Evaluation of the Tramline Sign in the Prediction of Placenta Accreta Spectrum and Perioperative Outcomes in Anterior Placenta Previa.

PURPOSE: To evaluate perioperative outcomes and the prognostic role of the tramline sign in a cohort of women with anterior placenta previa. MATERIALS AND METHODS: Retrospective analysis of 3D ultrasound volumes from women with anterior placenta previa who underwent ultrasound examination beyond 32 weeks. 3D and 3D color volumes were obtained from a sagittal section of the uterus bisecting a partially full bladder and processed using Crystal Vue and Crystal Vue Flow rendering to look for the "tramline sign". "Partial obliteration" was defined as a loss of some or part of the uterine-serosal interface and "full obliteration" as when both interfaces were interrupted. Postnatal ascertainment of placenta accreta spectrum (PAS) was confirmed by findings recorded intraoperatively or on a pathology report. RESULTS: 65 cases were included. The tramline sign was "partially" (17) or "fully" (19) obliterated in 36 cases (55.4 %), and present in 29 (44.6 %). Obliteration was associated with earlier gestational age at delivery (35 + 1 (26 + 3-38 + 3) vs. 36 + 4 (25 + 3-38 + 0) weeks, p = 0.005), greater estimated blood loss (800 (400-11 000) vs. 600 (300-2100) mls, p = 0.003), longer operative time (155 (60-240) vs. 54 (25-80) minutes, p < 0.001), higher rate of hysterectomy (97.2 % vs. 0.0 %, p < 0.001), longer postoperative admission (7 (3-19) vs. 3 (1-5) days, p < 0.001) and a 100 % rate of postnatal diagnosis of PAS. The finding of an "obliterated" tramline sign identified all women that required hysterectomy and all cases of PAS. CONCLUSION: A "partially or fully obliterated" tramline sign is strongly associated with indicators of operative complexity, the postnatal confirmation of PAS, and the need for peripartum hysterectomy.

How to obtain diagnostic planes of the fetal central nervous system using three-dimensional ultrasound and a context-preserving rendering technology.

The antenatal evaluation of the fetal central nervous system (CNS) is among the most difficult tasks of prenatal ultrasound (US), requiring technical skills in relation to ultrasound and image acquisition as well as knowledge of CNS anatomy and how this changes with gestation. According to the International Guidelines for fetal neurosonology, the basic assessment of fetal CNS is most frequently performed on the axial planes, whereas the coronal and sagittal planes are required for the multiplanar evaluation of the CNS within the context of fetal neurosonology. It can be even more technically challenging to obtain "nonaxial" views with 2-dimensional (2D) US. The modality of 3-dimensional (3D) US has been suggested as a panacea to overcome the technical difficulties of achieving nonaxial views. The lack of familiarity of most sonologists with the use of 3D US and its related processing techniques may preclude its use even where it could play an important role in complementing antenatal 2D US assessment. Furthermore, once a 3D volume has been acquired, proprietary software allows it to be processed in different ways, leading to multiple ways of displaying and analyzing the same anatomical imaging or plane. These are difficult to learn and time consuming in the absence of specific training. In this article, we describe the key steps for volume acquisition of a 3D US volume, manipulation, and processing with reference to images of the fetal CNS, using a newly developed context-preserving rendering technique.

Fetal abdominal cysts: antenatal course and postnatal outcomes.

