Fetal Lung Volume Measurement Research Articles

Expression of Concern: The role of three-dimensional ultrasonography fetal lung volume measurement in the prediction of neonatal respiratory function outcome

Expression of Concern: The role of three-dimensional ultrasonography fetal lung volume measurement in the prediction of neonatal respiratory function outcome

Automatic measurement of fetal lung volume by 3D ultrasound based on 3D-nnUnet

Fetal lung dysplasia often causes the severe respiratory distress and even neonatal death at birth. Fetal lung volume measurement is an important method for clinical non-invasive assessment of lung maturity. However, the existing methods for measuring fetal lung volume suffer from huge errors, tedious and time-consuming operations, and poor clinical practicability. For this reason, we first propose an efficient and stable automatic segmentation and measurement method for fetal lung volume based on 3D-nnUnet, which uses the network adaptation to effectively overcome the problems of low tissue contrast and blurred edges and achieves accurate segmentation of 3-dimensional (3D) fetal lung ultrasound images. In addition, to solve the problem of large difference and extremely uneven distribution of sample numbers at different gestational weeks, we innovatively propose a hard-mining and easy-penalized (HMEP) loss to improve the model generalization ability. Compared with the segmentation results of 2-dimension optimal DeepLab V3+ and 3D-Unet, our network model has the best segmentation performance, and the accuracy is as high as 85.7%. In addition, HMEP loss enables the 3D-nnUnet model to focus on learning a few difficult samples, which increases the segmentation accuracy by nearly 2%. There is no significant statistical difference between the fetal lung volumes measured by our network and gold standard using the consistency test in different gestational weeks. The experimental results show that our method can efficiently realize the automatic and accurate segmentation and volume measurement of 3D ultrasound fetal lung, and has the good stability and generalization ability, which can avoid the problems of cumbersome, time-consuming operations and large errors in the previous fetal lung volume measurement methods. Our method has the promising application prospects in diagnosing fetal lung dysplasia and assessing fetal lung maturity.

Innovative approach for first-trimester fetal organ volume measurements using a Virtual Reality system: The Generation R Next Study.

IntroductionTo investigate the reproducibility of first‐trimester fetal organ volume measurements using three‐dimensional (3D) ultrasound and a Virtual Reality system.MethodsWithin a population‐based prospective cohort study, 3D ultrasound datasets of 25 first‐trimester fetuses were collected by three sonographers. We used the V‐scope application to perform Virtual Reality volume assessments of the fetal heart, lungs, and kidneys. All measurements were performed by two independent researchers.ResultsIntraobserver analyses for volume measurements of the fetal heart, lungs, and kidneys showed intraclass correlation coefficients ≥0.86, mean differences ≤8.3%, and coefficients of variation ≤22.8%. Interobserver analyses showed sufficient agreement for right lung volume measurements, but consistent measurement differences between observers for left lung, heart, and kidney volume measurements (p‐values <0.05).ConclusionWe observed sufficient intraobserver reproducibility, but overall suboptimal interobserver reproducibility for first‐trimester fetal heart, lung, and kidney volume measurements using an innovative Virtual Reality approach. In the current stage, these measurements might be promising for the use in research settings. The reproducibility of the measurements might be further improved by novel post‐processing algorithms.

Fetal Thoracic Circumference and Lung Volume and Their Relation to Fetal Size and Pulmonary Artery Blood Flow.

Research on early origins of lung disease suggests the need for studying the relationships of thoracic and lung size with fetal size and pulmonary circulation. The primary aim of this study is therefore to explore the associations between fetal thoracic circumference, lung volume, and fetal size. We also aim to assess if lung volume and thoracic circumference are associated with fetal pulmonary artery blood flow velocity measures. Cross-sectional assessment of singleton pregnancies from the general population (n=447) at 30 gestational weeks (GW) was performed using ultrasound measurement of fetal thoracic circumference, lung volume, head and abdominal circumference, and femur length. We obtained Doppler blood flow velocity measures from the proximal branches of the fetal pulmonary artery. Associations between variables were studied using Pearson's correlation and multiple linear regression analyses. Both thoracic circumference and lung volume correlated with fetal size measures, ranging from r=0.64 between thoracic circumference and abdominal circumference, to r=0.28 between lung volume and femur length. Adjustment for gestational age, maternal nicotine use, pre-pregnancy body mass index, and fetal sex marginally influenced the associations with abdominal circumference. The correlations of thoracic circumference and lung volume with pulmonary artery blood flow velocity measures were weak (r ≤ 0.17). We found moderate to low correlation between thoracic circumference, lung volume, and fetal size at 30 GW. The closest relationship was with the abdominal circumference. We found low correlations of thoracic circumference and lung volume with pulmonary artery blood flow velocity measures.

