Meningioma is a type of tumour that forms on the membranes surrounding the brain, which are called the meninges. Meningiomas can squeeze the surrounding nerves, vessels and brain tissue, which can lead to the sufferer experiencing a variety of debilitating neurological symptoms. This type of tumour tends to grow slowly and can be present for some time before any symptoms appear. It's more commonly diagnosed in women than men, and it tends to be diagnosed more frequently in the elderly.