Sonographic Findings in a Case of Tetrasomy 9p Associated with Increased Nuchal Translucency and Dandy-Walker Malformation

We report a case of a 23-year-old pregnant woman, who underwent amniocentesis after ultra-sound (US) examination in the first trimester which revealed a nuchal translucency thickness of 2.9 mm. Cytogenetic analysis revealed complete tetrasomy of the short arm of chromosome 9. Further US evaluation in the second trimester revealed Dandy-Walker malfor-mation, ventriculomegaly, bilateral clubfoot, lip and palate clefts, arthrogryposis and hyperechoic kidneys with bilateral pelvic dilatation. At 30 weeks of gestation, a placental abruption was noted and a Cesarean sec-tion was performed. The infant died shortly after birth. A review of previous cases of tetrasomy 9p shows that the remarkable sonographic findings are ventriculome-galy, intrauterine growth restriction, genitourinary anomaly, Dandy-Walker malformation, cleft lip/palate and limb malformation, but the association of tetras-omy 9p and increased nuchal translucency had not been reported.