Correlation of observed-to-expected total fetal lung volume with intrathoracic organ herniation on magnetic resonance imaging in fetuses with isolated left-sided congenital diaphragmatic hernia

Risk Stratification by Percent Liver Herniation in Congenital Diaphragmatic Hernia

INTRODUCTION

Congenital diaphragmatic hernia is associated with pulmonary hypoplasia, pulmonary hypertension, and significant neonatal morbidity. Although intrathoracic liver herniation (LH) >20% is associated with adverse outcomes, the relationship between LH <20% and outcomes is poorly characterized.

METHODS

A single-center retrospective cohort study was performed from 2011 to 2020 of 80 fetuses with left-sided congenital diaphragmatic hernia that were delivered and repaired at our institution. Perinatal, perioperative, and postoperative data were collected. We evaluated the association of %LH with outcomes as a stratified ordinal variable (0%-10% LH, 10%-19% LH, and >20% LH) and as a continuous variable. Data were analyzed by analysis of variance with Bonferroni post hoc analysis, chi-square analyses, and univariate logistic regression.

RESULTS

Extracorporeal membrane oxygenation (ECMO) (P < 0.001), repair on ECMO (P = 0.002), repair with patch (P < 0.001), length of stay (P = 0.002), inhaled nitric oxide use (P < 0.001), and sildenafil use at discharge (P < 0.001), showed significant differences among LH groups. There were no differences among the groups concerning survival (at discharge, 6 mo, and 1 y) and tracheostomy. On further analysis there was no difference between 10% and 19% LH and ≥20% LH patients concerning ECMO (P = 0.55), repair on ECMO (P = 0.54), repair with patch (P = 1.00), length of stay (P = 1.00), and inhaled nitric oxide use (P = 0.33). Logistic regression analysis displayed a significant association with LH and ECMO, repair on ECMO, repair with patch, inhaled nitric oxide use, and sildenafil use.

CONCLUSIONS

Our analysis displays no significant difference in perinatal management between patients with 10%-19% and ≥20% LH. These findings suggest that the historical cutoff of ≥20% LH may not be sufficient alone to guide perinatal counseling and decision-making.

Antenatal Management of Congenital Diaphragmatic Hernia: what's next ?

Congenital diaphragmatic hernia (CDH) can be diagnosed in the prenatal period and its severity can be measured by fetal imaging. There is now level I evidence that, in selected cases, Fetoscopic Endoluminal Tracheal Occlusion (FETO) increases survival to discharge from the neonatal unit as well as the risk for prematurity. Both effects are dependent on the time point of tracheal occlusion. FETO may also lead to iatrogenic death when done in unexperienced centres. The implementation of the findings from our clinical studies, may also vary based on local conditions. These may be different in terms of available skill set, access to fetal therapy, as well as outcome based on local neonatal management. We encourage prior benchmarking of local outcomes with optimal postnatal management, based on large enough numbers and using identical criteria as in the recent trials. We propose to work further on prenatal prediction methods, and the improvement of fetal intervention. In this manuscript, we describe a research agenda from a fetal medicine perspective. This research should be in parallel with innovation in neonatal and pediatric (surgical) management of this condition. This article is protected by copyright. All rights reserved.

The role of magnetic resonance imaging in the diagnosis and prognostic evaluation of fetuses with congenital diaphragmatic hernia

In recent years, magnetic resonance imaging (MRI) has largely increased our knowledge and predictive accuracy of congenital diaphragmatic hernia (CDH) in the fetus. Thanks to its technical advantages, better anatomical definition, and superiority in fetal lung volume estimation, fetal MRI has been demonstrated to be superior to 2D and 3D ultrasound alone in CDH diagnosis and outcome prediction. This is of crucial importance for prenatal counseling, risk stratification, and decision-making approach. Furthermore, several quantitative and qualitative parameters can be evaluated simultaneously, which have been associated with survival, postnatal course severity, and long-term morbidity.

CONCLUSION

Fetal MRI will further strengthen its role in the near future, but it is necessary to reach a consensus on indications, methodology, and data interpretation. In addition, it is required data integration from different imaging modalities and clinical courses, especially for predicting postnatal pulmonary hypertension. This would lead to a comprehensive prognostic assessment.

WHAT IS KNOWN

• MRI plays a key role in evaluating the fetal lung in patients with CDH. • Prognostic assessment of CDH is challenging, and advanced imaging is crucial for a complete prenatal assessment and counseling.

