[Atraumatic measurement of intracranial pressure].

This paper presents a new method for measuring intracranial pressure (ICP), which is completely non-invasive by using an isolated "headband electrode". The head itself - as a dielectric--forms a capacitor. A high frequency alternating voltage field is applied to this system (1-1.5 MHz) whereby a measuring signal is obtained which depends on the dielectric properties of the head. These, in turn, primarily depend on the filling status of the intracranial space. In addition, a pulse wave can be plotted as a result of cardiac and respiratory cycles. This combined information permits the calculation of actual ICP values with the help of a simple Basic PC programme. The measuring system was tested in 20 patients with intracranial space-occupying lesions. Their ICP values were known from invasive measurement and the obtained correlation was R = 0.983.