A sonographic study of fetal cystic hygromas

Fetal cystic hygromas are fluid filled sacs of lymphatic origin occurring in the posterolateral neck. Based on an experience with 15 of these hygromas diagnosed antenatally, the various sonographic appearances are illustrated and differential diagnostic features are discussed. A midline septum or hydrops may serve as diagnostic clues. The sonographic and anatomic features of a hygroma are correlated using a gelatin embedding technique.