Identification and localization of intracerebral vessels by microvascular doppler in stereotactic pallidotomy and thalamotomy: technical note.

Abstract

To identify intracerebral vessels in proximity to the target for thermocoagulation in functional neurosurgery, we use a microvascular doppler sensor held in a special supporting needle that fits in the straightening cannula for the thermocoagulation needle. After insertion of the straightening cannula aimed at the stereotactic target, the microvascular doppler probe positioned at the tip of a supporting hollow needle is advanced through the cannula. The proximal micrometer gauge indicates the depth of the tip of the doppler probe. By setting the doppler device to the shortest focusing depth (0.1 mm), the maximum pulsatile vascular sound indicates the depth of the vessel. A prominent vascular sound was identified in 3 of 13 cases. By adjusting the depth of the target, no major bleeding was experienced after thermocoagulation lesions were made. This technique secures and protects the fragile microvascular doppler and identifies any significant arterial vessels at the stereotactic target, thus avoiding vascular injury.