A spinocerebellar degeneration. Abnormal eye movements
include absent rapid saccades (scanning) and abnormally slow pursuit
(tracking). Lethal within 10 years of onset.
Cerebellar Degeneration with Slow Eye Movements.
Rare disease with autosomal
dominant inheritance (also possibly an autosomal recessive form).
Slowing of all eye movements thought to be caused
by a brainstem lesion of the paramedian pontine reticular formation. Clinical features include an
abnormal accompanying movements of head and neck; spinocerebellar
degeneration with abnormal gait (ataxia); progressive intellectual impairment,
extrapyramidal dysfunction and peripheral neuropathy. Skeletal abnormalities
can occur. Muscle biopsy shows nonspecific mitochondrial abnormalities.
Magnetic resonance imaging studies of the brain show a significant degree of
cerebellar and brainstem atrophy. Death occurs within 10 years of onset.
It is recommended to evaluate carefully the neurological function
(clinical, EEG, CT/MRI) and muscular condition for the presence of myotonia. Careful intraoperative positioning
Najim al-Dim AS, al-kurdi A, Dasouki M, et al: Autosomal recessive ataxia, slow eye movements
and psychomotor retardation. J Neurol Sci 12(4):61, 1994.
Wadia NH, Swami RK: A new form of heredo-familial spinocerebellar
degeneration with slow eye movements. Brain