Peripheral facial nerve (LMN) palsy accompanied by an erythematous vesicular rash on the ear (zoster oticus) or in the mouth.
2nd M/C cause of atraumatic peripheral facial paralysis
History
J Ramsay Hunt, who described various clinical presentations of facial paralysis and rash, also recognised other frequent symptoms and signs such as tinnitus, hearing loss, nausea, vomiting, vertigo, and nystagmus. He explained these eighth nerve features by the close proximity of the geniculate ganglion to the vestibulocochlear nerve within the bony facial canal. Hunt’s analysis of clinical variations of the syndrome now bearing his name led to his recognition of the general somatic sensory function of the facial nerve and his defining of the geniculate zone of the ear. It is now known that varicella zoster virus (VZV) causes Ramsay Hunt syndrome.
The syndrome was first described by James Ramsay Hunt (1872–1937), a prominent American neurologist of the time
Classification
Ramsay Hunt syndrome (RHS) type 1
Rare, degenerative, neurological disorder characterized by myoclonus epilepsy, intention tremor, progressive ataxia and occasionally cognitive impairment.
Ramsay Hunt syndrome (RHS) type 2
Disorder that is caused by the reactivation of varicella zoster virus in the geniculate ganglion, a nerve cell bundle of the facial nerve.
Pathophysiology
Functional anatomy of the facial nerve. Proximally, the four cranial nerve nuclei involved in facial nerve functions are shown at the pontomedullary junction: the motor nucleus of VII, the nucleus of the solitary tract, the superior salivatory nucleus, and the spinal nucleus of V. Special visceral efferent motor fibres from the motor nucleus of VII (solid red line) exit the brain stem and travel through the internal acoustic meatus to enter the bony facial canal and exit through the stylomastoid foramen to supply facial muscles. In Ramsay Hunt syndrome, these fibres are affected as they pass through the geniculate ganglion, disrupting motor functions of the seventh cranial nerve. The solitary tract receives special visceral afferent taste fibres (solid blue line) emanating from the anterior two thirds of the tongue. These fibres travel with the chorda tympani through the petrotympanic fissure (not shown). The cell bodies of these special visceral afferent fibres are in the geniculate ganglion which is the site of VZV reactivation when vesicles erupt on the tongue. The fibres reach the brain stem via the nervus intermedius and can be affected by local inflammation as they pass the geniculate ganglion. Special visceral efferent parasympathetic fibres (thin dotted red line) to the lacrimal and salivary glands emanate from the superior salvitory nucleus, travel in the nervus intermedius, and branch at the geniculate ganglion into the greater petrosal and chorda tympani nerves. Decreased lacrimation may result from involvement of these fibres as they branch at the level of the geniculate ganglion. Special visceral efferent sympathetic fibres (thick dotted red line) emanate from the carotid plexus on the internal carotid artery and join the greater petrosal nerve as these structures pass through the foramen lacerum (not shown). The sympathetic fibres parallel the parasympathetic fibres as they supply the same areas. The spinal nucleus of V receives general somatic afferent fibres from the geniculate zone of the ear via the chorda tympani. Cell bodies of these neurons are located in the geniculate ganglia and are the site of VZV reactivation in classic Ramsay Hunt syndrome causing vesicular eruptions in geniculate zones. | Sweeney, C. J., & Gilden, D. H. (2001). Ramsay Hunt syndrome. Journal of Neurology, Neurosurgery &Amp; Psychiatry, 71(2), 149 LP-154. https://doi.org/10.1136/jnnp.71.2.149
Can project into neighboring regions of the face and nape of the neck
Herpetic eruptions in any cranial dermatome
Cutaneous findings of herpes zoster oticus pointing to the diagnosis RHS typically manifest in Hunt’s zone (eardrum, the external auditory canal and the central portion of the ear, the cavum conchae)
Clinical features of Ramsay Hunt syndrome. Note peripheral facial weakness characterised by a widened palpebral fissure and decreased forehead wrinkling and smile on the right, often associated with vesicles in the ipsilateral ear, on the hard palate, or on the anterior two thirds of the tongue. | Sweeney, C. J., & Gilden, D. H. (2001). Ramsay Hunt syndrome. Journal of Neurology, Neurosurgery &Amp; Psychiatry, 71(2), 149 LP-154. https://doi.org/10.1136/jnnp.71.2.149
Case studies:
Patient 1 (56y/F): The patient reported pain of increasing intensity in the left ear for one week. Two days before hospital admission weeping lesions developed on the concha of the left ear. Simultaneously the patient observed facial paralysis and a partial loss of hearing on the left side as well as vertigo with nausea and vomiting.
Patient 2 (81y/F): Three days before hospital admission the patient first noticed pruritus on the right ear. Tw o days later distinct pain developed here with projection to the right side of the face. In the further course loss of control over the right eyelid, the right corner of the mouth and the right half of the tongue. During the hospital stay the patient complained of sensitivity to noise in the right ear.
Patient 3 (76y/F): The patient developed acute severe pain on the right side of the face and occipital region, subsequently accompanied by hearing loss and cervical skin lesions on the right side. Hospital admission four days after the onset of symptoms.
Differential diagnosis:
Bell’s palsy (facial paralysis without rash)
Patients with Ramsay Hunt syndrome often have more severe paralysis at onset and are less likely to recover completely
