Tumour: pineal germinoma or teratoma, pineocytoma glioma, metastasis

Hydrocephalus

Vascular: midbrain or thalamic haemorrhage or infarction

Metabolic: e.g. Niemann–Pick variants, Gaucher’s disease

Degeneration: progressive supranuclear palsy, Huntington’s disease, cortical basal degeneration

Drug-induced: barbituates, carbamazepine, neuroleptics

Miscellaneous: Multiple Sclerosis, Whipple’s disease, hypoxia, syphilis