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Introduction: This review covers the recent literature on fetal brain magnetic resonance imaging, with emphasis on techniques, advances, common indications, and safety., Methods: We conducted a search of MEDLINE for articles published after 2010. The search terms used were "(fetal OR foetal OR fetus OR foetus) AND (MR OR MRI OR [magnetic resonance]) AND (brain OR cerebral)". Consensus statements from major authorities were also included. As a result, 44 relevant articles were included and formed the basis of this review., Results: One major challenge is fetal motion that is largely overcome by ultra-fast sequences. Currently, single-shot fast spin-echo T2-weighted imaging remains the mainstay for motion resistance and anatomical delineation. Recently, a snap-shot inversion recovery sequence has enabled robust T1-weighted images to be obtained, which is previously a challenge for standard gradient-echo acquisitions. Fetal diffusion-weighted imaging, diffusion tensor imaging, and magnetic resonance spectroscopy are also being developed. With multiplanar capabilities, superior contrast resolution and field of view, magnetic resonance imaging does not have the limitations of sonography, and can provide additional important information. Common indications include ventriculomegaly, callosum and posterior fossa abnormalities, and twin complications. There are safety concerns about magnetic resonance-induced heating and acoustic damage but current literature showed no conclusive evidence of deleterious fetal effects. The American College of Radiology guideline states that pregnant patients can be accepted to undergo magnetic resonance imaging at any stage of pregnancy if risk-benefit ratio to patients warrants that the study be performed., Conclusions: Magnetic resonance imaging of the fetal brain is a safe and powerful adjunct to sonography in prenatal diagnosis. It can provide additional information that aids clinical management, prognostication, and counselling.

Objective: To examine the applicability of hysterofetoscopy and cord blood collection at first trimester termination of pregnancy for fetal abnormalities., Methods: From 2004 to 2007, transcervical hysterofetoscopy was performed in seven patients at the same operation setting of surgical termination of pregnancy. The findings were compared with prenatal diagnosis. Feasibility of cord blood collection was also examined., Results: Out of these seven patients, six of them had prenatal ultrasound diagnosis of cystic hygroma. All of them had chromosomal abnormalities. Subcutaneous oedema was confirmed by hysterofetoscopy with good view. Another pregnancy was complicated by homozygous alpha thalassaemia and the diagnosis was confirmed by electrophoresis of fetal haemoglobin collected from umbilical cord vessel. Cord blood collection was also attempted in two other patients yielding fetal blood with minimal maternal contamination., Conclusion: Transcervical hysterofetoscopy is a feasible tool in confirming external fetal structural abnormalities before surgical termination of pregnancy. It can be performed under either general anaesthesia or conscious sedation. Umbilical cord blood collection can facilitate confirmation of genetic diseases. It may also allow the potential of isolating fetal mesenchymal stem cell in first trimester., (Copyright (c) 2008 John Wiley & Sons, Ltd.)

Objective: To explore whether the outcomes of second-trimester pregnancy termination for fetal abnormalities are affected by fetal diagnoses., Methods: This was a retrospective review of cases undergoing second-trimester pregnancy termination for the fetal diagnoses of hemoglobin Barts, trisomy 21, and trisomy 18 during the period from 1999 to 2006. The affected pregnancies were terminated by vaginal misoprostol. The outcome measures were: (1) abortion within 24 hours after misoprostol commencement, (2) histology-confirmed incomplete abortion, and (3) experience of significant side effects during termination (temperature over 39 degrees C or need for metoclopramide for vomiting)., Results: One hundred and twenty cases were available for analysis. After adjusting for maternal age, parity, history of cesarean delivery, body mass index, gestation, and fetal hydrops, pregnancy termination for trisomy 21 was associated with a higher risk of incomplete abortion than trisomy 18 and hemoglobin Barts (odds ratio 5.25, 95% confidence interval 1.24-22.19, p = 0.024). The chance of abortion within 24 hours and experience of significant side effects were not found to be associated with fetal diagnosis., Conclusions: Pregnancy termination for trisomy 21 is associated with a higher risk of incomplete abortion. Fetal diagnosis affects the outcome of pregnancy termination.

Objective: To test the hypothesis that the use of two-dimensional (2D) ultrasonography with three-dimensional/four-dimensional (3D/4D) ultrasonography can reduce anxiety to a greater extent in women at risk of having a fetus with congenital abnormalities than the use of 2D ultrasonography alone., Methods: A total of 124 women attending the prenatal diagnostic clinic of a teaching hospital were randomized into the intervention group (2D ultrasonography followed by 3D/4D ultrasonography) or control group (2D ultrasonography alone). The primary outcome was maternal anxiety levels, which were assessed by the Spielberger state-trait anxiety inventory. We measured the anxiety levels in all women at the first visit, at around 18 weeks' gestation (immediately after ultrasound examinations) and at 28 weeks' gestation., Results: A short-term reduction of the state-anxiety score (by around 2 points) from the first visit to after ultrasound examinations was observed in both the intervention group and the control group. Unexpectedly, a small increase in the state-anxiety score from the first visit to 28 weeks' gestation was observed in the intervention group but not in the control group, though there was no significant difference in the changes between the two groups. Repeated measures ANOVA (analysis of variance) also showed that there was no significant interaction effect between groups and time of assessment on the state-anxiety scores (F = 1.072 and P = 0.344). About 80% of women reported a better understanding that their baby was normal after viewing 3D rather than 2D images., Conclusion: This randomized study indicates that the addition of 3D/4D ultrasound does not cause a significant reduction in maternal anxiety in pregnancies at risk of fetal abnormalities compared with conventional 2D ultrasound alone., (Copyright 2006 ISUOG. Published by John Wiley & Sons, Ltd.)

