IDENTIFICATION AND LOCALIZATION OF INTRACEREBRAL VESSELS BY MICROVASCULAR DOPPLER IN STEREOTAXIC PALLIDOTOMY AND THALAMOTOMY - TECHNICAL NOTE

OBJECTIVE: To identify intracerebral vessels in proximity to the targe t for thermocoagulation in functional neurosurgery, we use a microvasc ular doppler sensor held in a special supporting needle that fits in t he straightening cannula for the thermocoagulation needle. TECHNIQUE: After insertion of the straightening cannula aimed at the stereotactic target, the microvascular doppler probe positioned at the tip of a su pporting hollow needle is advanced through the cannula. The proximal m icrometer gauge indicates the depth of the tip of the doppler probe. B y setting the doppler device to the shortest focusing depth (0.1 mm), the maximum pulsatile vascular sound indicates the depth of the vessel . RESULTS AND CONCLUSION: A prominent vascular sound was identified in 3 of 13 cases. By adjusting the depth of the target, no major bleedin g was experienced after thermocoagulation lesions were made. This tech nique secures and protects the fragile microvascular doppler and ident ifies any significant arterial vessels at the stereotactic target, thu s avoiding vascular injury.