Fetal Anatomy Research Articles

VP04.03: Assessment of maternal anxiety among women undergoing an early comprehensive fetal anatomy scan

VP04.03: Assessment of maternal anxiety among women undergoing an early comprehensive fetal anatomy scan

OC10.07: Using artificial intelligence to identify fetal anatomy for biometry: agreement of measurements and estimated fetal weight

OC10.07: Using artificial intelligence to identify fetal anatomy for biometry: agreement of measurements and estimated fetal weight

OC05.10: Three‐dimensional fetal anatomy imaging from 12 to 14 weeks of gestation

OC05.10: Three‐dimensional fetal anatomy imaging from 12 to 14 weeks of gestation

A new two-dimensional sonographic approach to the assessment of the fetal hard and soft palates.

Facial clefts are among the most common congenital defects. Ultrasound (US) imaging of secondary fetal palate, especially the detection of isolated defects, remains challenging. Currently described two-dimensional (2D) and three-dimensional methods are technically demanding and impractical for application during routine fetal anatomy evaluation. As an adjunct method, magnetic resonance imaging can provide additional information but has its limitations. We present a novel 2D US approach using axial and sagittal planes to evaluate the fetal palate and demonstrate the main differences between an intact palate, isolated cleft palate, and a cleft lip with cleft palate.

Twin anemia–polycythemia sequence in sex‐discordant monochorionic dizygotic twins

The possibility of monochorionic (MC) dizygotic (DZ) twins was first raised in 1970. As MC sex-discordant twins are rarely observed, MCDZ twins are seldom recognized clinically. Conception by assisted reproductive technology (ART) is associated with an increased frequency of MC diamniotic (DA) twins, with more than 50% of reported MCDZ twins conceived by ART1. With the increased use of ART, it is therefore reasonable to expect that the incidence of MCDZ twins may increase. MC twins share a single placenta and are connected by the placental circulation. They are at risk of transfusion imbalance in this circulation, which may lead to twin–twin transfusion syndrome (TTTS) or twin anemia–polycythemia sequence (TAPS). The diagnosis of TTTS at an early stage is based on discordant amniotic fluid volume. Currently, the diagnosis of TAPS is based on increased middle cerebral artery peak systolic velocity (MCA-PSV) in the donor twin (> 1.5 MoM) and decreased MCA-PSV in the recipient twin (< 1 MoM)2. Postnatally, TAPS can be diagnosed based on an intertwin hemoglobin difference of > 8 g/dL and at least one of the following criteria: (1) reticulocyte count ratio > 1.7; and (2) presence of only small vascular anastomoses on placental examination3. We report a case of TAPS diagnosed prenatally in a MCDZ twin pregnancy. A 32-year-old woman with a spontaneously conceived pregnancy was diagnosed with a MCDA twin gestation at 14 weeks by ultrasound. Sex discordance was noted on the fetal anatomy survey and was suggested on cell-free fetal DNA screening. Sex discordance was confirmed postnatally. A diagnosis of TAPS was suspected at 28 + 6 weeks based on MCA-PSV (1.65 MoM in the donor and 0.48 MoM in the recipient), and worsening of TAPS, with a new finding of placental echogenicity discordance between the donor and recipient sides, was suspected at 30 + 6 weeks (Figure 1). The patient was delivered at 31 + 2 weeks, following administration of corticosteroids and magnesium sulfate for neuroprotection, due to worsening of TAPS. TAPS was confirmed postnatally. Hemoglobin was 25.2 g/dL in the recipient twin and 7.5 g/dL in the donor twin. Reticulocyte count ratio (donor/recipient twin) was 14.7. Monochorionicity was confirmed by pathological examination. In TAPS, the placenta may have a discordant ultrasound appearance (hyperechoic on the donor twin side and hypoechoic on the recipient twin side) and a color difference on gross examination (pale appearance on the donor twin side and dark purple appearance on the recipient twin side)4. The current case demonstrated these findings (Figures 1 and 2). Although a case of TAPS in MCDZ twins was reported recently in a spontaneously delivered pregnancy in which the diagnosis was made postnatally5, we report what we believe to be the first case of TAPS in MCDZ twins that was diagnosed prenatally. Our report demonstrates that discordant MCA-PSV measurements and placental echogenicity differences in MC twin pregnancy are objective ultrasound findings that may indicate a developing and worsening status of TAPS in MCDZ twins. It is important to recognize that MCDZ twin gestations exist. Early determination of chorionicity during the first trimester with confirmation of fetal sex in the second trimester is the key in identifying a MCDZ twin gestation.

