[Contribution of ultrasonography to the study of retroperitoneal tumors in children (author's transl)].

: Ultrasonography investigations of retroperitoneal tumors in children were conducted in 25 cases: 11 nephroblastomas, 11 neuroblastomas, 2 ganglioneuromas, and 1 rhabdomyosarcoma. Ultrasonographic exploration of such tumors should include analysis of the mass: echostructure, limits, interfaces and dimensions, and analysis of its extension. The latter should determine the position in relation to the median line, the condition of the large vessels (inferior vena cava and aorta), the homolateral renal cavities and the contralateral kidney, and the presence or absence of glandular spread and hepatic metastases. The semiology of each of these elements is described and discussed, to determine their individual diagnostic value.