Sanjana Ashok

Introduction

Ramsay Hunt syndrome (RHS), also known as herpes zoster oticus, is caused by reactivation of latent varicella–zoster virus (VZV) within the geniculate ganglion of the facial nerve (1). It represents an important and distinct cause of acute lower motor neurone facial nerve palsy and is associated with more severe disease and poorer recovery than idiopathic facial nerve palsy (Bell’s palsy) (1,2). From an ophthalmic perspective, RHS is clinically significant due to its association with lagophthalmos, corneal exposure, and sight-threatening ocular surface disease. Early recognition is critical, as management differs from Bell’s palsy and requires prompt antiviral therapy (2).

Epidemiology

Ramsay Hunt syndrome accounts for approximately 7% of all cases of acute facial nerve palsy (1). It occurs most commonly in older adults, with incidence increasing with age, reflecting declining VZV-specific cell-mediated immunity (6). Immunocompromised individuals, including those with HIV infection, malignancy, or long-term immunosuppressive therapy, are at increased risk (6). Compared with Bell’s palsy, RHS is less common but carries a significantly worse prognosis, with lower rates of complete facial nerve recovery (3).

Risk Factors

The principal risk factor for RHS is reactivation of latent VZV. Increasing age and immunosuppression are the strongest predisposing factors (1,6). Systemic illness, psychological stress, and recent infections may contribute to viral reactivation, although definitive triggers are often not identified (6). Unlike Bell’s palsy, which is a diagnosis of exclusion, RHS has a defined viral aetiology and should be actively considered in any patient presenting with facial nerve palsy and otological symptoms (1).

Clinical Presentation

Ramsay Hunt syndrome classically presents with the triad of ipsilateral lower motor neurone facial nerve palsy, severe otalgia, and a vesicular rash involving the external ear, auditory canal, or tympanic membrane (1). The rash may extend to the oropharynx, including the soft palate or tongue. In a minority of cases, vesicles may be absent or delayed, a presentation referred to as zoster sine herpete, which can make diagnosis more challenging (4).

Facial nerve palsy in RHS is often complete and more severe than in Bell’s palsy. Involvement of other cranial nerves is common, particularly the vestibulocochlear nerve, resulting in hearing loss, tinnitus, vertigo, and imbalance (1,3). Trigeminal nerve involvement may contribute to facial sensory disturbance and reduced corneal sensation.

Ocular manifestations are largely secondary to facial nerve dysfunction and include lagophthalmos, reduced blink reflex, epiphora, and exposure keratopathy. Reduced corneal sensation further increases the risk of corneal epithelial breakdown and secondary infection (4).

Investigations

Ramsay Hunt syndrome is primarily a clinical diagnosis. Polymerase chain reaction testing for VZV from vesicular fluid can confirm the diagnosis but is not routinely required (1). Audiological assessment should be considered in patients with hearing symptoms. Neuroimaging is reserved for atypical presentations or where alternative diagnoses such as stroke, neoplasia, or demyelinating disease are suspected (1).

From an ophthalmic perspective, slit-lamp examination is essential to assess corneal integrity, tear film adequacy, and signs of exposure keratopathy (4).

Management

The key management principle in Ramsay Hunt syndrome is early antiviral therapy and specialist ENT involvement, which distinguishes it from Bell’s palsy. Evidence and guidance consistently recommend treatment with oral antivirals, ideally initiated within 72 hours of symptom onset (2). Oral aciclovir, valaciclovir, or famciclovir are appropriate options, with valaciclovir often preferred due to improved bioavailability and simplified dosing (2,6).

Systemic corticosteroids are commonly prescribed alongside antivirals to reduce nerve inflammation. Combination therapy with aciclovir and prednisolone has been shown to improve facial nerve recovery, particularly when initiated early (2). This contrasts with Bell’s palsy, where corticosteroids alone are first-line and antivirals are not routinely recommended (5).

Early referral to ENT is recommended for confirmation of diagnosis, assessment of otological involvement, and multidisciplinary management (1,2). Ophthalmic management focuses on prevention of corneal exposure, with intensive preservative-free lubrication, night-time ointment, and eyelid taping where required (4). Patients with persistent exposure or corneal compromise should be referred urgently to ophthalmology, and surgical interventions such as temporary tarsorrhaphy or upper eyelid gold weight implantation may be required in refractory cases (4).

Prognosis in RHS is poorer than in Bell’s palsy, with lower rates of complete facial nerve recovery, particularly in older patients and those with complete paralysis at presentation (3). Early antiviral treatment is associated with improved outcomes and reduced long-term morbidity (2).

Conclusion

Ramsay Hunt syndrome is an important cause of acute lower motor neurone facial nerve palsy with significant ophthalmic implications. The presence of otalgia, vesicular ear rash, or vestibulocochlear symptoms should prompt consideration of RHS and immediate deviation from Bell’s palsy management pathways. Current evidence supports early ENT involvement and treatment with oral antivirals, alongside ocular surface protection to prevent sight-threatening complications. Recognition of this distinction is a key learning point for clinicians managing facial nerve palsy.

References

1. Sweeney CJ, Gilden DH. Ramsay Hunt syndrome. J Neurol Neurosurg Psychiatry. 2001;71(2):149–154.
2. Murakami S, Hato N, Horiuchi J, Honda N, Gyo K, Yanagihara N. Treatment of Ramsay Hunt syndrome with acyclovir-prednisone: significance of early diagnosis and treatment. Ann Neurol. 1997;41(3):353–357.
3. Yeo SW, Lee DH, Jun BC, et al. Analysis of prognostic factors in Ramsay Hunt syndrome. Otol Neurotol. 2007;28(8):1097–1101.
4. Lee HY, Kim MG, Park DC, Park MS, Byun JY, Yeo SG. Zoster sine herpete causing facial palsy. Am J Otolaryngol. 2012;33(5):565–571.
5. National Institute for Health and Care Excellence. Bell’s palsy: management. NICE Clinical Knowledge Summaries; 2023.
6. Gilden DH. Clinical practice. Herpes zoster. N Engl J Med. 2004;350(17):1786–1795