понедельник, 1 декабря 2008 г.

Signs of brain tumours can be both general and localized.

Signs of brain tumours can be both general and localized.
General symptoms of are results of processes that occur in the skull as a whole, while local or focal symptoms are caused by pressure of the growing tumour on certain tissues of the brain.
Common symptoms of brain tumours include headaches and seizures. About a third of patients develop some form of epilepsy, and in about 50% cases, seizures appears as early symptom, even before headaches. Sudden onset of epilepsy is considered to be one of earliest warnings signs of a brain tumour.
Tumour-caused headaches usually develop during late stages. They are caused by cerebral edema (accumulation of liquid in the brain), or by increased intracranial pressure. Sometimes headaches are accompanied by nausea or vomiting, which causes an erroneous diagnosis of cerebral concussion. A characteristic symptom of brain tumour is increased pain when patient is lying down, in the mornings or during physical exertion.
Local or focal symptoms depend on which part of the brain is constricted by the tumour. For example, tumour in the occipital lobe of the brain causes vision disorders, tumour in the parietal lobe causes disorders connected of sensory and motor function, tumour in frontal lobe is characterized by diminished ability for self-criticism and tumour in the middle lobe causes headaches, weakness and nausea.