[Quantitative determination of regional cerebral circulation with Xe-133: lst experiences using this method in the clinic].

After injection of the radioactive noble gas Xe133 into the A. carotis interna, the regional blood flow in the brain is determined with a 10-channel measuring unit. From the first clinical evaluation of the findings in 35 patients, the following conclusions can be drawn: 1. In epileptics, a localised hyperaemia very probary indicates a latent increased convulsive activity. 2. The measurement of the cerebral blood flow does not yield a contribution to the diagnosis of the type of cerebral tumours. 3. As a consequence of mass shifting of space occupying processes particularly endangered brain sections, also remote from the focus proper, show a localised pathological hyperaemia (morbid "luxus perfusion"). 4. Of greatest importance is the method for clearing up of pathophysiological relations, the clearing up of questions in connection with the blood/brain barrier function, and for the indications for and estimation of the results of vascular-surgical interventions.