N. Cernea

Improved detection rate of structural abnormalities in the first trimester using an extended examination protocol

To assess the potential of first‐trimester sonography in the detection of fetal abnormalities using an extended protocol that is achievable with reasonable resources of time, personnel and ultrasound equipment.

First trimester two‐ and four‐dimensional cardiac scan: intra‐ and interobserver agreement, comparison between methods and benefits of color Doppler technique

To evaluate intra‐ and interobserver agreement for first‐trimester fetal cardiac structural assessment, using two‐dimensional (2D) ultrasound (2D‐US) and 4D‐US (4D spatiotemporal image correlation (STIC) technology), to compare the methods and to assess the advantages of adding color Doppler to each technique.

Right aortic arch with patent right ductus arteriosus and normal heart

The term ‘right aortic arch’ (RAA) refers to a congenital abnormal position of the aortic arch, that is, to the right of the trachea, with or without an abnormal branching pattern, and is one of the least frequently prenatally diagnosed cardiac abnormalities1–3. The main clue for the detection of RAA in large population studies and small case series has been absence of the normal ‘V’shaped confluence of the ductal and aortic arches (both to the left of the trachea) in the axial three vessels and trachea (3VT) view1–7, as a RAA and left ductus form an abnormal ‘U’-shape. Reviewing papers that have evaluated the associated conditions and outcomes of the different types of RAA, its occurrence with a right ductus arteriosus (RDA) has been reported with severe cardiac anomalies (tetralogy of Fallot, pulmonary atresia with ventricular septal defect, common arterial trunk)3,7,8 and high rates of 22q11 deletions7,9,10. We describe here a case of RAA with a RDA in which the heart was normal. This was easily recognizable in the 3VT view from the first trimester onwards, independent of the angle of insonation. Sonographic evaluations and image acquisitions were performed transabdominally using a Voluson 730 ultrasound machine (GE Medical Systems, Zipf, Austria). A 31-yearold low-risk pregnant woman, gravida 1 para 0, attended for first-trimester screening at our center. A cardiac transverse sweep showed an anatomically and functionally normal fetal heart, but a right-sided aortic arch and a V-shaped confluence with a patent RDA were observed on the 3VT view (Figure 1). Offline analysis by examiners experienced in fetal echocardiography resulted in similar conclusions. Invasive tests ruled out karyotype and 22q11 abnormalities. During the second and third trimesters normal views of the fetal heart were found on the standard axial approach (situs, area, axis, cardiac chambers, emergence of great vessels) (Figures 2a–c and Videoclip S1) and, in accordance with previous findings, an RAA and patent RDA were identified as a V-shaped

Quantification of fetal head direction using transperineal ultrasound: an easier approach

Ultrasound offers several advantages for planning and monitoring labor, being a safe, non-invasive and easyto-learn technique, which offers accurate and objective information, even in difficult clinical situations. Several linear measurements (progression distance and head-toperineum distance) and angles (head direction (HD), progression angle and middle-line angle), have been shown to be useful in the estimation of fetal head progression1–10. The rationale for assessing HD during the second stage of labor is the curvilinear path of fetal head descent, directed initially downward then horizontally and finally upward, that can be easily tracked in the sagittal transperineal view. Alone or in combination with other ultrasound parameters, HD has proved useful in the prediction of vaginal and successful operative delivery4,10. The abovementioned linear and angle assessments can be obtained in a semiautomatic manner, using threedimensional ultrasound11, but this is not widely available for use on the labor ward, requires additional skills to perform and has not been shown to provide further benefit over two-dimensional ultrasound12. Most of these linear distances and angles can be determined quickly and simply by measuring a single angle (progression angle, middle-line angle), a single distance (head-to-perineum distance) or a combination of a 90◦ angle and a line (progression distance). However, a recent systematic review13 does not wholly support the use of ultrasound in labor and there is an argument that some measures are too complicated. For example, for quantification of HD, first the maternal reference parameter, the infrapubic line (IL), is drawn perpendicular to the symphysis pubis long axis (SPla), starting from the inferior symphyseal margin. Then the fetal parameter, the widest head diameter, is traced. Fetal head descent with respect to the pubic symphysis and IL is evaluated by drawing a line perpendicular to the widest diameter of the fetal head, i.e. HD. Finally, this parameter is quantified by measuring the direction angle (DA) between the IL and the HD11,14. In some studies4,10, HD is classified in this final step in relation to the SPla: ‘head up’ (when it points ventrally at an angle of > 30◦), ‘head down’ (when this angle is < 0◦) and ‘horizontal’ (when this angle is 0–30◦). We propose an easier assessment of DA, by reducing the number of steps in the protocol. In Figure 1 we show how the classical measurement is equivalent to the angle between the fetal biparietal diameter and SPla. Thus, the steps described above can be substituted by the measurement of one angle between two lines similar, for example, to measurement of the fetal cardiac axis (Figure 2). Increasing values of this angle signify

Agenesis of ductus venosus in sequential first and second trimester screening

The goal of this study is to evaluate the potential of first trimester (FT) screening in the diagnosis of agenesis of the ductus venosus (ADV) and to study its prevalence in a low‐risk population, the associated conditions, and pregnancy outcome.