WHAT IS NEW

• Fetal MRI has strengthened its role over ultrasound due to its technical advantages, better anatomical definition, superior fetal lung volume estimation, and outcome prediction. • Imaging and clinical data integration is the most desirable strategy and may provide new MRI applications and future research opportunities.

Magnetic Resonance Prediction of Lung Maturity in Fetuses With Congenital Diaphragmatic Hernia

ABSTRACT

To determine if lung to liver MR T2 signal ratio is predictive of neonatal outcome in fetuses with congenital diaphragmatic hernia (CDH).After Interal Review Board approval, the PACS systems at the University of Washington and University of Utah were searched for cases having an in utero fetal MR examination diagnostic of CDH. Inclusion criteria were at least 1 prior ultrasound demonstrating a CDH and an MR obtained within 1 week of that prior ultrasound.A total of 69 patients from the University of Utah and 13 from the University of Washington satisfied the inclusion criteria for a total of 82. After adjusting for gestational age and contralateral lung volume, there was little apparent association between contralateral lung to liver MR T2 signal and 5-minute Apgar score and neonatal mortality When considering neonatal Apgar and mortality, increasing contralateral lung volume was significantly associated with lower risk (hazard ratio, 0.40 per doubling; 95% confidence interval, 0.24-0.69; P = 0.001) as expected.Our data demonstrate that the lung to liver MR signal ratio was not predictive of outcome. The measurement of contralateral lung area, and gestational age at the time of the examination (time of diagnosis) are still the best predictors of poor neonatal outcome.

Prenatal evaluation of functional pulmonary hypoplasia via fetal magnetic resonance imaging

OBJECTIVE

The purpose of this study was to retrospectively examine the use of lung-to-liver signal intensity ratio (LLSIR) on T2-weighted images to predict functional pulmonary hypoplasia.

METHODS

The subjects of this study were pregnant women who underwent magnetic resonance imaging (MRI). Patients who required nitric oxide inhalation and those who died from respiratory disorders were classified as having functional pulmonary hypoplasia (FPH). All other cases were presented as the control group. We retrospectively analyzed MRI and perinatal data. LLSIR was defined as the ratio of lung signal intensity to liver signal intensity. We examined the relationship between LLSIR and gestational age, compared the LLSIRs in the two groups, and calculated the best cut-off value of the LLSIR to predict FPH.

RESULTS

One hundred and ninety-one patients were eligible for this study, and 12 cases were classified as having FPH. In the control group, LLSIR increased with age (r = 0.383, p < 0.001). We used the observed/expected LLSIR (o/e LLSIR), which was the ratio of obtained LLSIR to expected LLSIR calculated by the regression line to correct the effect of gestational age. In the FHP group, o/e LLSIR was significantly lower than in the control group (p < 0.001). A receiver operating characteristic curve analysis showed that cases with o/e LLSIR above 0.85 were less likely to cause FPH.

CONCLUSIONS

Low o/e LLSIR might reflect the histological characteristics of hypoplastic lung structures. O/e LLSIR seems to be a useful MRI parameter for screening FPH.

Fetal body MRI and its application to fetal and neonatal treatment: an illustrative review

This Review depicts the evolving role of MRI in the diagnosis and prognostication of anomalies of the fetal body, here including head and neck, thorax, abdomen and spine. A review of the current literature on the latest developments in antenatal imaging for diagnosis and prognostication of congenital anomalies is coupled with illustrative cases in true radiological planes with viewable three-dimensional video models that show the potential of post-acquisition reconstruction protocols. We discuss the benefits and limitations of fetal MRI, from anomaly detection, to classification and prognostication, and defines the role of imaging in the decision to proceed to fetal intervention, across the breadth of included conditions. We also consider the current capabilities of ultrasound and explore how MRI and ultrasound can complement each other in the future of fetal imaging.

What should we tell parents? Congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is characterized by a defect in the muscle dividing the thoracic and abdominal cavities. This leads to herniation of the abdominal organs into the thorax and a disturbance of lung development. Two-thirds of cases are identified by prenatal ultrasound in the second trimester, which should prompt referral to a tertiary center for prognosis assessment and counseling by a multidisciplinary team familiar with this condition. In this review, we summarize evidence on prenatal diagnosis and postnatal management of CDH. There is a focus on information that should be provided to expecting parents during prenatal counseling.

