Aplasia cutis congenita: management of a large skull defect with acrania.

Aplasia cutis congenita is a rare disorder characterized by absence of skin. Lesions typically occur on the vertex and are sometimes small, but they can affect deep tissues such as the skull bone and dura. Mortality is related to the depth and size of the lesion and can amount to a rate of more than 50% when full thickness is involved.