A previously healthy man was admitted due to a severe rise in the arterial blood pressure. The patient was found confused and drowsy, but the neurological investigation was otherwise normal. A computerized tomographic scan of cerebrum showed widespread areas of diminished density in the brain. After normalization of the arterial blood pressure, a new computerized tomographic scan did not show any pathological enhancement. The total regression of signs and symptoms after the normalization of the blood pressure support the assumption that a severe increase in blood pressure leads to formation of focal cerebral oedema.