H.‐G. K. Blaas

Surveillance and outcome of fetuses with gastroschisis

Infants with gastroschisis have a high survival rate. However, the rate (10–15%) of intrauterine fetal death (IUFD) is considerable, and the association with fetal distress is well known. The aim of this study was to describe the outcome of fetuses with a prenatal diagnosis of gastroschisis. The impact of correct prenatal diagnosis, surveillance and signs of complicating risk factors were evaluated.

Characteristics and outcome of 90 cases of fetal omphalocele

The aim of this study was to describe the outcome of a case series of fetuses with omphalocele.

Prenatal ultrasound detection of facial clefts: a prospective study of 49 314 deliveries in a non-selected population in Norway

To evaluate prenatal detection of facial clefts by ultrasound examination in a large non‐selected population, and to study trends in detection rates over 18 years, as well as the prevalence of isolated cases and those with associated anomalies.

Imperforate anus: a relatively common anomaly rarely diagnosed prenatally

Despite the relatively common occurrence of imperforate anus, prenatal diagnosis is rarely reported. In this study, we investigated the presence and diagnosis of imperforate anus along with strategies for improving prenatal diagnosis of the condition.

Prenatal ultrasound detection of talipes equinovarus in a non‐selected population of 49 314 deliveries in Norway

To evaluate prenatal ultrasound detection of talipes equinovarus (TEV) in a large non‐selected population and to study trends in detection rates over time, as well as the prevalence and outcome of isolated TEV and TEV with associated anomalies.

3D imaging of the fetal face - Recommendations from the International 3D Focus Group

Three-dimensional and four-dimensional ultrasound (3D/4D US) technology can be easily applied to routine prenatal diagnosis and can provide images of the fetal face that cannot be achieved with two-dimensional ultrasound (2D US) [1–7]. The most recent 3D/4D US technology facilitates the 3D/4D US examinations even for the less trained sonographer and gives the examiner the opportunity to identify the normal and abnormal fetal face in the most appropriate imaging mode [8]. The purpose of publishing these recommendations was to demonstrate the different possibilities of assessing the normal and abnormal fetal face with 3D/4D ultrasound and to give the operator an overview of the benefit resulting from the application of that technology.

Prenatal detection of trisomy 21 by second-trimester ultrasound examination and maternal age in a non-selected population of 49 314 births in Norway

To assess the contribution of the second‐trimester routine ultrasound examination and maternal age (≥ 38 years) to the prenatal detection of trisomy 21 in a large non‐selected population in which no other screening methods were carried out.

Three‐dimensional ultrasound imaging of the fetal skull and face

B. TUTSCHEK1,2* , H.-G. K. BLAAS3, J. ABRAMOWICZ4, K. BABA5, J. DENG6, W. LEE7, E. MERZ8, L. PLATT9, D. PRETORIUS10, I. E. TIMOR-TRITSCH11 and L. GINDES12, for the ISUOG 3D Special Interest Group 1Prenatal Zurich, Zürich, Switzerland; 2Medical Faculty, Heinrich Heine University, Düsseldorf, Germany; 3Department of Laboratory Medicine, Children’s and Women’s Health, Norwegian University of Science and Technology, National Center for Fetal Medicine, St Olavs Hospital, Trondheim, Norway; 4Department of Obstetrics and Gynecology, University of Chicago, Chicago, IL, USA; 5Saitama Medical Center, Saitama Medical University, Kawagoe, Japan; 6University College London, London, UK; 7Baylor College of Medicine, Obstetrics & Gynecology, Houston, TX, USA; 8Krankenhaus Nordwest Centre for Prenatal Diagnosis and Therapy, Frankfurt, Germany; 9Department of Obstetrics and Gynecology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; 10Department of Radiology, University of California San Diego, CA, USA; 11Department of Obstetrics and Gynecology, NYU School of Medicine, New York, NY, USA; 12Department of Obstetrics and Gynecology, Wolfson Medical Center, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel *Correspondence. (e-mail: tutschek@me.com)

3D ultrasound and the fetal palate. Re: Qualitative evaluation of Crystal Vue rendering technology in assessment of fetal lip and palate

Dall’Asta and colleagues have used a new surface rendering algorithm to study the fetal palate1. Any reconstruction algorithm depends on the presence of ‘true-positive’ voxels in the original volume. Reconstruction of data from the fetal hard and soft palate is particularly challenging, because, unlike the lips and the alveolar ridge, it is an internal structure that is easily shadowed by the surrounding bones. Recently, we detailed how such shadowing can produce an artifact, mimicking a cleft palate, unless the volume is acquired appropriately2. The main criteria required to ensure that the primary and secondary palate is contained in an ultrasound volume, using multiplanar reconstruction or surface rendering, are frontal insonation (from either a median or an axial3 approach) and angling of the transducer to avoid shadowing by the alveolar ridge4. These principles and the possible depiction of the entire hard palate are shown in Figure 1. Before any rendering of the palate is attempted, a volume must be scrutinized in multiplanar mode to ensure absence of shadows in the region of interest.

3D to boldly go where no 2D has gone before? Pitfalls in 3D reconstruction of the fetal palate

Dall’Asta et al.1 allege that three-dimensional (3D) ultrasound reconstruction can show structures of the fetal palate where the original volume is devoid of information, stating that ‘shadowing did not prevent palate visualization’. The entire fetal secondary hard palate (the osseous palate internal to the alveolar ridge) can be seen only if there is no shadowing of the space occupied by it. This is independent of the type of reconstruction algorithm and viewing direction (post-processing) and is primarily dependent on the insonation angle during volume acquisition2,3. Dall’Asta et al.1 refer to papers that first described the so-called ‘3D reverse face’ (3D RF) view4 and