Congenital defect of skin, bone and/or dura at the vertex of the scalp, ranging from a minor area of skin that lacks hair follicles to an extensive wound of the scalp with exposed brain. Aplasia cutis can be an isolated defect or part of a syndrome.
Treatment is largely directed by the extend of the defect. If surgery is required, one should be aware of abnormal vascular perfusion of the scalp, making rotation flaps unreliable.