Pedro Teixeira Castro1, Heron Werner1, Edward Araujo Júnior2. 1. Department of Radiology, Clínica de Diagnóstico por Imagem (CPDI), Rio de Janeiro, RJ Brazil. 2. Department of Obstetrics, Paulista School of Medicine, Federal University of São Paulo (EPM-UNIFESP), Rua Belchior de Azevedo, 156 apto. 111 Torre Vitoria, São Paulo, SP CEP 05089-030 Brazil.