AIUM Practice Parameter for the Performance of Detailed Diagnostic Obstetric Ultrasound Examinations Between 12 Weeks 0 Days and 13 Weeks 6 Days.

AIUM Practice Parameter for the Performance of Detailed Diagnostic Obstetric Ultrasound Examinations Between 12 Weeks 0 Days and 13 Weeks 6 Days.

Feasibility of a fetal anatomy 3D atlas by computer-assisted anatomic dissection

ObjectiveTo assess the feasibility of 3D modelisation of fetal anatomy by using the Computer-assisted anatomic dissection (CAAD) based on immunolabeled histologic slices and MRI slices with a specific 3D software. Study designFor pelvis and lower limbs, subjects came from legal abortion, medical pregnancy termination, or late miscarriage. Specimens were fixed in 10 % formalin, then embedded in paraffin wax and serially sectioned. The histological slices were stained using HES and Masson Trichrome. Protein S-100 and D2−40 markers were used for immuno-labelling. Serial transverse sections were digitalized and manually aligned. Fetal brain slices were obtained from in utero or post-mortem MRI. ResultsCAAD was performed on 10 fetuses: pelvis was modelised with 3 fetuses of 13, 15 and 24 W G, lower limbs with 2 fetuses of 14 and 15 W G and brain with 5 fetuses aged between 19 and 37 W G. Fetal pelvis innervation was analysed after immunolabelling and nerves appeared proportionally bigger than in adults with the same topography. Lower limbs analysis revealed that nerve development was guided by vascular development: the sciatic nerve along the big axial vein, the saphen nerve along the big saphen vein and the sural nerve along the small saphen vein. Fetal brain study allowed to describe the gyration process and the lateral ventricle development. ConclusionCAAD technique provides an accurate 3D reconstruction of fetal anatomy for lower limbs and pelvis but has to be improved for brain model since midline structures were not amendable for analysis. These results need to be confirmed with larger series of specimens at different stages of development.

Abnormalities of the Fetal Central Nervous System: Prenatal US Diagnosis with Postnatal Correlation.

Fetal central nervous system (CNS) abnormalities are second only to cardiac malformations in their frequency of occurrence. Early and accurate diagnosis at prenatal US is therefore essential, allowing improved prenatal counseling and facilitating appropriate referral. Thorough knowledge of normal intracranial anatomy and adoption of a logical sonographic approach can improve depiction of abnormal findings, leading to a more accurate differential diagnosis earlier in pregnancy. Four standard recommended views-transventricular, falx, cavum, and posterior fossa or transcerebellar views-provide an overview of fetal intracranial anatomy during the second trimester anatomy scan. Essential elements surveyed in the head and neck include the lateral cerebral ventricles, choroid plexus, midline falx, cavum septi pellucidi, cerebellum, cisterna magna, upper lip, and nuchal fold. CNS abnormalities can be organized into six main categories at prenatal US. Developmental anomalies include neural tube defects and neuronal migration disorders. Posterior fossa disorders include Dandy-Walker malformation variants and Chiari II malformation. Ventricular anomalies include aqueductal stenosis. Midline disorders include those on the spectrum of holoprosencephaly, agenesis of the corpus callosum, and septo-optic dysplasia. Vascular anomalies include vein of Galen malformations. Miscellaneous disorders include hydranencephaly, porencephaly, tumors, and intracranial hemorrhage. Correlation with postnatal MRI is helpful for confirmation and clarification of suspected diagnoses after birth. The authors discuss a standard US imaging approach to the fetal CNS and review cases in all categories of CNS malformations, providing postnatal MRI correlation when available.©RSNA, 2020.

Strategies for diagnosis of fetal right atrium dilation: based on fetal cardiac anatomy and hemodynamics

