Prenatal diagnosis of scalp cyst with spontaneous regression.

Fetal scalp cysts are rare, and they may be easily misdiagnosed as meningoceles or encephaloceles. A 38-year-old pregnant woman was referred to our hospital for ultrasound examination, which revealed a small cyst above the skull with no defect in the skull. The cyst could not be seen on follow-up ultrasound examinations. After delivery, a three-dimensional CT scan of the head revealed no defect in skull and scalp. Fetal scalp cysts usually require surgical excision after birth, but can regress without any treatment.