Olivopontocerebellar Atrophy

[Sandy-Clarke]

  : : Hello:
  : : Can you tell me what diagnostic test currently are used to diagnose and confirm OPCA???
  : : Thank you very much!!
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  : Dear Dave:
  : Cerebellar degenerations (also called spinocerebellar degenerations) can either be sporadic or heredofamilial. Heredofamilial cerebellar degenerations can be either autosomal dominant (various types termed spinocerebellar ataxia = SCA 1 - 7, DRPLA, Machado-Joseph disease, etc) or autosomal recessive (Friedreich's ataxia, and some other rare types).
  : The syndrome of progressive ataxia (imbalance of gait, incoordination of hands, slurred speech), in association with some other characteristic abnormalities (peripheral neuropathy, optic atrophy, retinitis pigmentosa, dementia, corticospinal dysfunction, oculomotor dysfunction, etc) is seen with heredofamilial forms. Ataxia is associated with autonomic dysfunction and/or parkinsonian features in sporadic cases. Either sporadic or autosomal dominant forms of cerebellar degeneration can be associated with atrophy of the cerebellum, pons and inferior olives, either on MRI, or at autopsy. Hence, OPCA (olivopontocerebellar atrophy) is used as a descriptive term for these disorders.
  : The diagnosis of sporadic cerebellar degeneration or OPCA remains clinical. Isolated cases of heredofamilial cerebellar degeneration, and some specific secondary causes of cerebellar degeneration (such as with malignancies or toxins) need to be excluded.
  : Specific genes of several of the forms of heredofamilial spinocerebellar ataxia have been identified. Tests for SCA 1, 3, 3 (MJD), 6, 7, DRPLA, and Friedreich's ataxia are now commercially available. Other ataxias can also be tested for with linkage analysis if large families are available.