Cranial repair is a type of brain surgery to repair the skull for a series of accidental injuries such as traumatic brain injuries (car accidents, or falling from a building) that result in a defect in the skull. The bones of the human head consist of two parts: the cranium and the maxillofacial bones, including 23 flat and irregular bones of different shapes and sizes. Of these, the cranium consists of 8 pieces that protect the body’s commanding part, the brain; the maxillofacial bones are located in the scaffolding that makes up the face, and there are 15 pieces in total. The volume of the skull is fixed, when the loss of bone flap protection, its limitations also disappeared, the cerebral venous return and dural sinus of the external pressure is reduced, the brain parenchyma can be outward expansion, resulting in an increase in the venous return of the cerebral hemispheres, plasma, tissue fluid and other extracellular fluids to increase the absorption of plasma, which causes the brain parenchyma cells to reduce the volume of the brain and the brain to increase the space within the brain and then the expansion of the brain ventricles, which develops into hydrocephalus. Once a skull injury occurs, it is important to pay attention to it, as it can be life-threatening. What is the process of cranial repair? First of all, anesthesia, disinfection, then cut the scalp, expose the bone window, take the preoperative three-dimensional shaping of polyetheretherketone PEEK patch, according to the shape of the patient’s cranial defects to adjust and fixation of the reset, suture the scalp, the operation is completed successfully.