Prenatal Diagnosis of Fetal Cystic Hygroma Using Three-dimensional Ultrasound in 2000–2011

Prenatal diagnosis of cystic hygroma (CH) is very important to clinical management in fetal medicine. To date, ultrasound is the best tool for prenatal diagnosis. With recent advances in technology, three-dimensional ultrasound (3D US) contributes substantially to the prenatal diagnosis of CH. In this series, we reported our work of detecting fetal CH by 3D US from July 2000 to December 2011. We reviewed our computer database of prenatal diagnosis of CH in National Cheng Kung University Hospital. All the fetuses were initially scanned by two-dimensional US to locate the region-of-interest. The 3D probe was used to scan all the regions of interest systematically and mechanically, and all the images were stored on laser discs for further 3D visualization and reconstruction. In total, 85 cases of fetal CH were diagnosed in utero. The range of gestational age at prenatal diagnosis by 3D US was between 9 and 27 weeks (mean: 14.1 weeks), and 55 cases were diagnosed before 14 weeks (65%). Only three cases were diagnosed after 21 weeks (4%). In 20 fetuses with karyotping, 11 (55%) had chromosomal abnormalities. In 11 fetuses with aneuploidy, eight (73%) had Turner syndrome (45, X). Forty-three cases (51%) of CH were complicated with hydrops fetalis, and 20 (24%) were complicated with other additional structural abnormalities. In conclusion, 3D US can add novel visual depiction of a 3D lesion of CH after reconstruction, and is helpful in prenatal diagnosis and genetic consultation of CH. Furthermore, the trend analysis in this series showed significantly earlier gestational age at prenatal diagnosis of CH than a decade ago.