Abstract: | Hyperpneumatization of the temporal bone with extension into the occipital bone and even the parietal bones is a rare condition. According to a review of the literature, it mostly appears unilaterally in men and on the right side. Often it is discovered when complications like pneumatocele or pneumocephalus appear. The authors review and analyze all reported cases of hyperpneumatization, its symptoms, complications and treatment. We present a patient with extensive pneumatization found in the mastoid process, temporal bone, occipital bone and both parietal bones, who was discovered accidentally. The cause of the extension of pneumatization into the occipital and parietal bone is probably incomplete closure of the occipitomastoid synchondrosis and lambdoid and sagital sutures, which usually close in early adulthood and later, even in the 30s. Asymptomatic patients should be aware of possible complications, and in case of complications, operative therapy is often indicated. |