Background: This prospective observational study aims at determining the distribution of fetal cerebro-placental Doppler indices and amniotic fluid volume in a homogenous group of uncomplicated postdated pregnancies at 41 weeks. The correlation with incidence of passage of thick meconium-stained liquor in labor was analyzed to decide which parameter would be useful in the surveillance of postdated pregnancies., Methods: The amniotic fluid volume, middle cerebral artery pulsatility index, umbilical artery pulsatility index, and cerebroplacental ratio were measured and distribution determined in 118 well-dated singleton pregnancies admitted for routine induction of labor at 41 weeks. The 10th centile and the 90th centile in each Doppler parameter and amniotic fluid volume were chosen to divide each parameter into three centile groups. The prevalence of thick meconium-stained liquor in labor in different Doppler and amniotic fluid volume centile groups was compared using Chi-square test for trend with P < 0.05 taken as statistically significant., Results: The prevalence of thick meconium-stained liquor in labor was significantly inversely correlated with the middle cerebral artery pulsatility index (P = 0.008), with significant difference across different middle cerebral artery pulsatility index centile groups (P = 0.02). There was no significant difference in the prevalence of thick meconium-stained liquor in labor or oligohydramnios across different umbilical artery pulsatility index centile groups. Neither was there significant difference in the prevalence of thick meconium-stained liquor in labor and oligohydramnios across different cerebroplacental ratio and amniotic fluid volume centile groups. Logistic regression using the 10th centile of middle cerebral artery pulsatility index confirmed that it was a significant independent predicting factor for risk of thick meconium-stained liquor in labor with adjusted odds ratio (95th CI) of 6.14 (1.6-24.1)., Conclusion: Middle cerebral artery pulsatility index is better than amniotic fluid volume or umbilical artery pulsatility index in predicting the risk of thick meconium-stained liquor in labor in uncomplicated postdated pregnancy at 41 weeks.

Objective: To describe Three-Dimensional eXtended Imaging (3DXI) as a new display modality for three-dimensional (3D) ultrasound examination of the fetus. Methods: The spine, palate, heart and brain were evaluated using 3D ultrasound examination at a mean gestational age of 22 weeks in 35, 31, 32 and 31 fetuses, respectively. The volume data captured were analyzed using the conventional orthogonal display mode (ODM), as well as the 3DXI, which includes the Multi-Slice View (MSV) mode and the Oblique View (OBV) mode. The MSV mode allows simultaneous display of multiple sequential parallel planes while the OBV mode allows examination of a non-standard straight or curved plane. Results: The MSV mode allowed a simultaneous display of multiple sequential parallel planes of the fetal structures, but we found some uncertainty if an isolated image in one of the multi-slice images represented the exact level of a fetal structure. The MSV mode was advantageous in one of the six cases of facial cleft by allowing the simultaneous display of bilateral clefts that were located in two different axial planes. The multi-slice images were helpful in making the diagnosis in one case of holoprosencephaly. The OBV mode allowed examination of the coronal plane across the curvature of the spine, and the 'in-plane' view of the interventricular septum in a non-gated study. Conclusion: The 3DXI can display the volume data in a different manner from that which usually results from the use of more conventional ODM, and provide additional information over conventional two-dimensional sonography. [ABSTRACT FROM AUTHOR]

Objective: To investigate the correlation between Doppler parameters in the umbilical and fetal middle cerebral arteries and pregnancy outcome in women with gestational diabetes mellitus (GDM). Methods: A prospective study was performed on 169 singleton GDM pregnancies in a university teaching hospital from January to December 2002. Umbilical artery (UA) pulsatility index (PI) and middle cerebral artery (MCA) PI and peak systolic velocity (Vmax) were measured every 4 weeks until delivery from the time of diagnosis of GDM. The pregnancy outcome was obtained from the hospital database. Using linear or quadratic regression, lines of best fit were drawn to compare the Doppler measurements between the two groups with normal and abnormal pregnancy outcomes. Results: One hundred and thirty-eight women with known pregnancy outcome completed the study. A total of 305 Doppler examinations were performed with one to four examinations for each woman. Thirty-eight women (27.5%) had one or more abnormal pregnancy outcomes: placental abruption, pre-eclampsia, preterm delivery, small-for-gestational age (SGA) infants, low Apgar scores, neonatal jaundice requiring treatment, sepsis, birth trauma, meconium aspiration syndrome, respiratory and neurological complications. There was extensive overlap of the UA-PI, MCA-PI and MCA-Vmax measurements between the two groups. Conclusion: A Doppler study of the UA-PI, MCA-PI and MCA-Vmax was not useful in the prediction of abnormal pregnancy outcome in GDM. [ABSTRACT FROM AUTHOR]