Routine screening for fetal limb abnormalities in the first trimester.

OBJECTIVE: We aim to determine the accuracy of first-trimester ultrasonography in detecting fetal limb abnormalities. METHODS: This is a retrospective study of all women undergoing fetal nuchal translucency (NT) assessment and detailed fetal anatomic survey in the first trimester at a single tertiary-care referral center in China. Fetal anatomy scans were repeated in the second trimester. Detection of fetal limb abnormalities was compared between first and second trimester anatomy scans and confirmed at delivery or at autopsy. RESULTS: Analyzed were 9438 fetuses from 9197 women (241 twin pairs). The incidence of fetal limb abnormalities was 0.38% (36/9438). Of these, 28 (77.8%) were diagnosed prenatally: 23 (63.9%) on first trimester scan and 5 (13.9%) on second trimester scan. Limb reduction defects (usually transverse limb deficiencies) were the most common limb defects identified in the first trimester (n = 12), followed by clubfoot (n = 4), skeletal dysplasia (n = 3), sirenomelia (n = 1), limb dysplasia (n = 1), malposition (n = 1), and syndactyly (n = 1). Nine fetuses with isolated limb abnormalities had normal NT, while 74.1% (20/27) of limb abnormalities that were associated with other abnormalities had increased NT. CONCLUSIONS: This study demonstrates that the majority of limb abnormalities detected prenatally [23/28 (82%)] can be identified in the first trimester, especially major limb defects; however, our numbers are small and still need larger cases for further investigation.

Prenatal diagnosis and perinatal outcome of congenital dacryocystocele: a large case series.

OBJECTIVE: To describe the incidence, prenatal diagnosis, and perinatal outcome in fetuses with congenital dacryocystocele. METHODS: All cases of congenital dacryocystocele diagnosed by prenatal ultrasound were identified using an established perinatal database. Prenatal ultrasound images were reviewed, and perinatal outcome was abstracted from the medical records. The correlation between the cyst size, gestational age, and prenatal and neonatal outcome was analyzed. RESULTS: The overall incidence of fetal dacryocystocele was 0.016% (75/456,202). Fifty-three cases (70.7%) had unilateral, and 22 (29.3%) had bilateral lesions. Lesions were seen more commonly among female fetuses with a female : male ratio 1.48 : 1. The average diameter of cysts size was 6.9 ± 1.9 mm (3.3-11 mm). There was a direct correlation between cyst size and gestational age. Among the 75 cases, 8 were lost to follow-up, 3 underwent elective termination of pregnancy. 58 resolved spontaneously before birth, and 6 were confirmed at birth. Two developed neonatal infection requiring antibiotic treatment. All 6 cases confirmed at birth resolved without surgical resection. CONCLUSIONS: Congenital dacryocystocele can be diagnosed by prenatal ultrasound. Such lesions typically resolve spontaneously in utero or in the early neonatal period. Thus, it should be considered as a developmental variant rather than a structural birth defect.

[Ultrasound measurement of fetal posterior fossa at 11 to 13⁺6 gestational weeks for screening open spina bifida].

OBJECTIVE: To establish the normal reference ranges of transabdominal ultrasound measurements of the posterior fossa structure in fetuses at 11 to 13⁺6 gestational weeks and explore their clinical value in screening open spina bifida (OSB). METHODS: Between January, 2013 and September, 541 randomly selected normal fetuses underwent nuchal translucency at the gestational age 11 to 13⁺6 weeks. The parameters of the posterior fossa were measured in mid-sagittal view of the fetal face and the axial view of the transverse cerebellum insonated through the anterior fontanel by transabdominal ultrasound to establish the normal reference ranges. The measurements were obtained from 3 fetuses with OSB for comparison with the reference ranges. RESULTS: In normal fetuses, the parameters of the posterior fossa measured in the two views showed no significant differences (P>0.05). Two high echogenic lines were observed in normal fetuses, as compared with one in fetuses with OSB representing the posterior border of the brain stem and the anterior border of the fourth ventricle. The line between the posterior border of the fourth ventricle and the anterior border of the cisterna magna was not displayed in fetuses with OSB. The anteroposterior diameters of the brain stem, the fourth ventricle, and cisterna magna all increased in positive correlation with the crown-lump length in normal fetuses. In the 3 OSB fetuses, the anteroposterior diameter of the brain stem exceeded the 95th percentile and the anteroposterior diameter of fourth ventrical-cisterner magena was below the 5th percentile of the reference range for CRL; the brain stem to fourth ventrical-cisterner magena anteroposterior diameter ratio was increased to above 1. CONCLUSION: The established normal reference ranges of the parameters of fetal posterior fossa may provide assistance in early OSB detection. The absence of the posterior border of the fourth ventricle and the anterior border of the cisterna magna and a brainstem to fourth ventrical-cisterner magena anteroposterior diameter ratio greater than 1 can be indicative of OSB at 11 to 13⁺6 gestational weeks.