Cost-effective fetal lung volumetry for assessment of congenital diaphragmatic hernia

Objectives(1) To investigate the reproducibility of total fetal lung volume (TFLV) measurements using a free 3D modeling software (3DSlicer); (2) To correlate these measurements with lung-to-head ratio (LHR) or TFLV measured using PACS and; (3) To determine the role of 3DSlicer in predicting perinatal outcomes in cases with congenital diaphragmatic hernia (CDH) who had fetal tracheal occlusion (FETO). MethodsRetrospective cohort study between 2012 and 2017 at Texas Children’s Hospital (2011–2017), including all patients who underwent FETO for CDH. LHR was measured by ultrasound and TFLV was measured by MRI at the time of referral and 6 weeks after FETO using 3DSlicer and PACS. We evaluated intra- and inter-rater reliability of TFLV measurement using 3DSlicer, infant survival to 1 year, need for ECMO and pulmonary hypertension. ResultsThe intra- and inter-rater reliability of TFLV measured with 3DSlicer was excellent before and after FETO (Intra-class correlation coefficient: 0.98−0.99 and 0.94−0.99, respectively). There was a good correlation between TFLV measured with PACS and with 3DSlicer before and after FETO (r = 0.78 and r = 0.99, respectively). Similarly, there was a good correlation between TFLV measurements using PACS or 3DSlicer and LHR after FETO (r = 0.86 and r = 0.88, respectively). Infants who survived to 1 year had a significantly higher TFLV evaluated with 3DSlicer before FETO compared to non-surviving infants (OR = 1.16[1.1–1.3], p = 0.03) as well as a significantly higher TFLV evaluated by 3DSlicer after FETO (OR = 1.2[1–1.4], p = 0.04). ConclusionLung volume measurements using free 3DSlicer in infants with severe CDH who underwent FETO are reproducible and reliable, and have comparable predictive capability for survival as those measured using conventional software.

Prenatal assessment of congenital diaphragmatic hernia at north american fetal therapy network centers: A continued plea for standardization.

Prenatal work-up for congenital diaphragmatic hernia (CDH) is important for risk stratification, standardization, counseling, and optimal therapeutic choice. To determine current practice patterns regarding prenatal CDH work-up, including prenatal ultrasound and magnetic resonance imaging (MRI) use, and to identify areas for standardization of such evaluation between fetal centers. A survey regarding prenatal CDH work-up was sent to each member center of the North American Fetal Therapy Network (NAFTNet) (n = 36). All responded. Sonographic measurement of lung-to-head ratio (LHR) was determined by all, 89% (32/36) of which routinely calculate observed-to-expected LHR. The method for measuring LHR varied: 58% (21/36) used a "trace" method, 25% (9/36) used "longest axis," and 17% (6/36) used an "antero-posterior" method. Fetal MRI was routinely used in 78% (28/36) of centers, but there was significant variability in fetal lung volume measurement. Whereas all generated a total fetal lung volume, the planes, methodology and references values varied significantly. All evaluated liver position, 71% (20/28) evaluated stomach position and 54% (15/28) quantified the degree of liver herniation. More consistency in workup was seen between centers offering fetal intervention. Prenatal CDH work-up and management differs considerably among North American fetal diagnostic centers, highlighting a need for its standardization.