Fetal MRI assessment of mediastinal shift angle in isolated left congenital diaphragmatic hernia: A new postnatal survival predictive tool?

OBJECTIVE

To quantify the mediastinal shift angle (MSA) in fetuses with isolated left congenital diaphragmatic hernia (CDH) by magnetic resonance imaging and evaluate survival.

METHOD

Fetuses from singleton pregnancies with isolated left CDH were matched for gestational age with controls without thoracic malformations. For all fetuses the MSA was determined by two operators and inter-operator variability and differences between cases and controls were investigated. For all cases total fetal lung volume (TFLV) was calculated and the correlation between MSA and TFLV was assessed, and its predictive value towards survival was determined.

RESULTS

Thirty-four fetuses were included as cases and 42 as controls. The mean gestational age for assessment of CDH fetuses was 32 weeks (range 27-38). Twenty-four fetuses survived until discharge and 10 did not. There was an excellent inter-operator reliability for measuring the MSA and a significant difference between MSA in cases and controls. There was an inverse correlation between MSA values and survival, a correlation between TFLV and survival and an inverse correlation between MSA and TFLV. The area under the ROC curve for MSA in predicting survival was 0.931 (95% CI 0.851-1.000).

CONCLUSION

The MSA measured late in gestation correlates with postnatal survival in patients with isolated left CDH.

Prenatal Imaging Features and Postnatal Factors Associated with Gastrointestinal Morbidity in Congenital Diaphragmatic Hernia

BACKGROUND

To perform a comprehensive assessment of postnatal gastrointestinal (GI) morbidity and determine the prenatal imaging features and postnatal factors associated with its development in patients with congenital diaphragmatic hernia (CDH).

MATERIALS AND METHODS

A retrospective review was conducted of all infants evaluated for CDH at a quaternary fetal center from February 2004 to May 2017. Prenatal imaging features and postnatal variables were analyzed. GI morbidity was the primary outcome. The Mann-Whitney U test, the Kruskal-Wallis test with Dunnett's T3 post hoc analysis and logistic regression, and the χ2 test were performed when appropriate.

RESULTS

We evaluated 256 infants; 191 (75%) underwent CDH repair and had at least 6 months of follow-up. Of this cohort, 60% had gastroesophageal reflux disease (GERD), 13% had gastroparesis, 32% received a gastrostomy tube (G-tube), and 17% needed a fundoplication. Large defect, patch repair, extracorporeal membrane oxygenation (ECMO), and prolonged use of mechanical ventilation were significantly associated with having GERD, gastroparesis, G-tube placement, and fundoplication (p < 0.05). Fetuses with stomach grades 3 and 4 were most likely to have GERD, a G-tube, and a long-term need for supplemental nutrition than fetuses with stomach grades 1 and 2 (p < 0.05).

CONCLUSION

Survivors of CDH with large defects, prolonged use of mechanical ventilation, or that have received ECMO may be at an increased risk for having GERD, gastroparesis, and major GI surgery. Marked stomach displacement on prenatal imaging is significantly associated with GI morbidity in left-sided CDH.

Prenatal diagnosis and management of congenital diaphragmatic hernia

Congenital diaphragmatic hernia is characterized by failed closure of the diaphragm, thereby allowing abdominal viscera to herniate into the thoracic cavity and subsequently interfering with normal lung development. At birth, pulmonary hypoplasia leads to respiratory insufficiency and persistent pulmonary hypertension (PHT), that is lethal in up to 32% of patients. In isolated cases, the outcome may be predicted prenatally by medical imaging and advanced genetic testing. In those fetuses with a predicted poor outcome, fetoscopic endoluminal tracheal occlusion may be offered. This procedure is currently being evaluated in a global randomized clinical trial (www.TOTALtrial.eu). We are currently investigating alternative strategies including transplacental sildenafil administration to reduce the occurrence of persistent PHT.