Background There is little information on which to base the prognostic counselling as to whether an antenatally diagnosed fetal abdominal cyst will grow or shrink, or need surgery. This study aims to provide contemporary data on prenatally diagnosed fetal abdominal cysts in relation to their course and postnatal outcomes. Methods Fetal abdominal cysts diagnosed over 11 years in a single centre were identified. The gestational age at diagnosis and cyst characteristics at each examination were recorded (size, location, echogenity, septation and vascularity) and follow-up data from postnatal visits were collected. Results Eighty abdominal cysts were identified antenatally at 28+4 weeks (range 11+0-38+3). Most (87%) were isolated and the majority were pelvic (52%), simple (87.5%) and avascular (100%). Antenatally, 29% resolved spontaneously; 29% reduced in size; 9% were stable and 33% increased in size. Forty-one percent of cysts under 20 mm diameter increased in size, while only 20% of cysts with a diameter of over 40 mm increased in size. The majority of cysts were ovarian in origin (n=45, 56%), followed by intestinal (n=15, 18%), choledochal (n=3, 4%), liver (n=2, 3%) and renal/adrenal origins (n=2, 3%), respectively. In 16% (n=13), the antenatal diagnosis was not obvious. Seventy-five percent of the cysts that persisted postnatally required surgical intervention. Conclusion Most antenatally diagnosed fetal abdominal cysts were ovarian in origin. Though most disappeared antenatally, nearly three quarters required surgical intervention when present after birth. Cysts of intestinal origin are more difficult to diagnose antenatally and often require surgery.

The Brain Shadowing Sign: A Clue Finding for Early Suspicion of Craniosynostosis?

Antenatal imaging of craniosynostosis mainly relies on the demonstration with 2D ultrasound of the abnormal contour of the calvarium and of the loss of hypoechogenicity of the synostotic sutures and on indirect signs of premature closure of the skull sutures; however, isolated craniosynostosis is detected only sporadically at prenatal ultrasound. In this article, we present the first case to our knowledge in which the "brain shadowing sign," a recently described indirect sign of craniosynostosis, noted at 24 weeks in a structurally normal fetus, was the first clue for the diagnosis of isolated bilateral coronal craniosynostosis, which became evident at late gestation.

Etiology and Prognosis of Severe Ventriculomegaly Diagnosed at Late Gestation.

OBJECTIVES: We sought to assess the causes and outcomes of severe VM diagnosed de novo after 24 weeks of gestation where a mid-trimester anomaly scan was described as normal. METHODS: Multicenter retrospective study of five European fetal medicine centers. The inclusion criteria were normal anatomy at the mid-trimester scan, uni/bilateral finding of posterior ventricle measuring ≥ 15 mm after 24 weeks with neonatal and postnatal pediatric and/or neurological assessment data. RESULTS: Of 74 potentially eligible cases, 10 underwent termination, the outcome was missing in 19 cases and there was 1 neonatal death. Therefore, 44 formed the study cohort with a median gestation at diagnosis of 32 + 0 weeks (25 + 6 - 40 + 5). VM was unilateral in five cases. Agenesis of the corpus callosum (ACC) and grade III/IV intraventricular hemorrhage (IVH) accounted for 14 cases each. ACC was isolated in 9 fetuses. Obstructive abnormalities included 5 arachnoid and 1 cavum velum interpositum cyst. Four fetuses had an associated suspected or confirmed genetic condition, 2 congenital infections, 1 abnormal cortical development and the etiology was unknown in 3/44. Postnatal assessment at median 20 months (3 - 96) showed 22/44 (50 %) normal, 7 (16 %) mildly abnormal and 15 (34 %) severely abnormal neurodevelopmental outcomes. CONCLUSION: One half of babies with severe VM diagnosed after 24 weeks have normal infant outcome with ACC and IVH representing the most common causes. Etiology is the most important factor affecting the prognosis of fetuses with severe VM diagnosed at late gestation.

Quantitative analysis of fetal facial morphology using 3D ultrasound and statistical shape modeling: a feasibility study.