Standard Normal Fetal Lung Volume by MRI Measurement

Background: Pulmonary hypoplasia is a significant decrease in lung volume by any cause in comparison to the normal volume for gestational age. Objectives: To evaluate the application of prenatal magnetic resonance imaging in order to predict pulmonary hypoplasia, measurement of fetal lung volume (FLV) was aimed to establish a reference data in normal fetuses. Patients and Methods: Three hundred forty two fetuses with abnormal ultrasound findings underwent fast spin-echo T2-weighted MR imaging at a single tertiary care hospital (Shahid Faghihi Hospital, Shiraz, Iran). Data of 241 fetuses at 18 - 36 weeks’ gestation without thoracic malformations were obtained for a FLV normative curve. To acquire a best-fit formula for the mean total fetal lung volume based on each gestational week with 95% confidence interval (CI), we used the regression model applied by Rypens et al. This resulted in a formula calculating the expected fetal lung volume based on gestational age. A one-sample t-test was also carried out to compare the mean total fetal lung volume at each gestational week with the expected mean total fetal lung volume predicted by the formula by Rypens et al., Meyers et al., and Osada et al. Results: Normal FLV increased with gestational age as the spread of values. The expected fetal lung volume was derived from the following formula: Fetal lung volume (mL) = 0.002 × (gestational age [GA]2.913), in which GA is gestational weeks. FLV in our population had a more consistent correlation with Japanese fetuses than European or American fetuses. Conclusion: In fetuses with normal lungs, FLV distribution against gestational age is simply measured prenatally with MR imaging. A single universal formula might not be suitable for fetuses worldwide. In our region, acquired data were more consistent with Asian normal values.

Combined measurement of fetal lung volume and pulmonary artery resistance index is more accurate for prediction of neonatal respiratory distress syndrome in preterm fetuses: a pilot study

Objective: The objective of this study is to estimate optimal cut-off values for mean fetal lung volume (FLV) and pulmonary artery resistance index (PA-RI) as non-invasive measures to predict neonatal respiratory distress syndrome (RDS) in preterm fetuses.Methods: A prospective study conducted at Ain Shams University Maternity Hospital, Egypt from May 2015 to July 2017: 80 eligible women diagnosed with preterm labor were recruited at 32–36 weeks’ gestation. Before delivery, three-dimensional ultrasound was used to estimate FLV using virtual organ computer-aided analysis (VOCAL), while PA-RI was measured by Doppler ultrasonography.Results: A total of 80 women were examined. Thirty-seven (46%) of the newborns developed neonatal RDS. FLV was significantly lower in neonates who developed RDS (p = .04), whereas PARI was significantly higher in those who did not (p = .02). Cut-off values of FLV ≤27.2 cm3 and PARI ≥0.77 predicted the subsequent development of RDS. Combining both cut-offs generated a more sensitive and specific methodical approach for the prediction of RDS (sensitivity 100%, specificity 88.5%).Conclusion: Measurement of FLV or PA-RI can predict RDS in preterm fetuses. Combined use of both measures bolstered their predictive significance.

The role of three-dimensional ultrasonography fetal lung volume measurement in the prediction of neonatal respiratory function outcome

Background: Respiratory distress is commonly encountered among premature babies immediately after birth resulting in significant neonatal morbidity or mortality. Objectives: To evaluate the possible correlation between three dimensional fetal lung volumes (FLVs) and neonatal respiratory outcomes. Study design: A cohort study included 100 pregnant women who participated in the study and were divided into two groups; group A (n: 50 – women pregnant ±34–37 weeks) and group B (n: 50 – women pregnant ±37+1 to 40 weeks). A three dimensional measurement of the right fetal lung was made using virtual organ computer-aided analysis (VOCAL) software then correlated to neonatal respiratory functions namely Apgar score at birth and the occurrence of respiratory distress syndrome (RDS). Results: In group A, FLV was negatively correlated with Apgar score and the occurrence of RDS. In group B, FLV showed no statistical correlation with Apgar score and the occurrence of RDS. Conclusions: Three dimensional fetal lung volumes might be an accurate noninvasive predictor for the development of RDS among preterm fetuses.