BackgroundFetal right atrium (RA) dilation is frequently detected in routine screenings while it remains a challenge to clarify the reasons. This study aimed to analyze the cardiac anatomy and hemodynamics of fetal RA dilation and the changes of hemodynamic indexes.MethodsIn the retrospective study, 420 fetuses with RA dilation were included, which were classified into the physiological group (n = 202), volume overload group (n = 142), and the pressure overload group (n = 76). The ratio of right atrium to left atrium (RA/LA) were measured at four-chamber view. Peak velocity of tricuspid regurgitation (VTR) was recorded in each case, if existed.ResultsThe RA/LA ratio in the volume overload group is significantly higher than both the pressure overload group and the physiological group (both P = 0.000) throughout the pregnancy while no difference presents between the pressure overload group and the physiological group (P = 0.694 for 19–31 GW, and P = 0.974 for 32–36 GW, respectively). The VTR in the pressure overload group (3.29 ± 0.58 m/s) is significantly higher than both the volume overload group (1.85 ± 0.45 m/s, P = 0.000) and the physiological group (0.88 ± 0.45 m/s, P = 0.000). The volume overload group shows a significantly higher VTR than the physiological group (P = 0.000). In the volume overload group, the ductal contraction/closure shows a significantly higher VTR than that in the pulmonary valve stenosis/atresia (3.98 ± 0.41 m/s vs. 3.03 ± 0.38 m/s, P = 0.000).ConclusionsA strategy proposed herein is useful to clarify the reasons for RA dilatation by systematically assessing fetal hemodynamics, which may facilitate the sonographers to make an accurate diagnosis of congenital heart disease.

DEVELOPMENTAL PECULIARITIES OF TOPOGRAPHIC MORPHOLOGY OF CERVICAL FASCIA AND CELLULAR SPACES IN ANTERIOR AND LATERAL CERVICAL REGIONS IN HUMAN FETUSES

In-depth study of the peculiarities of the morphological, topographic and anatomical relationships between fascia, muscles, vessels, nerves, cellular spaces and organs of other parts of the human body requires applying an appropriate methodology of morphological research. According to some researchers, the superficial, pretracheal, and prevertebral plates of the cervical fascia develop depending on the origin and morphogenesis of the respective groups of neck muscles. Obtaining data on the development of topographic morphology of the cervical fascia and interfascial cellular spaces of the anterior and lateral areas of the neck during the fetal period of human ontogenesis is an important area of fetal anatomy and surgery and can be used for age comparison. The purpose of the study was to clarify the peculiarities of the development of the topographic morphology in the cervical fascia and interfascial cellular spaces of the anterior and lateral areas of the neck in human fetuses of 4-10 months of gestation. The study was performed on 75 human fetuses of 81.0-375.0 mm parietal coccygeal length without external signs of anatomical abnormalities or developmental anomalies of the cervical region by preparing microscopic slides of organs and structures of the anterior and lateral areas of the neck. The samples taken from fetuses weighing more than 500.0 g were investigated directly at the Chernivtsi Regional Paediatric Pathological Bureau according to the association agreement. The material was also taken from the M.G. Turkevich Museum of the Human Anatomy Department, Bukovinian State Medical University. The macroscopic and microscopic investigation of the cervical region in human fetuses of 4-7 months revealed thin, semitranslucent plates of the cervical fascia: superficial, middle (pretracheal) and deep (prevertebral). In fetuses of 8-10 months in the anterior area of the neck, the plates of the cervical fascia were clearly seen and shiny. Subcutaneous, or superficial, and intracervical fascias were fascias propria of the neck, and having no clear boundaries passed into adjacent areas. In the fetal period of human ontogenesis the interfascial cellular spaces of the anterior and lateral areas of the neck develop including suprapectoral, anterovisceral, extravisceral, antescalenous, interscalenous cellular spaces and sheath of vascular-nervous bundles of the neck. During the fetal period of human ontogenesis, there is a pronounced variation in the development and location of the plates of the cervical fascia. The authors of this study state that the research and result publication have no conflicts regarding commercial or financial relations, relations with organizations and/or individuals who may have been related to the study.

Outcomes of urinary tract abnormalities diagnosed by the routine third trimester scan

ObjectiveThe aim of this study is to determine the incidence of congenital abnormalities of the kidneys and urinary tract (CAKUT) detected for the first time in an unselected population undergoing a routine third trimester scan between 30–34 week’s gestation. MethodsThis was a retrospective analysis of 8562 routine third trimester ultrasound scans during which the fetal anatomy was evaluated, and, any structural abnormalities detected, recorded onto a fetal database which was subsequently analysed for CAKUT. All postnatal records of antenatally diagnosed CAKUT were obtained and analysed for diagnosis and management. ResultsThere were 26 cases of urological abnormalities detected for the first time in the third trimester. The most frequent abnormality was unilateral renal pelvis dilatation (73%). Postnatal ultrasound confirmed abnormalities in 19 (73%) newborns, with two (8%) resolving antenatally and four (15%) postnatally. The overall incidence of new CAKUT detected by the third trimester scan was 0.22% (19/8562) with a male to female ratio of 1:1.6. Four patients required surgery, two received cystoscopic injection of Deflux with circumcision, one received cystoscopic valve ablation and one patient received a staged hypospadias repair. ConclusionRoutine third trimester scanning is already performed in many countries with proposed benefits primarily directed towards the monitoring of fetal growth and late pregnancy malpresentation. For healthcare systems that still utilize two routine scans, debate is ongoing as to the value of introducing a routine third trimester scan. The ability to detect additional and potentially missed CAKUT is a further benefit, which in isolation is likely of too small an impact to merit implementation. However, the combination of fetal structural assessment, growth velocity monitoring and fetal presentation evaluation presents a strong case for inclusion in an antenatal screening program. The findings of this study highlight the importance of a detailed fetal structural evaluation at each antenatal ultrasound scan.