BACKGROUND: The antenatal detection of facial dysmorphism using 3-dimensional ultrasound may raise the suspicion of an underlying genetic condition but infrequently leads to a definitive antenatal diagnosis. Despite advances in array and noninvasive prenatal testing, not all genetic conditions can be ascertained from such testing. OBJECTIVES: The aim of this study was to investigate the feasibility of quantitative assessment of fetal face features using prenatal 3-dimensional ultrasound volumes and statistical shape modeling. STUDY DESIGN: Thirteen normal and 7 abnormal stored 3-dimensional ultrasound fetal face volumes were analyzed, at a median gestation of 29+4 weeks (25+0 to 36+1). The 20 3-dimensional surface meshes generated were aligned and served as input for a statistical shape model, which computed the mean 3-dimensional face shape and 3-dimensional shape variations using principal component analysis. RESULTS: Ten shape modes explained more than 90% of the total shape variability in the population. While the first mode accounted for overall size differences, the second highlighted shape feature changes from an overall proportionate toward a more asymmetric face shape with a wide prominent forehead and an undersized, posteriorly positioned chin. Analysis of the Mahalanobis distance in principal component analysis shape space suggested differences between normal and abnormal fetuses (median and interquartile range distance values, 7.31 ± 5.54 for the normal group vs 13.27 ± 9.82 for the abnormal group) (P = .056). CONCLUSION: This feasibility study demonstrates that objective characterization and quantification of fetal facial morphology is possible from 3-dimensional ultrasound. This technique has the potential to assist in utero diagnosis, particularly of rare conditions in which facial dysmorphology is a feature.

Perinatal- and procedure-related outcomes following radiofrequency ablation in monochorionic pregnancy.

OBJECTIVE: We sought to assess the efficacy, complication rates, and outcomes for complex monochorionic pregnancies undergoing selective fetal reduction using radiofrequency ablation (RFA). STUDY DESIGN: In this prospective observational study, 100 consecutive cases of selective fetal reduction using RFA were analyzed. All cases were managed at the Centre for Fetal Care at Queen Charlotte's and Chelsea Hospital in London. Indications for offering RFA, details of the procedure, and pregnancy outcomes were collected and analyzed. RESULTS: The main indications for RFA were discordant fetal anomaly and twin-twin transfusion syndrome. Overall live birth rate was 78% and the median gestation at delivery was 35.15 weeks. Delivery <32 weeks' gestation occurred in 17.9% of cases. Postprocedure abnormal antenatal magnetic resonance imaging occurred in 3% of cases. There was no statistical difference in outcomes with regard to gestation when the procedure was performed or the indication for the RFA. CONCLUSION: RFA appears to be a reasonable option for selective fetal reduction in complex monochorionic pregnancies with an overall survival rate of 78%.

Outcome following selective fetal reduction in monochorionic and dichorionic twin pregnancies discordant for structural, chromosomal and genetic disorders.

BACKGROUND: To investigate the indications for offering selective fetal reduction in monochorionic (MC) and dichorionic (DC) twins and to correlate obstetric outcome with the antenatal procedure. METHODS: All cases of MC and DC twins discordant for structural anomalies and for chromosomal/genetic abnormalities were included. Selective reductions performed for twin-to-twin transfusion syndrome or growth restriction were excluded. For DC twins, feticide was achieved using intracardiac injection of potassium chloride (KCl). For MC twins, bipolar cord occlusion (BCO), interstitial laser or radiofrequency ablation (RFA) was used. RESULTS: There were 121 twin pregnancies discordant for structural and chromosomal abnormalities. Only 88 (56 were MC twins and 32 were DC twins) had selective reduction. For both MC and DC twins, the leading indication for selective reduction was structural anomalies with CNS malformations the most common. For all MC fetal reduction techniques, the overall pregnancy loss rate (<24 weeks) was 8.9% with RFA having the lowest procedure loss rate (7.7%). The preterm delivery rate was lowest with reduction in DC pregnancies. The live birth rates for MC twins were >87% and 100% for DC twins. CONCLUSIONS: Selective reduction in MC pregnancies carries an increased procedure-related and preterm delivery rate compared with DC pregnancies. The main indication for selective reduction was structural malformations, with a predominance of CNS anomalies.

Perinatal outcomes of fetal echogenic bowel.

