Value of prenatal magnetic resonance imaging in the prediction of postnatal outcome in fetuses with diaphragmatic hernia

OBJECTIVES

To investigate the potential value of antenatally determined total fetal lung volume (TFLV) by magnetic resonance imaging (MRI) in the prediction of the postnatal survival in congenital diaphragmatic hernia (CDH).

METHODS

We examined fetuses with isolated CDH, in which MRI was used at 22-38 weeks of gestation to measure TFLV and assess intrathoracic herniation of abdominal viscera, that were liveborn after 30 weeks of gestation and had postnatal follow-up until death or discharge from hospital. Regression analysis was used to investigate the effect on survival of gestational age at diagnosis, observed to expected (o/e) TFLV, intrathoracic herniation of the liver, side of CDH, gestational age at MRI, institution, year and gestational age at delivery. In 76 fetuses measurements of o/e TFLV and the lung area to head circumference ratio (LHR) were performed within 2 weeks of each other; in these cases o/e TFLV and o/e LHR were compared for their prediction of postnatal survival.

RESULTS

In the 148 cases that fulfilled the entry criteria, multiple regression analysis demonstrated that significant predictors of survival were the presence or absence of intrathoracic herniation of the liver and o/e TFLV. The area under the receiver-operating characteristics curves for prediction of postnatal survival from o/e TFLV was 0.786 (standard error, 0.059; P < 0.001) and that from o/e LHR was 0.743 (standard error, 0.069; P = 0.001).

CONCLUSIONS

In the assessment of fetuses with CDH, MRI-based o/e TFLV is useful in the prediction of postnatal survival.

[Antenatal prediction of pulmonary hypoplasia and intrauterine treatment by endoscopic fetal tracheal occlusion in severe isolated congenital diaphragmatic hernia]

Congenital diaphragmatic hernia (CDH) affects one in 2500 to 5000 births and can be detected in utero by means of ultrasound screening Associated structural problems aggravate the prognosis. The survival rate is 70% or more for cases managed in tertiary care centers. The commonest causes of neonatal death in this setting are pulmonary hypoplasia and pulmonary hypertension. Prenatal imaging findings can now accurately predict postnatal outcome, based mainly on ultrasound determination of the lung-to-head ratio and liver position. This information can be used to counsel patients. In severe cases, prenatal intervention can reverse pulmonary hypoplasia. We review current data on prenatal prediction of neonatal survival. We also discuss experimental and clinical data on the benefits of fetal tracheal occlusion. The TOTAL trial (Tracheal Occlusion To Accelerate Lung growth) is currently ongoing in Europe.

[MRI and fetal multidetector CT in the diagnosis of fetal malformations]

Prenatal imaging has benefitted from rapid technological progress in the last ten years. Ultrasound remains the standard screening method for fetal malformations but can be hindered by the bony structure of the skull. In particular, it can be difficult to distinguish between white and grey matter. MRI is a useful complementary method for detecting brain malformations. In particular, MRI is necessary to detect associated malformations and to obtain a precise diagnosis when ultrasound examination shows ventricular dilation. MRI is taking an increasingly important place in the assessment and prognostication of extracranial malformations such as congenital diaphagmatic hernia. We reviewed 2885 fetal MRI examinations. Fetal computed tomography is gradually replacing plain maternal abdominal radiography. We examined 90 CT films for fetal bone malformations.

Matrix metalloproteinase gene polymorphisms and bronchopulmonary dysplasia: identification of MMP16 as a new player in lung development

BACKGROUND

Alveolarization requires coordinated extracellular matrix remodeling, a process in which matrix metalloproteinases (MMPs) play an important role. We postulated that polymorphisms in MMP genes might affect MMP function in preterm lungs and thus influence the risk of bronchopulmonary dysplasia (BPD).

