Transcranial Doppler ultrasound recording with compression test in patients with tumors involving the carotid arteries.

Transcranial Doppler ultrasound (TDU) recording is presented as a diagnostic method for the evaluation of the cerebral cross-flow in patients in whom, for therapeutic reasons, ligature or resection of the common or internal carotid artery is planned. Examinations were performed under normal conditions and while using manual compression of the ipsilateral carotid artery. Patients with various skull base and neck tumors were examined and in all patients an immediate decrease of the flow velocity in the middle cerebral artery (MCA) of 25 to 90% was registered. In 39% of these patients the flow velocity of the MCA reached 90% or more of its value under normal conditions within a short interval. In 29% of the patients the flow velocity of this vessel under manual compression of the carotid artery remained under 50% of its original value. In 68% of the cases TDU recording with manual compression of the carotid artery showed reliable results for the function of cerebral collateralization as a prognostic factor of ischemic risk due to hemodynamic changes after carotid ligature. In these cases no further examination of the cerebral cross-flow conditions was carried out. This method is convenient, harmless to the patient, inexpensive, does not require sophisticated equipment, and yields reproducible results when compared with cerebral angiography.