INTRAOPERATIVE APPLICATION OF THERMOGRAPHY IN EXTRACRANIAL-INTRACRANIAL BYPASS SURGERY

Abstract
The extracranial-intracranial bypass may have the potential to improve hemodynamic cerebral ischemia caused by occlusive diseases of the main cerebral arteries. Intraoperative confirmation of effective distribution of blood flow via the donor arteries to the involved region will assure a successful bypass surgery. Infrared thermography was used to measure the temperature of the cortical surface at the operative field. Regional cerebral blood flow (rCBF) was measured with a laser Doppler flow meter. Changes in the cortical surface temperature before and after temporary occlusion of the bypass were compared with changes in rCBF values in the corresponding sites. Thermographic examination demonstrated a heterogeneous increase of cortical surface temperature caused by the blood flow via the extracranial-intracranial bypass and was closely related to rCBF changes. Thermography is useful not only to demonstrate the distribution of blood flow through the extracranial-intracranial bypass but also to quantitatively evaluate the rCBF changes in the operative field.