METHODS AND FINDINGS

Two hundred and eighty-four consecutive neonates with a gestational age of <28 weeks were included in this prospective study. Forty-five neonates developed BPD. Nine single-nucleotide polymorphisms (SNPs) were sought in the MMP2, MMP14 and MMP16 genes. After adjustment for birth weight and ethnic origin, the TT genotype of MMP16 C/T (rs2664352) and the GG genotype of MMP16 A/G (rs2664349) were found to protect from BPD. These genotypes were also associated with a smaller active fraction of MMP2 and with a 3-fold-lower MMP16 protein level in tracheal aspirates collected within 3 days after birth. Further evaluation of MMP16 expression during the course of normal human and rat lung development showed relatively low expression during the canalicular and saccular stages and a clear increase in both mRNA and protein levels during the alveolar stage. In two newborn rat models of arrested alveolarization the lung MMP16 mRNA level was less than 50% of normal.

CONCLUSIONS

MMP16 may be involved in the development of lung alveoli. MMP16 polymorphisms appear to influence not only the pulmonary expression and function of MMP16 but also the risk of BPD in premature infants.

Three-dimensional sonographic measurement of contralateral lung volume in fetuses with isolated congenital diaphragmatic hernia

PURPOSE

To use 3-dimensional sonography (3DUS) to measure contralateral lung volume and evaluate the potential of this measurement to predict neonatal outcome in isolated congenital diaphragmatic hernia (CDH).

METHODS

Between January 2002 and December 2004, the contralateral lung volumes of 39 fetuses with isolated CDH were measured via 3DUS using rotational multiplanar imaging. The observed/expected contralateral fetal lung volume ratios (o/e-ContFLVR) were compared with the lung/head ratio (LHR), observed/expected total fetal lung volume ratio (o/e-TotFLVR), and postnatal outcome.

RESULTS

Contralateral lung volumes are less reduced than total lung volumes in CDH. The bias and precision of 3DUS in estimating contralateral lung volumes were 0.99 cm(3) and 1.11 cm(3), respectively, with absolute limits of agreement ranging from -1.19 cm(3) to +3.17 cm(3). The o/e-ContFLVR was significantly lower in neonatal death cases (median, 0.49 cm(3); range, 0.22-0.99 cm(3)) than in survival cases (median, 0.58 cm(3); range, 0.42-0.92 cm(3) [p < 0.01]). Overall accuracy of the o/e-ContFLVR, o/e-TotFLVR, and LHR in predicting neonatal death were 67.7% (21/31), 80.7% (25/31), and 77.4% (24/31), respectively.

CONCLUSION

Although o/e-ContFLVR can be precisely measured with 3DUS and can be used to predict neonatal death in CDH, it is less accurate than LHR and o/e-TotFLVR for that purpose.

Predicting perinatal outcome in isolated congenital diaphragmatic hernia using fetal pulmonary artery diameters

OBJECTIVE

The aim of the study was to evaluate the potential of fetal pulmonary artery (PA) diameters to predict perinatal death and pulmonary arterial hypertension (PAH) in congenital diaphragmatic hernia (CDH).

STUDY DESIGN

In this prospective observational study, observed PA (main, right, and left) diameters were measured at the level of the 3 vessels in 21 fetuses with isolated CDH and in 85 controls at 22 to 36 weeks. The observed/expected (o/e) diameters of the main, contralateral, and ipsilateral PAs were calculated by comparing these measurements with reference values obtained in our previous study and correlated with perinatal death and postnatal PAH.

RESULTS

The o/e PA diameters were significantly reduced in fetuses with CDH compared to controls (P < .001) and in fetuses with CDH who died (P < .050). However, there was no significant association between PA diameters and PAH (P >or= .050).

CONCLUSIONS

The PA diameters might be useful to predict perinatal death in isolated CDH but not postnatal PAH, suggesting that PA diameters are probably related to the severity of pulmonary hypoplasia.

