What Does This PNS X-ray Result Indicate?

My son who is 41/2 years old was getting throat irritation, throat pain, and assoicated ear pain, which leads to moderate to high fever, with medications it subsides for few days and then the entire episode repeats again. Now my doctor advised to take chest xray and PNS X-ray. Chest x ray is normal but PNS xray shows mild haziness in bilateral sinuses. what does this mean. is this the cause of his repeated throat irritations and fever. Please advise.