Inga Sandaite

Technical aspects of fetal endoscopic tracheal occlusion for congenital diaphragmatic hernia

In isolated congenital diaphragmatic hernia, prenatal prediction is made based on measurements of lung size and the presence of liver herniation into the thorax. A subset of fetuses likely to die in the postnatal period is eligible for fetal intervention that can promote lung growth. Rather than anatomical repair, this is now attempted by temporary fetal endoscopic tracheal occlusion (FETO). Herein we describe purpose-designed instruments that were developed thanks to a grant from the European Commission. The feasibility and safety of FETO have now been demonstrated in several active fetal surgery programs. The most frequent complication of the procedure is preterm premature rupture of the membranes, which is probably iatrogenic in nature. It does have an impact on gestational age at delivery and complicates balloon removal. FETO is associated with an apparent increase in survival compared with same severity controls, although this needs to be evaluated in a formal trial. The time has come to do so.

The correlation between lung volume and liver herniation measurements by fetal MRI in isolated congenital diaphragmatic hernia: a systematic review and meta‐analysis of observational studies

We conducted a meta‐analysis to assess the correlation of lung volume and liver position measured by magnetic resonance imaging (MRI) with survival until discharge in fetuses with isolated congenital diaphragmatic hernia (CDH).

Prenatal Anatomical Imaging in Fetuses with Congenital Diaphragmatic Hernia

The role of prenatal ultrasound and magnetic resonance imaging in the diagnosis and management of congenital diaphragmatic hernia (CDH) is reviewed. Topics include morphologic imaging and vascular assessment of the developing lung, the value of imaging parameters as prognostic predictors in CDH and the role of imaging following percutaneous fetoscopic endoluminal tracheal occlusion.

Fetal surgery is a clinical reality

An increasing number of fetal anomalies are being diagnosed prior to birth, some of them amenable to fetal surgical intervention. We discuss the current clinical status and recent advances in endoscopic and open surgical interventions. In Europe, fetoscopic interventions are widely embraced, whereas the uptake of open fetal surgery is much less. The indications for each access modality are different, hence they cannot substitute each other. Although the stage of technical experimentation is over, most interventions remain investigational. Today there is level I evidence that fetoscopic laser surgery for twin-to-twin transfusion syndrome is the preferred therapy, but this operation actually takes place on the placenta. In terms of surgery on the fetus, an increasingly frequent indication is severe congenital diaphragmatic hernia as well as myelomeningocele. Overall maternal safety is high, but rupture of the membranes and preterm delivery remain a problem. The increasing application of fetal surgery and its mediagenicity has triggered the interest to embark on fetal surgical therapy, although the complexity as well as the overall rare indications are a limitation to sufficient experience on an individual basis. We plead for increased exchange between high volume units and collaborative studies; there may also be a case for self-regulation. Inclusion of patients into trials whenever possible should be encouraged rather than building up casuistic experience.

Examining the Relationship between the Lung-to-Head Ratio Measured on Ultrasound and Lung Volumetry by Magnetic Resonance in Fetuses with Isolated Congenital Diaphragmatic Hernia