Experience in the Management of Eighty-Two Newborns With Congenital Diaphragmatic Hernia Treated With High-Frequency Oscillatory Ventilation and Delayed Surgery Without the Use of Extracorporeal Membrane Oxygenation

The aim of this study is to analyze neonatal outcome of isolated congenital diaphragmatic hernia and to identify prenatal and postnatal prognosis-related factors. A retrospective single institution series from January 2000 to November 2005 of isolated congenital diaphragmatic hernia neonates was reviewed. Respiratory-care strategy was early high-frequency oscillatory ventilation, nitric oxide in pulmonary hypertension, and delayed surgery after respiratory and hemodynamic stabilization. Survival rate at 1 month was 65.9%. None of the prenatal factors were predictive of neonatal outcome, except an intra-abdominal stomach in left diaphragmatic hernia. Preoperative pulmonary hypertension was more severe in the nonsurvivor group and was predictive of length of ventilation in the survivors. During the first 48 hours of life, the best oxygenation index above 13 and the best PaCO2 above 45 were predictive of poor outcome. When treating isolated congenital diaphragmatic hernia with early high-frequency ventilation and delayed surgery but excluding extracorporeal membrane oxygenation, survival rates compare favorably with other reported series, and the respiratory morbidity is low.

Timing of lung size assessment in the prediction of survival in fetuses with diaphragmatic hernia

OBJECTIVES

To investigate whether the prediction of postnatal outcome of fetuses with isolated congenital diaphragmatic hernia depends on the gestational age at assessment using the fetal observed to expected (O/E) lung area to head circumference ratio (LHR), by comparing the performance of the test at 22-23 weeks with that at 32-33 weeks of gestation.

METHODS

Following prenatal diagnosis of isolated diaphragmatic hernia before 22 weeks, we evaluated the O/E LHR at 22-32 weeks and again at 32-33 weeks of gestation. Only cases liveborn beyond 34 weeks of gestation and with postnatal follow-up available until discharge from the hospital were included. Regression analysis was used to examine the effect on postnatal survival of O/E LHR, gestational age at delivery, side of the diaphragmatic hernia and intrathoracic position of the liver. Wilcoxon rank test for paired samples was used to compare median O/E LHR at 22-23 weeks and 32-33 weeks, in babies who survived and in those who died. Receiver-operating characteristics (ROC) curves were constructed for the prediction of survival by O/E LHR at 22-23 weeks and at 32-33 weeks.

RESULTS

In total, 53 pairs of measurements could be assessed. Univariate logistic regression analysis demonstrated that significant predictors of survival were the presence or absence of intrathoracic herniation of the liver, the O/E LHR at 22-23 weeks and the O/E LHR at 32-33 weeks of gestation. Multivariate logistic regression analysis demonstrated that only O/E LHR at 22-23 weeks or 32-33 weeks provided significant independent prediction of survival. The median O/E LHR at 22-23 weeks was not significantly different from that at 32-23 weeks either in survivors or in babies that subsequently died in the neonatal period (P = 0.25 and P = 0.09, respectively). The area under the ROC curve for prediction of postnatal survival from the O/E LHR at 22-23 weeks was 0.789 (P < 0.001) and that for prediction from the O/E LHR at 32-33 weeks was 0.842 (P < 0.001).

CONCLUSIONS

In isolated diaphragmatic hernia, O/E LHR measurement at 22-23 weeks as well as at 32-33 weeks provides useful independent prediction of subsequent survival. The prediction of postnatal survival using O/E LHR is independent of the timing of assessment.

Prenatal prognosis in isolated congenital diaphragmatic hernia

OBJECTIVE

A monocentric retrospective study of 79 neonates with isolated diaphragmatic hernia antenatally diagnosed was performed to identify prenatal parameters that may characterize the severity of the disease.

STUDY DESIGN

Postnatal treatment protocol included early high frequency ventilation, inhaled nitric oxide, and delayed surgery. Postnatal survival rate was 63.3%.

RESULTS

Age at diagnosis, polyhydramnios, and left ventricle/right ventricle index were not related with survival. None of the 9 left diaphragmatic hernias with intraabdominal stomach died. Neonatal mortality was significantly related with the side of the defect, intrathoracic position of the liver, the ratio of fetal lung area to head circumference value, and fetal lung volume ratio measured by resonance magnetic imaging.

CONCLUSION

No prenatal factor alone firmly predicts neonatal outcome. Clinicians should help stratify the severity of the disease and compare accurately different postnatal therapeutic strategies.

