesions rules out idiopathic Bell's palsy 1
- Acute otitis media with facial palsy shows moderate-to-severe tympanic membrane bulging, middle ear effusion, and reduced membrane mobility on pneumatic otoscopy, whereas RHS typically shows an intact but erythematous tympanic membrane with normal mobility 1
- Simple acute otitis externa never produces facial nerve paralysis; its presence should prompt consideration of RHS or necrotizing otitis externa in high-risk patients 1
Pathophysiology
The syndrome occurs when latent VZV reactivates in the geniculate ganglion and produces inflammatory reaction in the seventh cranial nerve 4, 6. The virus can spread via:
- Direct perineural and transaxonal spread between contiguous cranial nerves 7
- Hematogenous dissemination between nerves with shared blood supply 7
- Retrograde transaxonal spread from the ganglion into the brain parenchyma, rarely causing encephalitis 6
Epidemiology and Risk Factors
- RHS accounts for 2-10% of all facial nerve palsy cases 4
- Older adults and immunocompromised patients are at increased risk for VZV reactivation and more severe manifestations including encephalitis 2, 8
- The condition is less common than Bell's palsy but carries worse prognosis, particularly when diagnosis and treatment are delayed 3, 4
Prognosis
Early diagnosis and treatment within 72 hours are crucial for optimal facial nerve recovery and prevention of long-term complications including persistent facial weakness, hearing impairment, and chronic pain 1, 2, 3, 5. Multiple cranial neuropathies, though rare, are associated with poorer prognosis and significant morbidity affecting speech, swallowing, hearing, and eye protection 7.