[Changes in the intracranial volume-pressure relations and visual evoked potentials produced by stabilized and compensated additional volume].

The experiment was carried out on 17 cats with intracranial volume-pressure relations changed by means of an epidural balloon of 1.0 ml volume (group I--12 cats) and 0.5 ml (group II--5 cats). The duration of compression exerted by the balloon was 360 min. The intracranial pressure, volume-pressure responses, resistance to cerebrospinal pressure resorption and visual evoked potentials were determined at intervals of 60 minutes. In group I pressure exerted by 1 ml balloon was followed by changes of volume-pressure relations and visual evoked potentials which increased with duration of the experiment. In group II the changes were noted only in the volume-pressure responses and resistance to CSF resorption at the time of balloon volume rise from 0 to 0.5 ml. Maintenance of this balloon volume in the cranial cavity caused no further changes of volume-pressure parameters or visual evoked potentials during 360 minutes of the experiment.