OBJECTIVE: To investigate perinatal outcomes of fetal echogenic bowel (FEB). METHOD: This is a retrospective observational study of FEB cases from Jan 2005-Dec 2010. Data from ultrasound and fetal medicine investigations, uterine artery Doppler (UAD), intra-partum care and neonatal outcome were obtained from Fetal Medicine, Obstetric and Neonatal Databases. RESULTS: There were 139 cases presenting at 21(+5) (15(+1) -35(+5) ) weeks gestation. Overall, 106/139 (76.2%) were live born (LB), 8/139 (5.8%) were complicated by intra-uterine deaths (IUD), 11/139 (7.9%) had termination of pregnancy (TOP) and 14/139 (10.1%) were lost to follow-up after 28 weeks gestation. Six had chromosomal/genetic abnormalities, two had congenital cytomegalovirus, none had cystic fibrosis.Uterine artery Doppler was normal in 106/130 (81.5%) cases. In this group, there were no cases of fetal growth restriction (FGR), 95/106 (89.6%) were LB, 1/106 (0.94%) had an IUD. In the abnormal UAD group, 17/24 (70.1%) developed FGR, 11/24 (45.8%) were LB, 4/24 (16.7%) had TOP, 7/24 (29.2%) had IUD.In total, 20/106 (18.9%) live births were admitted for specialist neonatal care, 12/20 (60%) for prematurity. Only one had primary bowel pathology. CONCLUSION: Pregnancies with FEB and screen positive UAD are at risk of adverse perinatal outcome. Primary bowel pathology is rare following the finding of FEB.

Postnatal outcome of prenatally diagnosed severe fetal renal pelvic dilatation.

OBJECTIVE: We correlated the prenatal severity with the postnatal outcome of prenatally detected renal pelvic dilatation (RPD). METHODS: Cases of prenatally detected RPD referred between January 2002 and December 2008 were included. Severe RPD was defined as an anterior-posterior diameter of 15 mm, mild and moderate dilatation was defined as 6 to <10 mm and 10 to <15 mm, respectively. Postnatal diagnosis, the need for surgery and the correlation with the prenatal severity was ascertained. RESULTS: Of the 762 patients with RPD, 492 (64.5%) were mild, 167 (21.9%) were moderate, and 103 (13.5%) were severe. The male:female ratio for the severe cohort was 5:1. Of the sever cases, 68% had progressive dilatation. Of the mild/moderate cases, 5% progressed to severe dilatation. PUJ obstruction was confirmed in 48 cases (60.8%), severe VUR in 11 cases (14%), VUJ obstruction in 5 cases (6%), PUV in 2 cases (2.5%), and a nonidentifiable cause in 13 cases (16.5%). Ten of the 48 (20.8%) babies with PUJ obstruction required surgery within the first year of life. CONCLUSION: An obstructive cause is usually present in severe cases, which are more likely to require surgery if there is PUJ obstruction. A high male:female ratio was present in this group.

Accuracy of prenatal diagnosis and prediction of lethality for fetal skeletal dysplasias.

OBJECTIVES: We reviewed all cases with fetal skeletal dysplasia and correlated the accuracy of prenatal diagnoses with the final post-mortem, radiological, or molecular diagnoses. The accuracy of prenatal prediction of lethality was also reviewed. METHODS: All cases of fetal skeletal dysplasia referred between October 2002 and August 2010 were reviewed. Perinatal outcome, the accuracy of prenatal diagnosis, and prediction of lethality were ascertained. Lethality was suspected when significant thoracic narrowing, severe micromelia, multiple fractures, or long bone bowing was present. RESULTS: There were 40 cases of skeletal dysplasia. Thirty-nine (97.5%) were singletons and one (2.5%) was a dichorionic twin pregnancy. Twenty-eight (70%) pregnancies were terminated, five (12.5%) were stillborn, and only seven (17.5%) cases were live born. A final diagnosis was established in 28 (70%) cases. In 29 cases with a presumptive prenatal diagnosis, this was confirmed in 23 (79.3%) cases postnatally. Lethality was predicted with 100% certainty. CONCLUSION: We report higher prenatal/postnatal concordance rates in this series. A precise prenatal diagnosis is frequently difficult and often inaccurate. Prediction of lethality is much easier and often possible with accuracy. Parents need to be aware that the outcome of many skeletal dysplasias is poor.