Prediction of lethal pulmonary hypoplasia by means fetal lung volume in skeletal dysplasias: a three-dimensional ultrasound assessment

Objective: The aim of this study was to assess the capacity of three-dimensional ultrasound (3DUS) for predicting lethality in fetuses with skeletal dysplasia.Methods: Twenty-four fetuses between 20 and 32 weeks of gestation were assessed. Bilateral lung volume scans were performed three times in each fetus during one ultrasound session. The virtual organ computer-aided analysis method was used to obtain a sequence of six sections of each lung around a fixed axis, and a rotation angle of 30° was adopted. Fetal lung volume measurements were analyzed according to the reference range. After birth, lung hypoplasia was diagnosed considering clinical and radiological criteria.Results: Of all cases of skeletal dysplasia, 18 (75%) were lethal. Among the lethal cases, after postnatal diagnosis, four were osteogenesis imperfecta type II, three were thanatophoric dysplasia and two were campomelic dysplasia. The remaining nine cases remained without a definitive diagnosis. The accuracy of 3DUS in predicting lethality in fetuses with skeletal dysplasia was high, with a sensitivity of 83.3%, specificity of 100%, positive predictive value of 100% and negative predictive value of 66.7%. The kappa index of 0.174 showed a good agreement between the possibility of lethality when the 3DUS volume measurement was altered and real lethality after birth (p < 0.001).Conclusion: This study suggests that the 3DUS lung volume measurement is a good predictor of lethal pulmonary hypoplasia in fetuses with skeletal dysplasia, with high accuracy.

Fetal lung volume assessment based on 3-dimensional prenatal ultrasound

Objective To measure fetal lung volumes in different gestational age (GA) by using 3D ultrasound,and further to obtain the regression formula between fetal lung volume and GA.Methods Total 228 fetal lung data had been collected.By using the 3D reconstruction function in Philips Qlab,fetal lung volumes were obtained by subtracting the non lung volumes from the whole thoracic volumes.For each slice of 3D data,thoracic area and non-lung area were manually outlined.The contour stacking technique in Qlab was then used to transform 2D slices into 3D volumes.Results The measurement results of total 228 cases indicate that the fetal lung volumes increase with the GA.The average lung volume at GA of 20 weeks was 8.85 cm3,and 70.5 cm3 at 36 weeks.The fetal lung volume increases about 3- 4 cm3 in each week,and the increasing trend turns to a little lower after 24 weeks.During 33 to 34 week there was a great increasing in fetal volumes.Second-order regression,exponential regression and logarithmic regression were respectively used to characterize the relationship between fetal lung volume and GA.The second-order regression formula was:Volume =39.52 - 4.48 × GA + 0.149 × GA2.The exponential regression formula was:Ln (Volume) =- 8.233 + 1.747 × Ln(GA2 ).The logarithmic regression formula was:Ln(Volume) =- 2.413 + 0.29× GA- 0.003 × GA2.The correlation coefficients of three formulas are equal,with r =0.99,P ＜ 0.001.Conclusions 3D ultrasound fetal lung volume measurement is useful for fetal lung maturity assessment and thus can provide important referential information for prenatal diagnosis. Key words: Ultrasonography,prenatal; Lung; Volume

Two‐ or three‐dimensional ultrasonography: which is the best predictor of pulmonary hypoplasia?

The aim of our study is to compare the three-dimensional (3D) ultrasound fetal lung volume measurements with two-dimensional (2D) ultrasound biometric parameters in predicting pulmonary hypoplasia (PH). From June 2006 to November 2008, we identified 35 fetuses at high risk for developing PH, including premature preterm rupture of membranes (17), fetal skeletal malformations (7), hydrothorax (7), and bilateral renal dysplasia (4). 3D lung volumes adjusted for gestational age (GA) or estimated fetal weight (EFW), thoracic circumference adjusted for GA or femur length, thoracic/abdominal circumference ratio, and thoracic/heart area ratio were measured. Three infants were excluded because no clinical or histological information regarding lung hypoplasia was available. Of the 32 remaining infants, 13 (41%) were diagnosed with PH at postmortem examination or by clinical and radiological examination. 3D lung volume measurements had a better diagnostic accuracy for predicting PH either when adjusted for GA [sensitivity, 12/13 (92%); specificity, 16/19 (84%); positive predictive value 12/15 (80%); negative predictive value, 16/17(94%)] or EFW [sensitivity, 11/13 (85%); specificity, 18/19 (94%); positive predictive value 11/12(92%); negative predictive value, 18/20(90%)] compared to the 2D biometric measurement. 3D lung volume measurements seem to be useful in the prenatal prediction of PH.