Delay of Fetal Anatomy Ultrasound Assessment Based on Maternal Body Mass Index Does Not Reduce the Rate of Inadequate Visualization.

To determine whether delay of initial anatomy ultrasound based on the maternal body mass index (BMI) reduces the rate of inadequate visualization compared to standard timing at 180/7 to 196/7 weeks. A retrospective study of singleton anatomy assessments was conducted at a tertiary care center in the 2-year period before (A, 2012-2014) and after (B, 2014-2016) protocol initiation. Assessments in period B were scheduled on the basis of the BMI in the first trimester: lower than 25 kg/m2 , 180/7 to 196/7 weeks; 25 to 29.9 kg/m2 , 190/7 to 206/7 weeks; 30 to 34.9 kg/m2 , 200/7 to 216/7 weeks; 35 to 39.9 kg/m2 , 210/7 to 226/7 weeks; and 40 kg/m2 or higher, 220/7 to 236/7 weeks. In period A, assessments were scheduled between 180/7 and 196/7 weeks. The rate of inadequate visualization and repeated assessments in periods A and B were compared. Multivariable logistic regression, per-protocol, and BMI subgroup analyses were completed. In total, 3491 pregnancies in period A and 3672 in period B were included. In period B, 74% were scheduled per protocol; however, this rate decreased for higher-BMI categories (52% for BMI ≥40 kg/m2 ). The inadequate visualization rate was slightly higher in period B versus A (16.9% versus 15.0%; P = .03) and exceeded 35% for a BMI of 40 kg/m2 or higher, with or without delay. After adjusting for maternal age and fetal presentation, period B had small increased odds of inadequate visualization versus period A (adjusted odds ratio, 1.2; 95% confidence interval, 1.02-1.38). Repeated assessment rates were similar in periods B and A (14.0% versus 13.1%; P = .25). In pregnancies with obesity, a protocol delaying the initial assessment beyond 196/7 weeks based on the maternal BMI does not reduce the rate of inadequate visualization.

Sonographic detection of fetal abnormalities before 11 weeks of gestation.

Sonographic detection of fetal abnormalities before 11 weeks of gestation.

Evaluation of the Relationship Between Placental Thickness and Obstetric Doppler Parameters During the Second Trimester

OBJECTIVE: To determine whether there is a relationship between placental thickness and the umbilical artery and uterine artery Doppler evaluation in the second trimester. STUDY DESIGN: The placental thickness and the umbilical artery and uterine artery Doppler evaluations were recorded by a single operator for patients who were admitted for an obstetric follow-up or fetal anatomy screening at 18-28 gestational weeks. The relation between these variables was investigated by evaluating the patients only once.RESULTS: In our study, the mean placental thickness was 31.7 (SD±8.01) mm. The umbilical artery Doppler parameters did not correlate with the placental thickness. The uterine artery Doppler systolic/diastolic velocity, Pulsatility index and Resistance index values positively correlated with the placental thickness. However, these correlations were not statistically significant. CONCLUSIONS: Although there was no relationship between the placental thickness and obstetric Doppler parameters in this study, we suggest that they are likely important factors and their significance should be evaluated in future studies

Diagnosis of fetal defects in twin pregnancies at routine 11–13‐week ultrasound examination

