Early diagnosis of a fetal skeletal dysplasia associated with increased nuchal translucency with 2D and 3D ultrasound

We report a case of the prenatal diagnosis of a lethal skeletal dysplasia in a fetus presenting With increased nuchal translucency of 7.3 mm on a routine first trimester scan at 12 weeks of gestation. The karyotype was normal and there was no history of previous affected pregnancies. An abnormality of the fetal spine was first seen at 12 weeks of gestation, the malformation of the left hemithorax, where the processus transversi and the costal bones were replaced by a cystic structure, was detected at 13 weeks using a combination of two- and three-dimensional ultrasound. In order to identify correctly the underlying problem, at 16 weeks of gestation a detailed 2D and 3D ultrasound examination was performed. 3D surface images were calculated and a combination of surface reconstruction and maximum-mode for clear delineation of the fetal skeleton was used. In this way, the vertebral defects with absence of costal bones and processus transversi in the region of the left hemithorax, which were replaced by a cystic structure causing thoracic kyphoscoliosis and pulmonal hypoplasia and were associated with marked ventriculomegaly, could be clearly demonstrated. Although fetal autopsy was not carried out, the underlying abnormalities diagnosed by ultrasound suggest Jarcho-Levin syndrome as final diagnosis, which is characterized by multiple vertebral and rib malformations.