Objectives: We aimed to determine associated ultrasonographic findings, chromosome abnormalities and the prognostic factors of cystic hygromas in live-born infants.
Methods: We reported a series of 57 cystic hygroma cases, who were diagnosed in the first and the second trimester of pregnancy by means of the ultrasonographic morphology of cystic hygroma, associated structural abnormalities, karyotype analysis and the autopsy findings. Survivors were followed for their fetal outcome and prognosis.
Results: There were 57 new cases of cystic hygroma among 8,155 screenings (0.7%). 35 of the cases (61.4%) were nonseptated and 22 of the cases (38.6%) were septated cystic hygroma. Chromosomal abnormalities were found in 23 of the cases (40.3%). The most common abnormality in nonseptated cystic hygroma was trisomy 21 (8 cases, 25%) and in septated cystic hygroma was Turner syndrome (4 cases, 21.1%). The most common associated structural malformations were cardiac abnormalities (in 7 cases, 20%) in nonseptated cystic hygroma cases and nonimmune hydrops (in 12 cases, 54.5%) in septated cystic hygroma cases. Overall survival was poor; only one case of septated cystic hygroma with axillary location and seven cases of nonseptated cystic hygroma, of whom two died in the neonatal period, were alive (10.5%). This study had 80% power to detect 0.03% difference in diagnosis cystic hygroma (alpha = 0.05, beta = 0.80).
Conclusion: Fetuses with cystic hygroma are at high risk for adverse outcome. Prenatal diagnosis with invasive procedures should be done in order to inform the parents in detail. Axillary location of the hygroma and the depth of invasion had prognostic importance.