Antenatal imaging of cutis verticis gyrata.

Cutis verticis gyrata (CVG) is a skin condition characterized by thick folds and deep furrows, resembling a cortical gyral pattern. There is a recognized but rare association with Noonan syndrome. We report the antenatal imaging, including three-dimensional surface-rendered sonography and MRI, of a fetus with CVG who was subsequently diagnosed with Noonan syndrome. The case illustrates the antenatal appearances of congenital CVG and the potential yield of antenatal imaging in excluding a major central nervous system anomaly. This is important because without prior knowledge of this condition and its imaging characteristics, it is possible to get a false impression of an underlying skull defect on mid-trimester imaging.