Fetal transverse limb defects: case series and literature review.

PURPOSE: To investigate the incidence and outcome of antenatally diagnosed isolated transverse limb defects at a major tertiary center and to review the literature relevant to this rare condition. METHODS: This was a retrospective review of all cases (2000-2009) diagnosed with an isolated transverse limb defect referred to a tertiary fetal medicine center. Isolated transverse limb defects were defined as partial or complete absence of a part of one or more limbs in the absence of other abnormalities. RESULTS: Nine cases were identified. The upper limbs were affected in seven cases. The median gestational age at diagnosis was 22+5 weeks (range 21-29 weeks). The defects ranged from absence of digits to the absence of three limbs in one case. Four women opted to have termination of pregnancy. Postnatal and postmortem examination confirmed the ultrasound findings. No obvious risk factors could be identified in the majority of cases. CONCLUSIONS: Most cases of limb defects are believed to be secondary to a vascular insult occurring early in embryonic life. The reason for upper limb predominance remains unclear. Perinatal outcome in this series was poor with the majority of pregnancies terminated. Long-term functional outcome depends on the severity of the limb reduction defect.

Evaluation of perioperative complications using a newly described staging system for placenta accreta spectrum.

INTRODUCTION: The antenatal diagnosis of placenta accreta spectrum (PAS) is in large part subjective and based on expert interpretation. The aim of this study was to externally evaluate a recently developed staging system based on specific and defined prenatal ultrasound (US) features in a cohort of women at risk of PAS undergoing specialist prenatal US, in particular relating to surgical morbidity at delivery. MATERIALS AND METHODS: Database study of cases with confirmed placenta previa. In all, the placenta was evaluated in a systematic fashion. PAS was subclassified in PAS0-PAS3 according to the loss of clear zone, placental lacunae, bladder wall interruption, uterovesical hypervascularity and increased vascularity in the parametrial region. RESULTS: 43 cases were included, of whom 33 had major placenta previa. 31 cases were categorized as PAS0; 3, 4 and 5 cases as PAS1, PAS2 and PAS3, respectively. All women underwent caesarean section and hysterectomy was required in 10. The comparison of the perinatal outcomes among the PAS categories yielded greater operative time (50 (35-129) minutes for PAS0 vs 70 (48-120) for PAS1 vs 95 (60-150) for PAS2 vs 100 (87-180) for PAS3, p < 0.001) and estimated blood loss (800 (500-2500) mls for PAS0 vs 3500 (800-7500) for PAS1 vs 2850 (500-7500) for PAS2 vs 6000 (2500-11000) for PAS3, p < 0.001) for the highest PAS categories, which were also associated with a higher rate of hysterectomy (p < 0.001), blood transfusion (p = 0.002) and admission to ITU or HDU (p < 0.001) and longer postoperative admission of 3 (1-9) days for PAS0 vs 3 (2-12) for PAS1 vs 4.5 (3-6) for PAS2 vs 5 (3-22) for PAS3, p = 0.02. CONCLUSION: Perioperative complications are closely associated with PAS stage. This information is useful for counselling women and may be important in allocating staff and infrastructure resources at the time of delivery.

Managing the difficult case of fetal anemia.

OBJECTIVES: To describe a series of complex fetal anemia cases, detail the appropriate investigations and management, and review the literature. METHODS: Four cases of non-red cell alloimmunization or infective cases of fetal anemia are presented. RESULTS: Of the four cases presented, one was a neonatal death, one pregnancy was terminated, one case was diagnosed with Diamond Blackfan anemia, and one case was due to recurrent feto-maternal hemorrhages despite negative Kleihauer tests. CONCLUSIONS: Non-alloimmune causes of fetal anemia can be difficult to manage. Some cases require repeated and frequent intrauterine transfusions. The perinatal mortality and preterm delivery rates are increased, and some cases require considerable long-term treatment including regular transfusions. We present our experience of a series of non-immune fetal anemia managed in a tertiary unit, review the literature, and suggest appropriate management.