Indication for invasive diagnostic studies and surgical therapy in cerebral ischemia, based on results of non-invasive transcranial Doppler sonography.

In order to better define patients who might benefit from cerebral revascularization surgery, transcranial Doppler sonography was used in more than 480 patients. Thus invasive diagnostic studies could be limited to probable surgical candidates. Transcranial Doppler sonography has proven to be reliable for the study of the degree of efficacy of intracranial collateral pathways in hemodynamic borderline situations. Over the last 4 years, the application of the algorithm presented in this paper resulted in a reduction of the number of candidates for surgical revascularization to 19.