Prenatal diagnosis of dumbbell neuroblastoma

A neuroblastoma that develops in the sympathetic nodes can infiltrate the intervertebral foramina and invade the spinal canal, leading to spinal cord and nerve root compression and neurological impairment. Dumbbell neuroblastomas are now considered to be unresectable tumors and preoperative chemotherapy is recommended. We report the prenatal diagnosis of a dumbbell neuroblastoma successfully managed through premature delivery followed by immediate chemotherapy. We suggest that delivering prematurely in such cases is only of benefit if chemotherapy can be administered under favorable conditions. Chemotherapy should proceed immediately after delivery in order to reduce the size of the tumoral mass and its effects on the spine.

Comparison of fetal lung area to head circumference ratio with lung volume in the prediction of postnatal outcome in diaphragmatic hernia

OBJECTIVES

To compare prediction of postnatal survival in isolated diaphragmatic hernia by prenatal two-dimensional (2D) versus three-dimensional (3D) sonographic assessment of the contralateral lung.

METHODS

The lung area to head circumference ratio (LHR) of the contralateral lung was measured and expressed as a percentage of the normal mean for gestation (O/E) in 47 fetuses with isolated diaphragmatic hernia at 26 (range, 21-36) weeks of gestation. The lung area was measured by tracing the limits of the lungs (LHR trace) and by multiplying the longest diameter by its perpendicular (LHR diameters). The contralateral lung volume was measured by the Virtual Organ Computer-Aided anaLysis method and the O/E was calculated. Regression analysis was used to determine the significance of the LHRs and volume in the prediction of postnatal survival.

RESULTS

The survival rate was 59.6% (28 of 47). There were significant associations between O/E LHR trace and O/E LHR diameters, and between each O/E LHR and O/E volume, but multiple regression analysis demonstrated that significant prediction of survival was provided only by O/E LHR trace and intrathoracic herniation of the liver.

CONCLUSIONS

In diaphragmatic hernia prenatal prediction of postnatal outcome is better by 2D measurement of LHR trace than it is by 3D measurement of lung volume.

Surfactant maturation is not delayed in human fetuses with diaphragmatic hernia

BACKGROUND

Pulmonary hypoplasia and persistent pulmonary hypertension account for significant mortality and morbidity in neonates with congenital diaphragmatic hernia (CDH). Global lung immaturity and studies in animal models suggest the presence of surfactant deficiency that may further complicate the pathophysiology of CDH. However, data about surfactant status in human fetuses with CDH at birth are contradictory. The lack of a chronological study of surfactant content in late pregnancy has been a significant limitation. The appropriateness of administering surfactant supplements to neonates with CDH is therefore a debated question.

METHODS AND FINDINGS

We investigated surfactant content in human fetuses with CDH compared to age-matched fetuses with nonpulmonary diseases used as controls. Concentrations of disaturated phosphatidylcholine and surfactant proteins were found to be similar at a given stage of pregnancy, with both components showing a similar pattern of increase with progressing pregnancy in fetuses with CDH and in control fetuses. Thyroid transcription factor 1, a critical regulator of surfactant protein transcription, similarly displayed no difference in abundance. Finally, we examined the expression of three glucocorticoid-regulated diffusible mediators involved in lung epithelial maturation, namely: keratinocyte growth factor (KGF), leptin, and neuregulin 1 beta 1 (NRG1-beta1). KGF expression decreased slightly with time in control fetuses, but remained unchanged in fetuses with CDH. Leptin and NRG1-beta1 similarly increased in late pregnancy in control and CDH lungs. These maturation factors were also determined in the sheep fetus with surgical diaphragmatic hernia, in which surfactant deficiency has been reported previously. In contrast to the findings in humans, surgical diaphragmatic hernia in the sheep fetus was associated with decreased KGF and neuregulin expression. Fetoscopic endoluminal tracheal occlusion performed in the sheep model to correct lung hypoplasia increased leptin expression, partially restored KGF expression, and fully restored neuregulin expression.

