Definition and Characteristics - Cystic hygroma is an abnormal growth that appears on a baby's neck or head. - It consists of one or more cysts that tend to grow larger over time. - The disorder usually develops while the fetus is still in the uterus but can also appear after birth. - Cystic hygroma is also known as cystic lymphangioma and macrocystic lymphatic malformation. - It is a congenital lymphatic lesion with multiple locules filled with lymph.

Benign Nature and Associations - Cystic hygromas are benign but can be disfiguring. - It usually affects children, but rarely can be present in adulthood. - It is associated with nuchal lymphangioma or fetal hydrops. - It can be associated with Down syndrome, Turner syndrome, or Noonan syndrome. - Cowchock-Wapner-Kurtz syndrome is a lethal version that includes cystic hygroma, cleft palate, and lymphedema.

Signs and Symptoms - Cystic hygromas are classically found in the posterior triangle of the neck. - They are increasingly diagnosed by prenatal ultrasonography. - A common sign is a neck growth that may be found at birth or later in an infant. - Cystic hygromas can grow very large and may affect breathing and swallowing. - Other body parts like the mouth, cheek, tongue, arms, chest, legs, groin, and buttocks can also be affected.

Diagnosis - Lymphatic malformations can be detected by ultrasound during pregnancy. - Further investigation, such as amniocentesis, may be done to evaluate for genetic abnormalities. - Postnatal or incidental findings during medical imaging can also lead to the diagnosis. - Imaging techniques like ultrasound or MRI can provide more information about the size and extent of the lesion. - Multiple cystic masses can arise in children, requiring verification of the diagnosis.

Treatment - Babies with prenatally diagnosed cystic hygromas should be delivered in a major medical center. - Cesarean section may be performed for large cystic hygromas. - Close observation by a neonatologist is recommended after birth. - Thin needle aspiration may be used to reduce the volume of the cystic hygroma. - Surgical removal of the cystic hygroma may be necessary, but recurrence is possible depending on the extent of the condition.