Ultrasonographic assessment of mediastinal shift angle (MSA) in isolated left congenital diaphragmatic hernia for the prediction of postnatal survival

Objectives: To quantify mediastinal shift in isolated congenital diaphragmatic hernia (CDH), by the introduction of a new ultrasonographic (US) marker, defined as mediastinal shift angle (MSA) and to evaluate its ability in predicting postnatal survival at discharge.Methods: Twenty-four consecutive fetuses from singleton pregnancies with isolated left-sided CDH were included in the study group and then subdivided into group A (16 survivors) and group B (8 nonsurvivors). The study group was matched with a control group of 95 fetuses from singleton pregnancies free from structural and/or chromosomal anomalies. On the same US stored images commonly used for lung-to-head ratio (LHR) measurement, a landmark line was drawn from a point on the posterior face of the vertebral body, splitting it into two equal parts, to the mid-posterior surface of the sternum. Another landmark line was then traced from the same point of the vertebral body to touch tangentially the lateral wall of the right atrium. The angle between these two lines was used to quantify mediastinal shift and called "mediastinal shift angle" (MSA).Results: Median MSA was significantly different between group A (34.3° range 29.3-45.9°) and group B (42.7° range 34.1-58.9°) (p < .001) and between study group as a whole and the control group (19° range 13.8-25.9°) (p < .001). Statistical analysis confirmed an inverse correlation between MSA values and survival (p = .004). The best cutoff value for MSA was 43.7°, which demonstrated the highest discriminatory power (sensitivity 63%; specificity 93.75%).Conclusions: In fetuses with isolated CDH, the mediastinal shift may be quantified using mediastinal shift angle (MSA) and this US marker, similarly to the widely accepted and used US prenatal prognostic indicators (LHR and O/E LHR), seems to reliably predict survival.

Pre- and neonatal imaging of gastrointestinal complications in congenital diaphragmatic hernia

The initial outcome in infants with congenital diaphragmatic hernia is mainly related to the associated lung hypoplasia. However, these patients frequently present with additional gastrointestinal pathology that also influences their quality of life and final prognosis. Congenital gastrointestinal anomalies are often observed and the displacement of the liver, the stomach and/or the intestines into the thorax may cause distortion of the vascular axis of these organs, increasing the risk of congestion and/or ischemia. Some of these gastrointestinal complications are already visible at imaging studies performed in utero and/or in newborns.This pictorial essay describes the imaging findings of the most frequently detected gastrointestinal complications in fetuses and infants with congenital diaphragmatic hernia, focusing on prenatal exams.

Lung and liver growth and retinoic acid status in human fetuses with congenital diaphragmatic hernia

BACKGROUND

Abnormal retinoic acid (RA) signalling is considered a major cause of congenital diaphragmatic hernia (CDH). Pulmonary hypoplasia and pulmonary hypertension are the major causes of morbidity and mortality in infants born with CDH. Experimental studies in animals have found that RA signalling is involved in lung and liver development, but animal models of CDH do not directly correlate with CDH in human fetuses. This study investigated if RA status is also linked to lung and liver growth in human fetuses with CDH.

STUDY DESIGN AND PATIENTS

Hepatic stellate cells (HSC) in autopsy human fetal liver tissue were identified using cRBP-1 immunohistochemistry and the numbers of HSC manually counted. In mammals, RA is principally stored in HSC complexed to cRBP-1 and therefore cRBP-1⁺ HSC numbers were used as an indicator of fetal RA status. The number of HSCs was correlated with liver and lung weights, calculated relative to either normal biometric values or fetal body weight.

RESULTS

The number of cRBP-1⁺ HSCs correlated with lung weight contralateral to the side of the diaphragmatic hernia (r=0.82, p=0.025) and combined lung weight (r=0.78, p=0.039) but not with ipsilateral lung weight (r=0.43, p=0.33), in fetuses with right and left CDH and a case of giant omphalocoele. Liver growth was influenced by contact with diaphragm but not significantly correlated with cRBP-1 expression (r=0.52, p=0.056).

CONCLUSION

Fetal RA stores, reflected in the number of cRBP-1⁺ HSCs, influence lung growth as well as diaphragm development in human fetuses with CDH. Contact with diaphragm influenced liver growth.

Current and future antenatal management of isolated congenital diaphragmatic hernia

Congenital diaphragmatic hernia is surgically correctable, yet the poor lung development determines mortality and morbidity. In isolated cases the outcome may be predicted prenatally by medical imaging. Cases with a poor prognosis could be treated before birth. However, prenatal modulation of lung development remains experimental. Fetoscopic endoluminal tracheal occlusion triggers lung growth and is currently being evaluated in a global clinical trial. Prenatal transplacental sildenafil administration may in due course be a therapeutic approach, reducing the occurrence of persistent pulmonary hypertension, either alone or in combination with fetal surgery.