Purpose: In fetuses with isolated congenital diaphragmatic hernia (CDH), lung development can be measured by the lung-to-head ratio (LHR) using ultrasound as well as by lung volumetry determined by fetal magnetic resonance imaging (MRI). We aimed to investigate their relationship as well as to analyze the factors that may have an impact on it. Material and Methods: In 153 consecutive fetuses with isolated CDH, both the LHR and total fetal lung volume (TFLV) were measured. The observed LHR was calculated by dividing the lung area by the head circumference. On MRI, planimetric measurements of ipsilateral, contralateral and TFLV were performed on T2-HASTE (half-Fourier acquisition single-shot turbo spin echo) sequences in transverse as well as coronal or sagittal planes. All values were expressed as a ratio of what was observed over what is expected in a gestational age-matched normal fetus. Secondary analyses were performed for right- versus left-sided hernia and for measurements made prior to 25 weeks’ gestation. A multivariate linear regression approach was used to determine the influence of the independent variables such as observed/expected (O/E) LHR, gestational age, liver position and CDH side on the dependent variables O/E TFLV and O/E contralateral FLV, and to determine the optimal formulas for calculation of the O/E TFLV as well as contralateral FLV. Results: In total, 200 pairs of measurements were obtained between 20 and 37 weeks’ gestation (median 26+6). There was a significant association between the O/E contralateral FLV and O/E LHR (R2 = 0.44; p < 0.001) as well as between the O/E TFLV and the O/E LHR (R2 = 0.37; p < 0.001). After adding the independent variables that were first shown to be significant on univariate analysis, the multiple regression analysis demonstrated that gestational age (p = 0.017) and side of the defect (p < 0.001) were predictive of O/E LHR (p < 0.001) and strongly improved the estimation of O/E TFLV (R2 = 0.43 instead of 0.37 when using O/E LHR only). In terms of estimating O/E contralateral FLV, only the O/E LHR was a significant (p < 0.001) independent predictor (R2 = 0.44). These correlations also applied when considering only left-sided CDH cases. For measurements done prior to the third trimester, the O/E LHR (p = 0.034), gestational age (p = 0.035) as well as liver herniation (p = 0.029) were significantly correlated to the O/E TFLV (R2 = 0.33). In terms of predicting the O/E contralateral FLV (R2 = 0.25), only O/E LHR (p = 0.008) and gestational age (p = 0.037) were useful predictors. Conclusion: Measurement of the O/E LHR on ultrasound allows a good estimation of the O/E contralateral FLV as well as TFLV as measured by MRI. Whereas the additional parameters such as gestational age, liver position and side of the defect did not improve the estimation of the contralateral FLV, they did so for estimating the TFLV.

Right‐sided congenital diaphragmatic hernia in a decade of fetal surgery

To report a recent update on fetuses with right‐sided congenital diaphragmatic hernia (RCDH) in the era of fetal surgery.

A morphometric study of the human fetal heart on post-mortem 3-tesla magnetic resonance imaging

To report on the feasibility of assessing cardiac structures on post‐mortem 3‐tesla MRI (pmMRI) and to provide morphometric data in fetuses without cardiac abnormalities.

Outcome of fetuses with congenital diaphragmatic hernia and associated intrafetal fluid effusions managed in the era of fetal surgery.

Fetuses with congenital diaphragmatic hernia (CDH) and for whom additional ultrasound findings are abnormal typically are considered to have a dismal prognosis. Our aim was to assess the outcome of fetuses with CDH and associated intrafetal fluid effusions.

The use of endoscopy in fetal medicine

We aimed to review the state of affairs in the field of embryo–fetoscopy as well as its instrumental requirements. Today, endoscopic procedures of limited complexity are easily possible within the amniotic cavity. Embryoscopy is typically done for diagnostic purposes, such as the demonstration of external anomalies very early in pregnancy and/or obtaining embryonic tissues in recurrent miscarriages. Fetoscopy is the direct visualization of the amniotic cavity from the second trimester onwards. Its principal indications are complications of monochorionic twinning and severe congenital diaphragmatic hernia. There is level I evidence that fetoscopic laser surgery for twin–twin-transfusion syndrome is superior over amniodrainage. Fetoscopic endoluminal tracheal occlusion is done for severe diaphragmatic hernia. Whether tracheal occlusion yields better outcomes than expectant management during pregnancies is currently being investigated in a randomized trial. There are a number of less common procedures discussed as well. Overall, maternal risks of embryo–fetoscopy are minimal. The most frequent complication is rupture of the membranes and as a consequence preterm delivery. Fetal surgery seems safe and has, therefore, become a clinical reality. Although the stage of technical experimentation is over, most interventions remain investigational. Inclusion of patients into trials whenever possible should be encouraged, rather than building up casuistic experience.

Comparison of matching by body volume or gestational age for calculation of observed to expected total lung volume in fetuses with isolated congenital diaphragmatic hernia

To determine the bias induced by matching fetuses according to gestational age (GA) or fetal body volume (FBV) when calculating the observed to expected total fetal lung volume (o/e TFLV) in cases of isolated congenital diaphragmatic hernia (CDH).