cerebral edema [L, cerebrum + Gk, oidema, swelling] , an accumulation of fluid in the brain tissues. Causes include infection, tumor, trauma, or exposure to certain toxins. Because the skull cannot expand to accommodate the fluid pressure, brain tissues are compressed. Early symptoms are changes in level of consciousness: sluggishness, then dilation of one or both pupils, and a gradual loss of consciousness. Cerebral edema can be fatal.
