ETIOLOGY, PROGNOSIS AND MANAGEMENT OF NUCHAL CYSTIC HYGROMA - 25 NEW CASES AND LITERATURE-REVIEW

Objective: To develop an algorithm for the prenatal management of pati ents when a cystic hygroma is diagnosed by ultrasonography. Methods: W e report a personal series of 25 cases diagnosed between 10 and 23 wee ks gestation and a review of the literature comprising a total of 999 cases. We focused on the etiologies and the value of various prognosti c factors in the management of cystic hygromas. These include karyotyp e, alpha-fetoprotein levels, sonographic findings in the fetus and wit hin the hygroma itself, and natural history. Results: According to the literature, fetal chromosomal abnormalities were associated with cyst ic hygromas in 62% of the cases. Turner's syndrome remains the most co mmon (33%) but Down's syndrome, Trisomy 18 and Trisomy 13 are not rare (15, 7 and 2%). Others have Mendelian abnormalities. The prognosis re mains gloomy. The literature reports that only 9% of cases result in h ealthy children with normal karyotypes. The remaining 91% are either t erminated (89%) or liveborn (2%), but with chromosome abnormalities or various malformations. Conclusion: The prognostic factors associated with a poor outcome are an abnormal karyotype and associated structura l malformations. Resolution of the hygroma by 20 weeks gestation sugge sts a good prognosis, but is not definitive. All other factors evaluat ed do not appear to be of prognostic value at this time. Careful analy sis of these prognostic factors is very important to identify the smal l percentage of normal children and to advise parents effectively for a future pregnancy. Copyright (C) 1997 Elsevier Science Ireland Ltd.