Objective

CASE SERIES Case 1A 30-year-old woman was referred at 13 + 1 weeks' gestation for first-trimester screening. The fetus had a crown-rump length (CRL) of 72 mm and a nuchal Figure 1 The mid-sagittal view is the best plane for evaluating intracranial translucency (IT) and the posterior brain region. This ultrasound image in a 13-week fetus illustrates the landmarks typical of a normal examination. The thalamus (Th) and brainstem (BS) have a hypoechoic appearance. The fourth ventricle, also called the IT, appears as an anechoic region with two horizontal echogenic borders, allowing reliable identification: the anterior border of the IT is the posterior border of the BS, and the posterior border of the IT is the choroid plexus (Chor. plex.) of the fourth ventricle. The choroid plexus is a well-recognized structure floating in the fluid of the IT and the future cisterna magna (f.CM), which are still connected to one another. The brainstem-occipital bone distance (BSOB) appears larger than does the brainstem diameter itself. OB, occipital bone. translucency thickness (NT) of 1.7 mm. Routine examination of the posterior brain failed to show the expected normal anatomy (Figure 1) 1,2 ; instead the brainstem appeared thickened and shifted backward toward the occipital bone (Figure 2), such that the ratio of brainstem diameter to brainstem-occipital bone distance (BS/BSOB ratio) was increased 3 , with a value of 1

Objective To describe the morphology of the frontal bones and metopic suture at 9-34 weeks of gestation using three-dimensional (3D)

Objectives To assess whether, at 11-13-week and mid-trimester ultrasound

No abstract

Objective

Congenital ichthyosis, otherwise known as harlequin fetus, is a severe, generally lethal, anomaly. Prenatal diagnosis is usually possible in families at risk but requires invasive fetoscopy for skin biopsy. The application of three-dimensional ultrasound enables a greatly improved analysis of the facial morphology and thus provides an important contribution to prenatal diagnosis. Although such three-dimensional diagnostic procedures are performed in specialized centers, sonographers should be aware of the signs observed at routine two-dimensional ultrasound examination in order to ensure appropriate referral for diagnosis. We describe two consecutive pregnancies of the same parents in which two- and three-dimensional ultrasound were used in the prenatal diagnosis of harlequin fetus.

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