294 THE EAR Outstanding Auricle or 'Bat-ear* Many infants and young children appear to have unduly prominent ears but this feature becomes less striking with development of the mastoid process. In marked cases a plastic operation may be performed. It is insuffi- cient to excise only an elliptical area of skin from the posterior aspect of the auricle and mastoid process, because the elasticity of auricular cartilage will cause the deformity to recur. The area of cartilage to be excised is deter- mined by pressing the auricle back into a normal position so that a rounded convexity is produced where the fold of the antihelix should normally be present. This convexity is marked by a line on the lateral surface of the Fig* 164. Haematoma of auricle. Fig. 165. Perichondritis of auricle. auricle, and the situation of this line transferred to the cranial surface by transfixion at several points (.Fig. 163). An elliptical area of skin is removed, the cartilage is incised along the marked line and a crescentic area of carti- lage is dissected out, preserving perichondrium where possible. The wound is sutured and the head bandaged in an effort to prevent haematoma formation. Congenital Aural Fistula This is an opening which, when present, is usually found in front of the helix or tragus, and leads to a fine blind canal. The orifice may become blocked with the result that a fluctuating swelling forms, and abscess forma- tion may occur. The fistula is the remains of the outer or lateral part of the first branchial cleft. Abscess formation is treated by antibiotics, and recurrences may demand the excision of the fistulous track after an injection of aniline dye to outline its course.