Tumours of brain, meninges and spinal cord

The commonest brain tumour is metastatic cancer but it is rare for such tumours to present to neurosurgeons unless the primary malignancy is undiagnosed, or the metastasis is solitary and slow growing.

Primary CNS tumours are summarised in Table 22.1.

Table 22.1 Tumours of the central nervous system

Tumour	Origin	Features
Glioma	Derived from supporting tissues of the brain, types include: astrocytoma, oligodendrocytoma, ependymoma	Varying degrees of malignancy depending on cellularity, mitoses, pleomorphism and necrosis
Meningioma	Arise from meninges	Usually benign, rarely recur after removal
Neuroma	Acoustic neuroma (derived from eighth nerve) is commonest	Usually benign
Pituitary	Derived from pituitary gland	Clinical features: Visual disturbance due to pressure on the optic chiasma Metabolic abnormality if the tumour is endocrinologically active

Developmental Derived from abnormal islands of cells at points of neural tube closure, commonest examples are: craniopharyngioma, colloid cyst of third ventricle, medulloblastoma, choroid plexus papilloma Variable degree of malignancy

Cerebral haemorrhage

Cerebral haemorrhage is spontaneous bleeding within the cranial cavity. The three types are: