Repetitive MR measurements of lung volume in fetuses with congenital diaphragmatic hernia: individual development of pulmonary hypoplasia during pregnancy and calculation of weekly lung growth rates.

OBJECTIVE: To investigate individual changes in fetal lung volume (FLV) in fetuses with isolated congenital diaphragmatic hernia (CDH) and to calculate weekly growth rates of the FLV using serial MR examinations during pregnancy. METHODS: MR-FLV was measured in 89 fetuses with CDH. All fetuses received two MRIs. A mean weekly growth rate of the FLV was determined for each fetus and compared with the growth rate of healthy fetuses. RESULTS: Mean observed-to-expected MR-FLV (o/e MR-FLV) measured at the first MRI was 33.3 ± 12.2% and 29.5 ± 10.9% at the second MRI. In 61% of all fetuses (54/89) the o/e MR-FLV decreased during pregnancy, 26% (23/89) showed an increase in the o/e MR-FLV and 13 % (12/89) had stable values. First and last o/e MR-FLV values were significantly associated with mortality and neonatal extracorporeal membrane oxygenation (ECMO) requirement with a higher prognostic accuracy of MR-FLV measurements near delivery. Patients with CDH had lower weekly lung growth rates than healthy fetuses. There was a significant difference in the mean weekly growth rate between survivors and non-survivors and patients with and without ECMO requirement. CONCLUSION: Individual development of FLV in patients with CDH during pregnancy is extremely variable. Follow-up MR-FLV measurements are advisable before deciding upon pre- and postnatal therapeutic options. KEY POINTS: • Lung development in congenital diaphragmatic hernia (CDH) during pregnancy is extremely variable. • MRI demonstrates that lung growth rate is reduced in fetuses with CDH. • The final observed-to-expected fetal lung volume provides the best prognostic information. • Follow-up measurements are advisable before deciding upon therapeutic options.

Fetal lung volume in congenital diaphragmatic hernia: association of prenatal MR imaging findings with postnatal chronic lung disease.

PURPOSE: To assess whether chronic lung disease (CLD) in surviving infants with congenital diaphragmatic hernia (CDH) is associated with lung hypoplasia on the basis of the results of antenatal observed-to-expected fetal lung volume (FLV) ratio measurement at magnetic resonance (MR) imaging. MATERIALS AND METHODS: The study received approval from the institutional review board, with waiver of informed consent for this retrospective review from patients who had previously given informed consent for prospective studies. The ratio of observed to expected FLV at MR imaging was calculated in 172 fetuses with CDH. At postpartum day 28, the need for supplemental oxygen implicated the diagnosis of CLD. At day 56, patients with CLD were assigned to one of three groups-those with mild, moderate, or severe CLD-according to their demand for oxygen. Logistic regression analysis was used to assess the prognostic value of the individual observed-to-expected FLV ratio for association with postnatal development of CLD. RESULTS: Children with CLD were found to have significantly smaller observed-to-expected FLV ratios at MR imaging than infants without CLD (P < .001). Grading of CLD revealed significant differences in observed-to-expected FLV ratio between patients with mild CLD and those with moderate (P = .012) or severe (P = .007) CLD. For an observed-to-expected FLV ratio of 5%, 99% of patients with CDH developed CLD, compared with less than 5% of fetuses with an observed-to-expected FLV ratio of 50%. Perinatally, development and grade of CLD were further influenced by the need for extracorporeal membrane oxygenation (ECMO) (P < .001) and gestational age at delivery (P = .009). CONCLUSION: Manifestation of CLD in surviving infants with CDH is associated with the prenatally determined observed-to-expected FLV ratio. Early neonatal therapeutic decisions can additionally be based on this ratio. Perinatally, ECMO requirement and gestational age at delivery are useful in further improving the estimated probability of CLD.

Congenital diaphragmatic hernia: predictive value of MRI relative lung-to-head ratio compared with MRI fetal lung volume and sonographic lung-to-head ratio.

OBJECTIVE: The purpose of this study was to evaluate the prognostic accuracy of a new MRI-based relative lung-to-head ratio in regard to neonatal survival and need for extracorporeal membrane oxygenation (ECMO) in the care of fetuses with congenital diaphragmatic hernia (CDH) and to compare it with the previously described sonographic relative lung-to-head ratio and relative fetal lung volume assessed at antenatal MRI. MATERIALS AND METHODS: Sonographic lung-to-head ratio and MRI fetal lung volume were measured in 90 fetuses (mean gestational age, 31.4+/-4.1 weeks) with CDH. Sonographic relative lung-to-head ratio and MRI relative fetal lung volume were assessed by expressing the observed sonographic lung-to-head ratio and MRI fetal lung volume as a percentage of the expected parameter value. The new MRI relative lung-to-head ratio was assessed as a percentage of the expected MRI lung-to-head ratio based on MRI fetal lung volume and MRI head circumference measurements. Measurements for survival and ECMO requirement were determined with the area under the curve (AUC). Data were analyzed for left-sided defects, right-sided defects, and associated liver herniation. RESULTS: Among fetuses with left-sided CDH, all parameters were excellent in determining neonatal survival and need for ECMO therapy (p

MR lung volume in fetal congenital diaphragmatic hernia: logistic regression analysis--mortality and extracorporeal membrane oxygenation.

PURPOSE: To prospectively assess the results of logistic regression analysis that were based on magnetic resonance (MR) image fetal lung volume (FLV) measurements to predict survival and the corresponding need for extracorporeal membrane oxygenation (ECMO) therapy in fetuses with congenital diaphragmatic hernia (CDH) before and after 30 weeks gestation. MATERIALS AND METHODS: Written informed consent was obtained and the study was approved by the local research ethics committee. FLV was measured on MR images in 95 fetuses (52 female neonates, 43 male neonates) with CDH between 22 and 39 weeks gestation by using multiplanar T2-weighted half-Fourier acquired single-shot turbo spin-echo MR imaging. On the basis of logistic regression analysis results, mortality and the need for ECMO therapy were calculated for fetuses before and after 30 weeks gestation. RESULTS: Overall, higher FLV was associated with improved survival (P < .001) and decreasing probability of need for ECMO therapy (P = .008). Survival at discharge was 29.2% in neonates with an FLV of 5 mL, compared with 99.7% in neonates with an FLV of 25 mL. The corresponding need for ECMO therapy was 56.1% in fetuses with an FLV of 5 mL and 8.7% in fetuses with an FLV of 40 mL. Prognostic power was considerably lower before 30 weeks gestation. CONCLUSION: Beyond 30 weeks gestation, logistic regression analysis that is based on MR FLV measurements is useful to estimate neonatal survival rates and ECMO requirements. Prior to 30 weeks gestation, the method is not reliable and the FLV measurement should be repeated, particularly in fetuses with small lung volumes, before a decision is made about therapeutic options.

MR relative fetal lung volume in congenital diaphragmatic hernia: survival and need for extracorporeal membrane oxygenation.

PURPOSE: To retrospectively evaluate the accuracy of the absolute fetal lung volume (FLV) measured at magnetic resonance (MR) imaging and seven formulas for calculating relative FLV to predict neonatal survival and the need for extracorporeal membrane oxygenation (ECMO) in fetuses with congenital diaphragmatic hernia (CDH). MATERIALS AND METHODS: This retrospective study was approved by the research ethics committee, and informed consent was received from all mothers for previous prospective studies. In total, 68 fetuses with CDH were assessed by using MR image FLV measurement within 23-39 weeks gestation. The relative FLV was expressed as a percentage of the predicted lung volume calculated with biometric parameters according to seven formulas previously described in the literature. Applying the area under the curve (AUC), the various relative FLVs and the absolute FLV were investigated for their prognostic accuracy to predict neonatal survival and the need for ECMO therapy. RESULTS: All relative FLVs and the absolute FLV revealed a significant difference in mean lung volume between neonates who survived and neonates who did not survive (P = .001 to P < .001) and measurement accuracy was excellent for each method (AUC, 0.800-0.900). For predicting neonatal ECMO requirement, differences in FLVs were smaller but still significant (P = .05 to <.009) and measurement accuracy was acceptable throughout (AUC, 0.653-0.739). CONCLUSION: The various relative FLVs and the absolute FLV measured at MR planimetry are each highly valuable in predicting survival in fetuses with CDH. For predicting whether neonatal ECMO therapy is required, the accuracy of the absolute FLV (AUC, 0.68) and that of the relative FLVs (AUC, 0.653-0.739) was acceptable.

Reliability and validity of MR image lung volume measurement in fetuses with congenital diaphragmatic hernia and in vitro lung models.

PURPOSE: To prospectively assess the reliability of magnetic resonance (MR) image volume measurement in fetuses with congenital diaphragmatic hernia (CDH) and the reliability and validity of measurements in in vitro lung models. MATERIALS AND METHODS: This study was approved by the ethics committee, and informed consent was obtained. MR fetal lung volume (FLV) was measured in 40 consecutive fetuses with CDH by using half-Fourier acquired single-shot turbo spin-echo MR imaging and true fast imaging with steady-state precession at 24-36 weeks gestation (mean gestational age, 30.6 weeks +/- 3.5 [standard deviation]). Lung volumes were independently assessed in three orthogonal section planes by two experienced observers. Additionally, 28 in vitro lung models of defined volumes of 1-60 mL were evaluated the same way. To assess measurement validity and reliability, the intraclass correlation coefficient (ICC) and the Bland-Altman plot were used. RESULTS: The interobserver reliability was high for both the lung models and FLV measurements (ICC, 0.999 and 0.928, respectively). Measurement validity was also good, with a mean difference between the calculated volume and the true volume of 0.4 mL (95% confidence interval: 0.30, 0.48). Measurement reliability and validity did not depend, to any considerable degree, on imaging plane or sequence (ICC range, 0.878-0.999) or on total volume. CONCLUSION: The reliability and validity of MR volume measurements are high. The method is independent of the sequence and the imaging plane and can be performed with a very good interobserver agreement, even in small volumes.

Extracorporeal membrane oxygenation in infants with congenital diaphragmatic hernia: follow-up MRI evaluating carotid artery reocclusion and neurologic outcome.

OBJECTIVE: The purpose of our study was to prospectively assess, using MRI and MR angiography, the cerebral and vascular status of 2-year-old children with congenital diaphragmatic hernia (CDH) in whom carotid artery reconstruction was performed after neonatal extra-corporeal membrane oxygenation (ECMO) therapy and to compare the neurologic development of children with vascular reocclusion with that of CDH children with successful repair and with non-ECMO controls. SUBJECTS AND METHODS: A total of 30 infants (17 boys, 13 girls; 2 +/- 0.26 years) were included. Of these, 18 (60%) infants received arteriovenous ECMO therapy with subsequent reconstruction of the right common carotid artery (RCCA). Two years postoperatively, the children were examined with cerebral MRI, including 3D time-of-flight and contrast-enhanced 3D MR angiography of the intra- and extracranial brain-supplying arteries. The pathologic findings were analyzed for the ability to predict impaired neurologic development. RESULTS: The RCCA was occluded or highly stenotic in 13 (72%) of 18 children. All infants showed intra- and extracranial collaterals and a patent internal carotid artery. The average duration of ECMO was not longer than in cases of successful reconstruction (p = 1). The ECMO group showed a significantly greater incidence of cerebral injuries (p = 0.007) but no relevant impairment in neurologic development compared with controls (p = 0.26). Unsuccessful RCCA repair had no predictive value for a poor neurologic outcome (p = 1). CONCLUSION: The outcome of RCCA repair after ECMO is possibly poorer than expected, with vascular occlusion or high-grade stenosis occurring in almost three quarters of patients. Although reocclusion of the RCCA does not increase the risk for cerebral lesions or an impaired neurologic development during the first 2 years postoperatively, the overall benefit of RCCA repair remains doubtful, and the potential long-term risk arising from these plaques has yet to be assessed.

Prediction of mortality and need for neonatal extracorporeal membrane oxygenation in fetuses with congenital diaphragmatic hernia: logistic regression analysis based on MRI fetal lung volume measurements.

OBJECTIVE: The purpose of this study was to use logistic regression analysis of prenatal MRI fetal lung volume measurements to calculate mortality and the need for extracorporeal membrane oxygenation (ECMO) therapy among fetuses with congenital diaphragmatic hernia (CDH). SUBJECTS AND METHODS: The fetal lung volume measurements of 65 fetuses with CDH were obtained between 32 and 34 weeks' gestation by means of MRI performed with multiplanar T2-weighted HASTE and true fast imaging with steady-state precession sequences. Logistic regression analysis was used to assess the prognostic value of the fetal lung volume measurements for prenatal prediction of fetal survival and need for neonatal ECMO. RESULTS: Fetal lung volume was a highly significant predictor of survival (p < 0.0001) and neonatal ECMO requirement (p = 0.0006). The mortality was 84% and the ECMO requirement 80% among fetuses with a lung volume of 5 mL. The mortality was 0.4% and the ECMO requirement 20% among patients with a fetal lung volume of 30 mL. CONCLUSION: Logistic regression analysis of MRI fetal lung volume measurements is highly valuable in predicting mortality among neonates with CDH, and it may help to estimate the need for neonatal ECMO. The method is feasible for facilitating parental guidance and may help in choosing postnatal therapeutic options, including ECMO therapy.