患儿，男．smo，因患支气管肺炎人院。父母非近亲婚配，母孕期正常。其母孕7n。o时腹部I3超示胎儿腹腔囊性占位。生后3mo时13超示腹腔内探及（l．0X9．3X3．2）cm大小无回声暗区、边界清，左管大小可，浆膜光滑，集合系统无分离扩张，实质内回声均质，右肾未探及。腹部B超示左 Children, men. smo, suffering from bronchial pneumonia hospital. Parents non-relatives marriage, normal pregnancy during pregnancy. The mother’s pregnancy 7n. o Abdomen I3 Abdominal Cystic Placement 3mo at 13mo post-abdomen showed intra-abdominal exploration and (l.0X9.3X3.2) cm size echo-free dark area, the boundary clearance, the left tube size can be, smooth serosal, the collection system without separation and expansion, the essence of the echo within the homogeneous , The right kidney is not explored. Abdominal B ultrasound shows left