spinocerebellar ataxia prognosisataxia telangiectasia prognosishereditary ataxia prognosisfriedreich's ataxia prognosismedication for cerebellar ataxiaacute cerebellar ataxia treatmentinherited cerebellar ataxiaparaneoplastic cerebellar ataxiacerebellar ataxia curecerebral ataxia prognosisidiopathic cerebellar degenerationcerebellar degeneration syndrome