Two- or three-dimensional ultrasonography to predict pulmonary hypoplasia in pregnancies complicated by preterm premature rupture of the membranes

Imagiological methods for prediction of fetal pulmonary hypoplasia: a systematic review

OBJECTIVE

To compare the different imagiological methods for prediction of fetal pulmonary hypoplasia (PH) in general diseases and associated with preterm rupture of membranes (PROM), and congenital diaphragmatic hernia (CDH).

METHODS

According to PRISMA guidelines, all the literature on PH from 1988 to 2018 was reviewed. Twenty-nine articles were selected and analyzed for two- and three- dimensional-ultrasounds (2D and 3D-US) as predictors for the lethal outcome.

RESULTS

Overall, the results identify a general gap correlating prenatal pulmonary measurements and survival at birth; discrepant predictive values for the same imagiological methods are explained by the group heterogeneity in terms of diseases and degree of severity, with the 2D measurements being more affected than 3D; 2D and 3D-US present equally predictive values for groups with 0% of survival. Regarding PROM, results demonstrate comparable accuracies for similar survival rates suggesting a useful predictive value of 2D-US in outcome estimation; they also identify ultrasonographic methods as a more accurate prognostic factor than gestational age at rupture, latency or amniotic fluid index. In CDH, consistent with previous studies, our review shows magnetic resonance imaging as a better survival predictor followed by the 3D and 2D methods, while 2D-LHR was the more precise prognosticator correlating prenatal PH, survival at birth, and the need for neonatal respiratory support.

CONCLUSION

Ultrasonographic methods can be valuable predictors for lethal PH and should be validated for a broad set of diseases (e.g. PROM). For that, restricted studies for disease groups and correlating fetal PH with the needed of neonatal support, and survival at birth is critically recommended.

Parameters of fetal pulmonary vascular health: baseline trends and response to maternal hyperoxia in the second and third trimesters

OBJECTIVES

Several parameters, including branch pulmonary artery (PA) diameter and Doppler-derived PA acceleration-to-ejection time ratio (AT/ET), peak late-systolic/early-diastolic reversed flow (PEDRF) and pulsatility index (PI) response to maternal hyperoxia, have been used to investigate fetal pulmonary health. Lower AT/ET, increased PEDRF and lack of PI response to hyperoxia have been observed in fetuses with severe lung hypoplasia and are considered markers of pulmonary vascular resistance. We sought to further define the evolution of PA diameter and Doppler parameters and their response to maternal hyperoxia in healthy fetuses.

METHODS

Fifty-four prospectively recruited women with healthy pregnancy underwent fetal echocardiography from 18-36 weeks of gestation. After baseline branch PA diameter and Doppler assessment, oxygen (8-10 L/min) was administered by non-reservoir facemask for 10 min and PA Doppler parameters were reassessed.

RESULTS

Branch PA diameters and AT/ET increased linearly with gestational age, while PEDRF increased quadratically (P < 0.001 for all) and PA-PI did not change. In response to maternal hyperoxia, although most fetuses demonstrated a significant decrease in PI for both branch PAs (right PA, P = 0.025; left PA, P = 0.040) ≥ 30 weeks, significant variability was observed in PI response with 31% of cases demonstrating either no response or a slight decrease. No other parameter demonstrated a measurable change in response to maternal hyperoxia.

CONCLUSIONS

From the mid-trimester, fetal branch PA diameters and AT/ET increase linearly and PEDRF increases quadratically, whereas PI remains unchanged. Although maternal hyperoxia triggers a significant decrease in PA-PI after 30 weeks, variability in this response may reduce its utility in clinical practice. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

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.

Accuracy of imaging parameters in the prediction of lethal pulmonary hypoplasia secondary to mid-trimester prelabor rupture of fetal membranes: a systematic review and meta-analysis

In women who have suffered mid-trimester prelabor rupture of membranes (PPROM), prediction of pulmonary hypoplasia is important for optimal management. We performed a systematic review to assess the capacity of imaging parameters to predict pulmonary hypoplasia. We searched for published articles that reported on biometric parameters and allowed the construction of a 2 × 2 table, comparing at least one of these parameters with the occurrence of pulmonary hypoplasia. The selected studies were scored on methodological quality and we calculated sensitivity and specificity of the tests in the prediction of pulmonary hypoplasia and lethal pulmonary hypoplasia. Overall performance was assessed by summary receiver-operating characteristics (sROC) analyses that were performed with bivariate meta-analysis. We detected 13 studies that reported on the prediction of lethal pulmonary hypoplasia. The quality of the included studies was poor to mediocre. The estimated sROC curves for the chest circumference/abdominal circumference ratio and other parameters showed limited accuracy in the prediction of pulmonary hypoplasia. In women with mid-trimester PPROM, the available evidence indicates limited accuracy of biometric parameters in the prediction of pulmonary hypoplasia.

Fetal lung volume in fetuses with urinary tract malformations: comparison by 2D-, 3D-sonography and magnetic resonance imaging

OBJECTIVE

To evaluate the concordance between two-dimensional ultrasonography (2DUS), three-dimensional ultrasonography (3DUS) and magnetic resonance imaging (MRI) in the assessment of lung volume in fetuses with urinary tract malformations (UTM).