To examine the performance of the routine 11-13-week scan in detecting fetal defects in twin pregnancies and to examine if, in pregnancies with a fetal defect, compared to those with normal fetuses, there is increased incidence of nuchal translucency thickness (NT) ≥ 95th and ≥ 99th percentiles or intertwin discordance in crown-rump length (CRL) ≥ 10% and ≥ 15%. This was a retrospective analysis of prospectively collected data in twin pregnancies undergoing routine ultrasound examination for fetal anatomy, according to standardized protocols, at 11-13 weeks' gestation between 2002 and 2019. Pregnancies with known chromosomal abnormality were excluded. The final diagnosis of fetal defect was based on the results of postnatal examination in cases of live birth and on the findings of the last ultrasound examination in cases of pregnancy termination, miscarriage or stillbirth. The performance of the 11-13-week scan in the detection of fetal defects was determined. The study population of 6366 twin pregnancies with two live fetuses at 11-13 weeks' gestation included 4979 (78.2%) dichorionic (DC) and 1387 (21.8%) monochorionic (MC) twin pregnancies. The main findings were: first, the overall incidence of fetal defects was higher in MC than in DC twins (2.8% vs 1.3%); second, the proportion of defects diagnosed in the first trimester was higher in MC than in DC twins (52.6% vs 27.1%); third, the pattern of defects in relation to detectability at the 11-13-week scan (always detectable, sometimes detectable and never detectable) was similar to that reported previously in singleton pregnancies; fourth, always-detectable defects included acrania, alobar holoprosencephaly, encephalocele, pentalogy of Cantrell, exomphalos, body-stalk anomaly, twin reversed arterial perfusion sequence and conjoined twins; fifth, the incidence of fetal NT ≥ 95th percentile was higher in those with than in those without a defect (16.5% vs 4.5% in DC twins and 19.2% vs 5.9% in MC twins) and this was also true for NT ≥ 99th percentile (8.3% vs 1.0% in DC twins and 15.4% vs 2.0% in MC twins); and sixth, the incidence of CRL discordance ≥ 10% was higher in those with than in those without a defect (20.2% vs 7.9% in DC twins and 33.8% vs 9.3% in MC twins) and this was also true for CRL discordance ≥ 15% (10.1% vs 1.9% in DC twins and 28.2% vs 2.8% in MC twins). First, fetal defects are more common in MC than in DC twin pregnancies. Second, first-trimester detection of fetal defects in DC twin pregnancies is similar to that in singleton pregnancies. Third, first-trimester detectability of defects in MC twins is higher than in DC twins. Fourth, in twin pregnancies with a fetal defect, there is higher intertwin discordance in CRL and incidence of increased NT, but the predictive performance of screening by these markers is poor. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Abortion for fetal indications: Timing of prenatal diagnosis and abortion for structural and genetic abnormalities

ObjectiveTo compare diagnoses in patients undergoing abortion for fetal indications at 15–0/7 to 21–6/7 vs. ≥22–0/7 weeks’ gestation. Study designThis retrospective cohort study included women undergoing abortion at ≥15–0/7 weeks’ gestation for fetal indications from 2012 to 2018 at our institution. We compared indications (genetic vs. structural only) between groups by gestational age (15–0/7 to 21–6/7 vs. ≥22–0/7 weeks). We performed statistical analysis using Fisher’s exact and Mann-Whitney U tests. ResultsThe 158 women identified included 97 (61.4%) at 15–0/7 to 21–6/7 and 61 (38.6%) at ≥22–0/7 weeks’ gestation. Women at an earlier gestational age more commonly had an initial diagnosis of a genetic disorder (41 [42.3%)] vs.10 [16.4%], respectively, p < .001). In 69 cases with initial or subsequent diagnosis of a genetic disorder, there were differences in the types of genetic abnormalities, with common chromosomal abnormalities (including Trisomies 13, 18, and 21) the most frequent diagnosis in those who underwent abortion at 15–0/7 to 21–6/7 weeks and microarray abnormalities more common at ≥22–0/7 weeks (22 [44.9%] vs. 4 [18.2%]) and 7 [14.9%] vs. 11 [50.0%], respectively, p = .01). Routine ultrasonography for fetal anomaly surveillance occurred one week earlier in women undergoing abortion for structural anomalies at 15–0/7 to 21–6/7weeks (median 19–2/7 weeks [interquartile range (IQR) 19 0/7 to 19–5/7 weeks]) compared to ≥22–0/7 weeks (median 20–2/7 weeks [IQR 19 6/7 to 20 4/7 weeks]), p < .001. ConclusionAbortions for genetic indications are performed earlier in gestation compared to those performed for structural abnormalities. Timing of fetal anatomy ultrasound examination correlated with gestational age at abortion for structural abnormalities. ImplicationsMany states impose gestational-age based abortion bans, with 20-weeks post-fertilization the most common. However, we may not identify fetal abnormalities until close to 22 weeks gestation (20-weeks post-fertilization). Optimizing timing of prenatal diagnosis might mitigate the impact of gestational-age based abortion bans.

