 Retrospective studies have shown that surgery in infancy is associated with worse neurodevelopmental outcome, compared to general population. The reasons may be complex, and patients at risk are unknown. Brain growth and central nervous system formation are extremely active in neonates and infants. Metabolic or circulatory derangement may have negative influence on the developing brain. Disease and perioperative period, both may further put this population at risk for physiological abnormalities. Near infrared spectroscopy was shown to be a convenient method for monitoring of cerebral tissue oxygenation during surgery. 