CONCLUSIONS

Our results indicate that CDH does not impair surfactant storage in human fetuses. CDH lungs exhibited no trend toward a decrease in contents, or a delay in developmental changes for any of the studied surfactant components and surfactant maturation factors. Surfactant amounts are likely to be appropriate to lung size. These findings therefore do not support the use of surfactant therapy for infants with CDH. Moreover, they raise the question of the relevance of CDH animal models to explore lung biochemical maturity.

Assessment of lung area in fetuses with congenital diaphragmatic hernia

OBJECTIVE

To compare the intra- and interobserver agreement of three different methods of measuring lung area in fetuses with congenital diaphragmatic hernia (CDH).

METHODS

In 71 fetuses with isolated CDH at 21-33 weeks' gestation, the area of the contralateral lung was assessed by firstly, manual tracing of lung borders, secondly, multiplication of the longest diameter of the lung by its widest perpendicular diameter, and thirdly, multiplication of the anteroposterior (AP) diameter of the lung at the mid-clavicular line by the perpendicular diameter at the midpoint of the AP diameter (AP method). In 30 fetuses the measurements were made by two observers and Bland-Altman analysis was used to compare the measurement agreement and bias for each observer and between the two observers.

RESULTS

The area obtained by the AP method was similar to that obtained by the manual tracing method, but the area by the longest diameter approach was bigger by 34.4% (95% CI, - 2.4% to 71.1%). The 95% confidence intervals of the difference in paired measurements of lung areas by the same observer and by two different observers were narrower in the manual tracing method than in the multiplying diameters methods.

CONCLUSIONS

In CDH the most reproducible measurement of fetal lung area is provided by manual tracing of the limits of the lungs, rather than by multiplication of lung diameters.

Observed to expected lung area to head circumference ratio in the prediction of survival in fetuses with isolated diaphragmatic hernia

OBJECTIVE

To assess the value of antenatally determined observed to expected fetal lung area to head circumference ratio (LHR) in the prediction of postnatal survival in isolated, congenital diaphragmatic hernia (CDH).

METHODS

Two groups of fetuses were examined. The first group included 650 normal fetuses at 12-32 weeks' gestation, and the data collected were used to establish a normal range of observed to expected LHR with gestational age. The second group included the data of a retrospective multicenter study of 354 fetuses with isolated CDH in which the LHR was measured on one occasion at 18-38 weeks' gestation. The patients were divided into those with left-sided CDH with and without intrathoracic herniation of the liver and right-sided CDH. Regression analysis was used to determine the significant predictors of postnatal survival.

RESULTS

In both the normal fetuses and those with CDH the LHR increased but the observed to expected LHR did not change significantly with gestational age. In normal fetuses the mean observed to expected LHR in the left lung was 100% (95% CI, 61-139%) and in the right lung it was 100% (95% CI, 67-133%). In fetuses with CDH the mean observed to expected LHR was 39% (range 7-79%). Regression analysis demonstrated that significant predictors of survival were the observed to expected LHR (odds ratio (OR) 1.09, 95% CI, 1.06-1.12), side of CDH (left side OR 11.14, 95% CI, 3.41-36.39) and gestational age at delivery (OR 1.18, 95% CI, 1.02-1.36).

CONCLUSION

In CDH, the LHR increases while observed to expected LHR is independent of gestational age. In fetuses with both left- and right-sided CDH, measurement of the observed to expected LHR provides a useful prediction of subsequent survival.

Decreased lung fibroblast growth factor 18 and elastin in human congenital diaphragmatic hernia and animal models

RATIONALE

Lung hypoplasia in congenital diaphragmatic hernia (CDH) seems to involve impaired alveolar septation. We hypothesized that disturbed deposition of elastin and expression of fibroblast growth factor 18 (FGF18), an elastogenesis stimulus, occurs in CDH.

OBJECTIVES

To document FGF18 and elastin in human CDH and ovine surgical and rat nitrofen models and to use models to evaluate the benefit of treatments.

