External ear reconstruction is a surgical revision for congenital deficiencies in the ear contour, or the lack of an external ear. Full auricular reconstruction encompasses a high degree of technical difficulty in plastic surgery, and its difficulty lies in the fact that it involves the cutting of skin flaps, fascial flaps, rib cartilage, the sculpting of cartilage scaffolds, and skin implants. A realistically shaped auricle needs to be as thin and coquettish as or close to a normal ear, and moreover, it needs to have a realistic sense of three-dimensionality. The following are the methods of external ear reconstruction: I. Expansion flap method of external ear reconstruction 1, Phase I surgery: skin expansion of mastoid area. A 50ml skin expander is implanted under the skin of the mastoid area and the skin is slowly expanded with water. The purpose of this procedure is to expand the hairless skin of the mastoid area for covering the ear scaffold, and to better reveal the contours of the reconstructed ear with the thinned skin. 2. Phase II surgery: The outer ear is reconstructed using the expanded flap. The second stage surgery is performed 2 months after the first stage surgery. In other words, the outer ear is reconstructed by taking autologous rib cartilage, sculpting it into an ear scaffold, and then using the expanded skin to cover the ear scaffold. The procedure takes about 2 weeks. 3. The third stage of surgery: ear eye and ear screen shaping, and local scar revision. This procedure is performed six months after the second stage surgery. The ear screen is reconstructed using the remaining small ear tissue, and the ear eye is deepened and the scar behind the ear is repaired. There is also the dilated flap method of ear reconstruction, which involves embedding an 80ml dilator under the skin of the mastoid area, overdeveloping the skin for a long period of time, taking about 3 to 4 months, and injecting about 140ml of water. The second-stage surgery completely wraps the ear scaffold with the expanded skin to form a well-defined and well-formed auricle. II. Non-expansion method of external ear reconstruction (Brent-Nagata method) It was first applied abroad and later introduced into China. The indications for surgery are limited, but the method is simple and the efficacy is real. 1. Phase I surgery: subcutaneous grafting of ear scaffold. In other words, autologous rib cartilage is taken, sculpted into an ear scaffold, and then the ear scaffold stent is implanted under the skin in the mastoid area, and the reconstructed outer ear and the skull are tightly attached without an otocranial sulcus. The procedure takes about 2 weeks. 2. Phase II surgery: otocranial sulcusplasty. This is performed four months to six months after the first stage surgery, in which the reconstructed ear is lifted from the scalp to build an otocranial sulcus and form a three-dimensional reconstructed ear. The procedure takes 2 weeks. 3. Third stage surgery: ear eye deepening, and local scar revision. This is a simpler procedure than the third stage of expanded flap auricular reconstruction. This surgery is mainly adapted to patients with higher hairline (i.e. larger hairless skin in the mastoid area), thinner and more elastic skin, and a relatively small normal auricle. Otherwise, only expanded flap auricular reconstruction can be done. Advantages and disadvantages of the two methods 1. The expanded flap method is suitable for all patients, although the effect is exact, the course of skin expansion is long, and complications are likely to occur. It often affects the study and work of children and parents due to the long treatment course. 2, Brent-Nagata method has a small range of indications, not all patients can be used, only those patients with hairless skin in the mastoid area, thin skin and good elasticity, and the operation is simple and not prone to complications. If the indications are chosen appropriately, the results do not differ from the former and do not interfere with the study work of the child’s parents because the course of each operation is shorter.