A bump on your head could lead to a permanent disability or cognitive deficits if not attended in time, says a case study. According to the case study, when Irene Gatti de Leon slipped on the ice and bumped her head, she wasn`t too concerned. Two months later, she began to experience weakness in her right leg and right arm while she and her husband were visiting their daughter in suburban Chicago. She made an urgent appointment with Loyola University Medical Centre neurology professor Jose Biller, a fellow native from Uruguay whom she has known for years. Biller ordered an immediate MRI scan, which showed a large subdural hematoma -- a mass of blood on the surface of the brain. With the hematoma compressing the brain, de Leon was in imminent danger of suffering permanent paralysis or cognitive deficits, similar to disabilities caused by strokes, said a university statement Biller referred de Leon to Loyola neurosurgeon Douglas Anderson, who stayed late to perform emergency surgery. Anderson drilled two holes in her skull and drained the hematoma, which was about two inches long and 1.5 inches thick. De Leon has made a full recovery. Subdural hematomas are triggered by head injuries that cause blood vessels between the surface of the brain and its outer covering (the dura) to stretch and tear. They usually are caused by severe head injuries that cause bleeding, which rapidly fills the brain area. But less severe head injuries can cause chronic subdural hematomas. These slow bleeds may not cause symptoms for days or weeks. De Leon`s case "is an excellent illustration of why patients should not ignore neurological symptoms," Biller said.