OP04.01: The fetal cardiovascular response to an increased placental vascular resistance (PVR) measured with STIC and VOCAL

the left lung, and R2 = 0,937 to the total lung volume). The lung volume also proved to be highly related to fetal weight (R2 = 0,905 to the right lung, R2= 0,84to the left lung, and R2 = 0,908 to the total lung volume). The intra-observer variability study was of 0,990 for the right lung, 0,986 for the left lung, and 0,995 for the total lung volume. The value of Cronbach Alfa Coefficient to evaluate the inter-observer variability was 0,975 for the right lung, and 0,962 for the left lung. Conclusion: the fetal lung volume measurement by VOCAL method of 3-dimensional unltrasonography shows good reproducibility and can be utilized to evaluate fetal lung growth.

Congenital Diaphragmatic Hernia: Predictive Value of MRI Relative Lung-to-Head Ratio Compared with MRI Fetal Lung Volume and Sonographic Lung-to-Head Ratio

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. 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. Among fetuses with left-sided CDH, all parameters were excellent in determining neonatal survival and need for ECMO therapy (p <or= 0.0027). Prognostic accuracy was best for the newly devised MRI relative lung-to-head ratio (AUC, 0.816 and 0.807) and lowest for sonographic relative lung-to-head ratio (AUC 0.783 and 0.703). Among fetuses with right-sided defects, the predictive value was lower for all parameters (AUC, 0.788-0.560). All neonates without liver herniation survived. Among fetuses with left-sided CDH, assessment of pulmonary hypoplasia based on MRI relative fetal lung volume and MRI relative lung-to-head ratio is excellent in prediction of neonatal survival and ECMO requirement. The prognostic accuracy is slightly better than that of sonographic relative lung-to-head ratio. Among fetuses with right-sided CDH, the prognostic value of all parameters is lower than those among fetuses with left-sided defects.

MR Lung Volume in Fetal Congenital Diaphragmatic Hernia: Logistic Regression Analysis—Mortality and Extracorporeal Membrane Oxygenation

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. 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. 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. 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

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). 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. 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). 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, repeatability and reproducibility: analysis of measurement errors in continuous variables

Reliability, repeatability and reproducibility: analysis of measurement errors in continuous variables

Comparison of the two-dimensional and multiplanar methods and establishment of a new constant for the measurement of fetal lung volume

Objectives. To compare the two-dimensional (2D) and multiplanar methods in the measurement of lung volume in normal fetuses, to obtain a new constant to be incorporated into the 2D equation, and to apply the new equation in fetuses with pulmonary hypoplasia (PH) confirmed postnatally.Methods. A cross-sectional study was performed on 51 pregnant women at between 20 and 35 weeks of gestation. The ellipsoid formula (x × y × z × 0.52) was used to calculate lung volume by the 2D method. A sequence of multiple planes with 2.0-mm intervals was used with the multiplanar method. In order to compare the techniques, the intra-class correlation coefficient (ICC) and the Student's t-test (p) were used. First-order linear regressions were used to establish a new constant, with three-dimensional (3D) lung volume as dependent variable and gestational age and 2D volume as independent variables. In order to validate it, the new equation was applied to 11 fetuses with confirmed lethal PH.Results. The mean volumes obtained by the 2D method were overestimated when compared to the multiplanar method (right lung: 23.87 vs. 18.26 mL, respectively, p < 0.001 and left lung: 16.18 vs. 14.33 mL, respectively, p = 0.008). Using a first-order polynomial regression, new constants were obtained for the right lung (0.152) and for the left lung (0.167). When compared to the traditional formula, the new equation presented higher sensitivity (18.1%) in predicting lethal PH.Conclusion. The recalculated 2D equation can be a promising alternative to 3D ultrasonography in the prediction of PH.

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

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). 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. 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. 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.

Reliability and Validity of MR Image Lung Volume Measurement in Fetuses with Congenital Diaphragmatic Hernia and in Vitro Lung Models

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. 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. 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. 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.