Excerpts From the World Medical Literature: Obstetrics.

Summary: This was a prospective cohort study of 52 400 singleton pregnancies having a routine obstetric sonogram at 350 to 366 weeks gestation in one tertiary care centre in the United Kingdom over a 5-year period. The authors aimed to determine the incidence and types of fetal anomalies detected for the first time in the late third trimester. All patients had the routine second trimester sonogram between 180 and 240 weeks gestation, and 90% of the study population also had a first-trimester scan between 110 and 130 weeks gestation. Pregnancies resulting in a live birth or stillbirth were included, yet those with known aneuploidy were excluded. Ultrasound assessments were performed or supervised by sonographers certified by the Fetal Medicine Foundation. The medical specialists became involved on detection of abnormalities. Although the 350- to 370-week scan was principally done for assessments of fetal growth, fluid volume, and Doppler interrogations of the uterine, umbilical, and middle cerebral arteries, sonographers were also requested to assess fetal anatomy as they would at the routine 180- to 240-week anomaly scan.

Fetal Anatomy of the Optic Strut and Prechiasmatic Sulcus with a Clinical Perspective

The main objective of the study was to show the morphologic features of optic strut (OS) and prechiasmatic sulcus (PS) in the fetal skull base with a surgical anatomical perspective. Twenty-three fetal cadavers (9 female, 14 male) with an average age of 21.70 ± 3.12 (range: 16-28) weeks of gestation in the inventory of the Anatomy Department were included in the study. Measurements were made with a digital image analysis software and goniometer. The sulcal length, interoptic distance, planum length, and sulcal angle were detected as follows: 3.91 ± 0.74 mm, 6.88 ± 1.04 mm, 6.55 ± 1.51 mm, and 24.52 ± 9.51°, respectively. Considering the location of the posteromedial margin of OS according to PS, OS was identified as the sulcal in 56.5% (13 cases), postsulcal in 30.4% (7 cases), and asymmetric in 13% (3 cases). According to the sulcal length and angle, PS was identified as type 1 in 26.1% (6cases), type 2 in 21.7% (5 cases), type 3 in 30.4% (7cases), and type 4 in 21.7% (5 cases). Our findings suggest that the sulcal length and angle reach adult size in utero. Taking into account the fetal and the gathered adult measurements, the high percentage of steep angle compared to flat angle show that after birth, PS become more flat, probably depending on the variations of the sphenoid sinus pneumatization. Thus, more studies conducted on the alterations in PS and OS types relative to the pneumatization are needed in terms of patient positioning, selection of appropriate surgical approach, and intraoperative decision-making.

Three-Dimensional Printing of Fetal Models of Congenital Heart Disease Derived From Microfocus Computed Tomography: A Case Series.

This article presents a case series of n = 21 models of fetal cardiovascular anatomies obtained from post mortem microfocus computed tomography (micro-CT) data. The case series includes a broad range of diagnoses (e.g., tetralogy of Fallot, hypoplastic left heart syndrome, dextrocardia, double outlet right ventricle, atrio-ventricular septal defect) and cases also had a range of associated extra-cardiac malformations (e.g., VACTERL syndrome, central nervous system anomalies, renal anomalies). All cases were successfully reconstructed from the microfocus computed tomography data, demonstrating the feasibility of the technique and of the protocols, including in-house printing with a desktop 3D printer (Form2, Formlabs). All models were printed in 1:1 scale as well as with the 5-fold magnification, to provide insight into the intra-cardiac structures. Possible uses of the models include education and training.

Fetal Echo: Application of Four Chamber View and Additional Views in Obstetrics Anomaly Scan and Third Trimester Low-Risk Pregnancy

This article presents a step-wise process to evaluate fetal cardiac anatomy by the radiologist and the pediatric cardiologist, to become more familiar while assessing the four chamber view including the views for the outflow tracts. The additional views include bicaval view, three-vessel view (3VV), three- vessel trachea view (3VT), and aortic arch view. M-mode, color flow mapping and pulse Doppler ultrasound are useful to evaluate cardiac anatomy and function. If the heart does not look normal, the patient should be referred to dedicated fetal echo centre for detailed evaluation. Ductus venosus Doppler, cardiovascular profile score and visualization of thymus in 3-vessel view have also been described in brief.