Pneumosinus dilatans frontalis refers to enlargement of the frontal sinus. This rare disorder may affect all paranasal sinuses, but frontal sinus involvement is most common.

Diffuse cerebellar atrophy has varied causes including alcoholic cerebellar degeneration, ataxia telangiectasia, olivopontocerebellar atrophy, Friedreich ataxia, prolonged exposure to phenytoin among other conditions.