METHODS

This was a cross-sectional study involving 12 pregnancies between 19 and 34 weeks, with various fetal UTM. Pulmonary volume was obtained by 2DUS using the following equation: total lung volume = [right lung antero-posterior diameter (X) x transverse diameter (Y) x cranial-caudal diameter x 0.152 + left lung (X1) x (Y1) x (Z1) x 0.167]. Pulmonary volume by 3DUS was obtained using the virtual organ computer-aided analysis (VOCAL) method with a 30 degrees (VOL30), 18 degrees (VOL18) and 12 degrees (VOL12) rotation. A fast sequence of transverse lung section was also obtained by MRI. The intraclass correlation coefficient was used to evaluate the correlation between the three methods. The paired student t-test was used to compare the means.

RESULTS

There was a strong correlation between the three methods, and the highest correlations were between MRI and VOL18 for the right (ICC = 0.913) and left (ICC = 0.947) lungs. A strong correlation was also found between the lung volumes obtained through MRI and VOL12 as well as VOL18 (p = 0.544 and 0.286, respectively). However, for the left lung there was only a correlation between MRI and VOL12 (p = 0.49).

CONCLUSIONS

There is a good concordance between 3DUS (VOL12) and MRI in the evaluation of lung volume in fetuses with UTM.

The incidence rate of premature rupture of membranes and its influence on fetal-neonatal health: a report from mainland China

Premature rupture of membranes (PROM) is a common pregnancy complication and is associated with significant risks of fetal and neonatal morbidity and mortality. However, there is a lack of data concerning PROM in China. We investigated the incidence rate and analysed the influence of PROM on fetal and neonatal health. This used data from five specialist hospitals and one general hospital in mainland China. The total number of deliveries and the number of those complicated by PROM were recorded between January 2003 and December 2007. The time from initiation of PROM until delivery (latent period), the volume of amniotic fluid at delivery, fetal conditions and neonatal clinical conditions were recorded. The results suggest that the incidence of PROM was 19.53% and it could influence various aspects of the health of fetuses and neonates, including platelet parameters, erythrocyte parameters, neonatal jaundice and myocardial injury.

The management of preterm premature rupture of the membranes near the limit of fetal viability

Preterm premature rupture of the membranes near the limit of fetal viability is an uncommon complication of pregnancy, affecting approximately 4 in 1000 gravidas. However, maternal, fetal, and neonatal complications resulting from this condition are significant and include chorioamnionitis, pulmonary hypoplasia, restriction deformities, fetal loss, and complications of extreme prematurity among surviving infants. In this article, we review the literature regarding pregnancy outcomes after preterm premature rupture of the membranes near the limit of viability, and the data on traditional and nontraditional interventions to improve outcomes. An approach to patients who present with preterm premature rupture of the membranes near the limit of viability will be proposed.

Photogrammetry of fetal breathing movements during the third trimester of pregnancy: observations in normal and abnormal pregnancies

OBJECTIVE

To evaluate parameters of fetal breathing movements-displacement of the fetal abdominal wall during inspiration and expiration, time of inspiration and expiration and speed of inspiration and expiration-between 30 and 36 weeks' gestation in normal pregnancies, and in those complicated by gestational diabetes or maternal hypertension.

METHODS

Three categories of pregnancy were investigated: 49 were normal, 16 had pregnancy-induced diabetes and 10 were hypertensive. According to their gestational age, the patients were divided into two groups: Group A between 30 and 32 weeks' gestation and Group B between 33 and 36 weeks. Using photogrammetry and a computer-operated algorithm, six parameters of fetal breathing movements were investigated.

RESULTS

There were significant differences in the various fetal parameters measured among the three categories of pregnant women. Up until 32 weeks of gestation, the displacements during inspiration and expiration were larger, the speeds of inspiration and expiration were higher, and the times for inspiration and expiration were shorter in the diabetic and hypertensive groups than in the normal group. In the later period, between 33 and 36 weeks, fetuses of pregnancy-induced diabetic patients showed the lowest inspiration and expiration times and the highest speeds of inspiration and expiration.

CONCLUSIONS

Photogrammetry in conjunction with a computer-operated algorithm can be used to assess fetal breathing movements. There are significant differences in fetal breathing movements between normal pregnancies and those that are complicated by gestational diabetes or hypertension.

Predicting pulmonary hypoplasia with 2- or 3-dimensional ultrasonography in complicated pregnancies

OBJECTIVE

The aim of this study was to compare 3-dimensional (3D) lung volume measurements with 2-dimensional (2D) biometric parameters in predicting pulmonary hypoplasia in complicated pregnancies.

STUDY DESIGN

In this prospective study, 1-4 scans of the fetal lungs were obtained in 33 pregnancies complicated by various disorders or complications with regard to pulmonary hypoplasia. The 3D lung volumes vs gestational age or estimated fetal weight, the thoracic circumference vs gestational age or femur length, the thoracic/abdominal circumference ratio, and the thoracic/heart area ratio were measured.

RESULTS

Of the 33 infants, 16 (48.5%) were diagnosed with pulmonary hypoplasia on postmortem examination or the clinical and radiological presentation. Three dimensional lung volume measurements had a better diagnostic accuracy for predicting pulmonary hypoplasia (sensitivity, 94%; specificity, 82%; positive predictive value [PPV], 83%; negative predictive value [NPV], 93%), compared with the best 2D biometric measurement thoracic/heart area ratio (sensitivity, 94%; specificity, 47%; PPV, 63%; NPV, 89%).

CONCLUSION

3D lung volume measurements seem to be useful in predicting pulmonary hypoplasia prenatally.