P25.03: Relation between nuchal translucency thickness and prevalence of chromosomal defects, miscarriage, fetal death and major fetal abnormalities

Objective: To determine whether Doppler velocimetry of the ductus venosus can improve the predictive capacity of increased nuchal translucency in the detection of trisomy 21 at 11–14 weeks of gestation. Methods: Ductus venosus Doppler ultrasound blood velocity waveforms were obtained prospectively at 11–14 weeks of gestation in 2280 consecutive singleton pregnancies. Waveforms were classified either as normal in the presence of a positive A-wave, or as abnormal if the A-wave was absent or negative. All cases were screened for chromosomal defects by a combination of maternal age and fetal nuchal translucency thickness. Concerm TN, a Down sindromy was suspected when the nuchal translucency was above the 95th centile. In 344 cases karyotyping was performed. Results: Down syndrome was found in 37 cases. On basis in the NT the overall detection rate, specificity, positive predictive value, negative predictive value and likelihood ratio for trisomy 21 were 85.7%, 97.1%, 99.9%, 28% and 44.9% respectively. On basis in the ductus venosus blood flow during atrial contraction the sensitivity, specificity, the negative and positive predictive values and likelihood ratio were 82.9%, 98.8%, 99.7%, 56.9%, 69% respectively. Conclusions: Enlarged nuchal translucency and abnormal ductus venosus blood flow are useful markers of trisomy 21 in the first trimester ultrasound screening, assessment of ductus venosus blood flow velocimetry could improve the predictive for the detection of Down syndrome.

P13.03: Correlations of the sonopartogram with classic clinical partogram and key points from a pilot study

Objectives: To determine if the degree of caput impacts the accuracy of assessing fetal position in labour when completed by third and fourth year obstetrics residents. Methods: Assessment of fetal position during labour was performed by third and fourth year residents when patients were 8 cm dilated or more, had ruptured membranes, and the gestation was 35 weeks or greater. The residents performed digital examinations for location and axis of fetal sutures and fontanelles in order to determine the orientation of the fetal brow and occiput. Ultrasound assessment was performed immediately following resident examination. Residents were blinded to ultrasound findings. Assessments were considered correct if within 15 degrees of ultrasound findings. Transabdominal and transperineal scanning with a 3.5mHz abdominal probe were utilised. Caput was measured at the time of transperineal ultrasound and grouped into no/mild (0-0.99 cm), moderate (1.0-1.99 cm), and marked (2cm+) caput. Chi-squared analysis was performed using SPSS. Results: Twelve residents assessed 143 labouring women. Mean maternal age was 26.4 years (SD 6.2), mean gestational age was 39.3 weeks (SD 1.2), and 42% had a history of a vaginal delivery. Maternal ethnicity was 60.1% black, 35.7% Caucasian, and 4.2% ‘‘other.’’ The overall accuracy of the resident exams was 47.9%. The amount of caput widely varied from 0 to 3.10 cm, with the largest number having 1.0-1.99 cm of caput. Caput did not change the accuracy of assessment of fetal position (table 1). Conclusions: Degree of caput did not play an important role in the ability to assess fetal position of sutures and fontanelles by palpation.

OP14.06: Finding the hippocampus: challenge accepted

G. Kasprian2, G.M. Gruber1, G. Dovjak2, D. Bettelheim3, C. Haberler4, D. Prayer2 1Department for Anatomy, Centre of Anatomy and Cell Biology, Vienna, Austria; 2Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria; 3Department of Fetomaternal Medicine, Medical University of Vienna, Vienna, Austria; 4Institute of Neurology/Neuropathology, Medical University of Vienna, Vienna, Austria

OC05.01: Reliability of first trimester structural sonographic extended evaluation

J. Degenhardt1, R. Schürg2, A. Kawecki3, M. Pawlik1, C. Enzensberger1, R. Stressig4, R. Axt-Fliedner1, T. Kohl3 1Division of Prenatal Medicine, University of Giessen and Marburg, Giessen, Germany; 2Department of Anesthesiology, University of Giessen and Marburg, Giessen, Germany; 3German Center for Fetal Surgery & Minimally Invasive Therapy, University of Giessen and Marburg, Giessen, Germany; 4University Hospital of Bonn, Bonn, Germany

OP11.01: Assessment of fetal 3D volumes at 11–13 + 6 weeks

Objectives: Part of the SONOSEROSCREEN project, at the end of the first trimester – 11–13+6 weeks, we are assessing the risk of chromosomal abnormalities and also make a primary assessment of fetal morphology. We investigated to what extent the aquision of a 3D ultrasound volume at the double test (combined test) can provide enlightening information on fetal morphology. Methods: During May 2010–December 2010 there were saved 72 3D volumes that were processed off-line for assessing the morphological parameters of the standard 11–13+6 weeks SONOSEROSCREEN ultrasound protocol. Ten parameters have been chosen as a benchmark for evaluation: the correct view of NT, the intracranial translucency and orbits, the choroid plexus, position of the fetal heart, the diaphragm, the image of the stomach, bladder, umbilical cord insertion and assessment of the four limbs. There were accepted for study only the volumes obtained in ideal conditions–a standard position for nuchal translucency measurement, the transducer facing the fetus and the interposition of amniotic fluid to ensure good quality images. Results: Images obtained by off-line manipulation of 3D volumes allowed us to obtain reference images in over 90% of cases–comparable to the 2D examination. Conclusions: Off-line examination allows a careful analysis of the morphology from 11 to 13+6 weeks, without the pressure of a conclusion ‘‘on the spot’’. It does not exceed the time devoted to the evaluation of 2D and the conclusion may be offered to the patient with the combined test result.