例1,孕妇,25岁,孕23+6周。产前超声检查:胎头位于耻骨联合上方,胎儿颅内、颜面部、脊柱、胸腹部、胎盘、羊水量、和胎心均未见异常,追踪扫查显示胎儿双足形态异常,双足足底平面和小腿胫腓骨长轴切面在同一切面内显示(图1),三维表面成像显示胎儿双足呈内翻畸形(图2),连续观察胎儿下肢的运动,该姿势仍未恢复正常。超声诊断:中孕单活胎;胎儿双足内翻畸 Example 1, pregnant women, 25 years old, 23 weeks pregnant + 6 weeks. Prenatal ultrasound: the fetal head located above the pubic symphysis, fetus intracranial, facial, spine, chest and abdomen, placenta, amniotic fluid volume, and fetal heart rate were no abnormalities, follow-up scan showed abnormal fetal bipedal, bipedal foot The bottom plane and the tibiofibular long axis view are shown in the same section (Figure 1). Three-dimensional surface images show a varus of the fetus (Figure 2), and the posture of the lower limbs of the fetus is continuously observed. The posture has not returned to normal. Ultrasound diagnosis: single live birth in pregnancy; fetal bipedal inversion