Prenatal ultrasonic diagnosis of retroperitoneal cystic lymphangioma

A 31 year old white woman, gravida 5, para 4, was exam· ined at 36.5 weeks of fetal development because of a nonreactive nonstress test. Sonographic examination revealed a male fetus. A cystic septated mass was seen in the left lower quadrant of the fetal abdomen, displacing the fetal bladder to the right (Fig. 1). An amniocentesis was per~ formed, and the results indicated pulmonary maturity. A cesarean section was done. The baby's 1 and 5 minute Apgar scores were 8 and 9, respectively. Physical examination showed a palpable, soft, cylindrical midline mass in the lower abdomen and pelvis. A postnatal sonogram confirmed the presence of a complex cystic mass measuring 7.3 x 3.4 x 3.7 cm, with multiple thin septations (Fig. 2). Mild right-sided hydronephrosis also was seen. Differential considerations included lymphangioma, mesenteric cyst, duplication cyst, and cystic teratoma. Plain films of the abdomen and a small bowel series showed displacement of loops of bowel out of the pelvis and left lower abdomen. A barium enema demonstrated straightening and right-sided