A very rare and progressive cerebellar dyssynergia
with intention tremor first localized to one extremity, convulsions, and
myoclonic epileptic jerks. Ragged red fibers are seen on muscle biopsies.
Dentate Cerebellar Ataxia; Dentatorubral Atrophy; Primary
First described by James Ramsay Hunt, an American
neurologist in 1921.
Autosomal dominant with reduced penetrance.
Neurological lesions or anomalies are often
observed (cerebellar dentate nucleus, degeneration of globus pallidus,
elevated cerebrospinal fluid [CSF] uric acid); muscle biopsy shows presence of ragged red
fibers that probably are caused by mitochondrial abnormalities, which could explain
the pathophysiology of this syndrome. Controversy exists about considering
Ramsay Hunt syndrome as a specific entity.
Association of myoclonus ataxia and occasional seizures.
Neurological signs are isolated. No other
association is known. Myoclonus, cerebellar ataxia, intention tremor, and
occasional tonic-clonic seizures are the only symptoms.
Evaluate the neurological
repercussion (clinical, EEG, CT) and muscular status.
Patients should be considered epileptic and the
use of anesthetic agents inducing seizures (e.g., enflurane, sevoflurane) should be
The antiepileptic medication(s) should be continued
until the morning of surgery. Because of the presence of muscular
abnormalities and risk (undocumented) of hyperkalemic response it is recommended to avoid
succinylcholine. Consider interaction between antiepileptic treatment and anesthetic
Juvenile Paralysis Agitans of Hunt:
Autosomal dominant, this syndrome is characterized by mask-like facies,
parkinsonism, tremor, bradykinesia, dysarthria, rigidity, gait disturbance,
and flexion dystonia of fingers. Progression is slow. Onset in teens or
Dyssynergia Cerebellaris Myoclonica of Hunt
(Cerebelloparenchymal Disorder V, Spinodentate Atrophy): Autosomal
recessive with ataxia, myoclonic jerks, dentate neuron loss superior, and
cerebellar peduncle fiber loss.
Hunt JR: Dyssynergia cerebellaris myoclonica—Primary atrophy of the
dentate system: A contribution to the pathology and symptomatology of the
cerebellum. Brain 44:490, 1921.
Marsden CD, Obeso JA: Viewpoints on the Ramsay Hunt syndrome: 1. The Ramsay
Hunt syndrome is a useful clinical entity. Move Disord