METHODS

Human CDH and control lungs were collected post mortem. Diaphragmatic hernia was created in sheep at 85 days; fetal lungs were collected at 139 days (term = 145 days). Pregnant rats received nitrofen at 12 days; fetal lungs were collected at 21 days (term = 22 days). Some of the sheep fetuses with hernia underwent tracheal occlusion (TO); some of the nitrofen-treated pregnant rats received vitamin A. Both treatments are known to promote lung growth.

MEASUREMENTS AND MAIN RESULTS

Coincidental with the onset of secondary septation, FGF18 protein increased threefold in control human lungs, which failed to occur in CDH. FGF18 labeling was found in interstitial cells of septa. Elastin staining demonstrated poor septation and markedly decreased elastin density in CDH lungs. Consistently, lung FGF18 transcripts were diminished 60 and 83% by CDH in sheep and rats, respectively, and elastin density and expression were diminished. TO and vitamin A restored FGF18 and elastin expression in sheep and rats, respectively. TO restored elastin density.

CONCLUSIONS

Impaired septation in CDH is associated with decreased FGF18 expression and elastic fiber deposition. Simultaneous correction of FGF18 and elastin defects by TO and vitamin A suggests that defective elastogenesis may result, at least partly, from FGF18 deficiency.

Antenatal isolated hydronephrosis associated with urinoma

Two cases of prenatally identified urinoma associated with an isolated hydronephrosis are presented, and the pathophysiology and prognosis of this rare condition are discussed. The presence in utero of a peri-renal collection associated with an isolated hydronephrosis seems to be a sign of significant renal dysplasia. These urinomas disappear spontaneously, thus drainage is not necessary, except in the case of compression of surrounding structures. The functional prognosis of these kidneys seems to be most unfavourable.

Prenatal diagnosis and normal outcome of a 46,XX/46,XY chimera: A Case Report

The phenotypic spectrum of 46,XX/46,XY chimeric patients is variable. It ranges from normal male or female genitalia to different degrees of ambiguous genitalia. Chimerism results from the amalgamation of two different zygotes in a single embryo, whereas mosaicism results from a mitotic error in a single zygote. Several other mechanisms resulting in a chimera have been discussed in the literature. Here, we report on a new case of chimerism (46,XX/46,XY) diagnosed at 17 weeks' gestation on amniocentesis performed because of advanced maternal age. Ultrasound examination revealed normal female external genitalia, and a healthy baby girl was delivered at term. We used polymorphic markers spanning the X chromosome and several autosomes in order to identify the genetic mechanism involved. Mosaicism was excluded because of the presence of 3 alleles at 11 autosomal and 4 X chromosome loci. On autosomes, the origin of this third allele was maternal for two pericentromeric markers (located on 2p11.2 band and 8p11.2 band), paternal for six markers and paternal or maternal for the other three markers. On the X chromosome, the origin of the third allele was maternal for all four markers. Thus, two different paternal and maternal haploid sets were observed. These results are compatible with a tetragametic chimera.

Matthew-Wood syndrome: Report of two new cases supporting autosomal recessive inheritance and exclusion ofFGF10 andFGFR2

We describe two fetal cases of microphthalmia/anophthalmia, pulmonary agenesis, and diaphragmatic defect. This rare association is known as Matthew-Wood syndrome (MWS; MIM 601186) or by the acronym "PMD" (Pulmonary agenesis, Microphthalmia, Diaphragmatic defect). Fewer than ten pre- and perinatal diagnoses of Matthew-Wood syndrome have been described to date. The cause is unknown, and the mode of transmission remains unclear. Most cases have been reported as isolated and sporadic, although recurrence among sibs has been observed once. Our two cases both occurred in consanguineous families, further supporting autosomal recessive transmission. In addition, in one family at least one of the elder sibs presented an evocatively similar phenotype. The spatiotemporal expression pattern of the FGF10 and FGFR2 genes in human embryos and the reported phenotypes of knockout mice for these genes spurred us to examine their coding sequences in our two cases of MWS. While in our patients, no causative sequence variations were identified in FGF10 or FGFR2, this cognate ligand-receptor pair and its downstream effectors remain functional candidates for MWS and similar associations of congenital ocular, diaphragmatic and pulmonary malformations.