RESUMO
Near infrared spectroscopy (NIRS) technology is frequently used to measure regional cerebral tissue oxygen saturation (rSO2). The measurement of rSO2 has diverse range of clinical application for its easy bed-side applicability, continuous monitoring, interpretation and valuable information on cerebral oxygenation. However, it also has few technical limitations; absorption by skull tissues, presence of hematomas, and other pigments such as melanin, bilirubin can affect the rSO2 measurements and thus interfere with the accuracy of monitoring. We report a case wherein low values of frontal rSO2 normalized after evacuation of bilateral fronto-temporo-parietal (FTP) chronic subdural hematoma (CSDH) in a patient with bilateral internal carotid artery (ICA) stenosis.