Serial CT Imaging in a Male Child at Different Ages Demonstrating the Three Types of External Occipital Protuberance

The external occipital protuberance (EOP) is a prominent bony elevation located in the posterior midline of the outer surface of the occipital bone, which can be classified into three types based on morphology. Herein, we present the case of a male child who showed all three types at different life stages. A male pediatric patient born in Beijing, China, in 2008 underwent cranial CT examinations at ages 8, 12, and 16 years for different clinical indications. Volume rendered (VR) postprocessed images revealed a dynamic evolutionary process of the EOP morphology, sequentially presenting as the smooth (Type I), wave‐peak (Type II), and spine‐like (Type III) types. We believe this is the first reported case in which a single patient fully exhibited all three types of EOP.