Complex sentence: A MRI scan of the brain may be performed (under anesthesia) on infants who have a port-wine stain in the head area in order to check for signs of Sturge-Weber syndrome.
Split into simpler sentences: A MRI scan of the brain may be performed (under anesthesia) on infants who have a port-wine stain in the head area. This is done to check for signs of Sturge-Weber syndrome.