Aim: Non-progressive ataxias with cerebellar hypoplasia are a rarely seen heterogeneous group of hereditary cerebellar ataxias.
Method: Three sib pairs from three different families with this entity have been reviewed, and differential diagnosis has been
discussed. Results: In two of the families, the parents were consanguineous. Walking was delayed in all the children. Truncal
and extremity ataxia were then noticed. Ataxia was severe in one child, moderate in two children, and mild in the remaining
three. Neurological examination revealed horizontal, horizonto-rotatory and/or vertical nystagmus, variable degrees of mental
retardation, and pyramidal signs besides truncal and extremity ataxia. In all the cases, cerebellar hemisphere and vermis
hypoplasia were detected in MRI. During the follow-up period, a gradual clinical improvement was achieved in all the
Conclusion: Inheritance should be considered as autosomal recessive in some of the non-progressive ataxic syndromes.
Congenital non-progressive ataxias are still being investigated due to the rarity of large pedigrees for genetic studies. If further
information on the aetiopathogenesis and clinical progression of childhood ataxias associated with cerebellar hypoplasia is
to be acquired, a combined evaluation of metabolic screening, long-term follow-up and radiological analyses is essential.
Key Words: Cerebellar hypoplasia, congenital non-progressive ataxic syndromes