The correlation between lung volume and liver herniation measurements by fetal MRI in isolated congenital diaphragmatic hernia: a systematic review and meta-analysis of observational studies † Steffi Mayer 1,2 , Philipp Klaritsch 1 , Scott Petersen 1 , Elisa Done 1,3 , Inga Sandaite 3,4 , Holger Till 2 , Filip Claus 4 and Jan A. Deprest 1,3 * 1 Centre for Surgical Technologies, Faculty of Medicine, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium 2 Department of Paediatric Surgery, University Hospital Leipzig, D-40103 Leipzig, Germany 3 Department of Obstetrics and Gynaecology, Division Woman and Child, Fetal Medicine Unit, University Hospital Gasthuisberg, B-3000 Leuven, Belgium 4 Department of Radiology, Division of Medical Imaging, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium Objective We conducted a meta-analysis to assess the correlation of lung volume and liver position measured by magnetic resonance imaging (MRI) with survival until discharge in fetuses with isolated congenital diaphragmatic hernia (CDH). Method Systematic searches of MEDLINE and EMBASE from 1 January 1980 to 10 December 2010 were performed. Studies correlating total fetal lung volumes (TFLV, observed/expected (O/E) TFLV) and/or liver position by fetal MRI to survival in expectantly managed fetuses with CDH were included. Data on the side of the defect, position of the liver, TFLV, O/E TFLV, gestational age (GA) at MRI, GA and weight at birth were collected. Odds ratio (OR) for dichotomous data, mean differences (MD) or standardized mean differences (SMD) for continuous variables were determined using RevMan 5.0 software. Results Nineteen studies (n = 602 fetuses) were included. Survival was associated with left-sided defects (OR 2.52; p = 0.01), “liver down” (OR 0.18; p < 0.00001), a higher TFLV (MD 9.63; p < 0.00001) and O/E TFLV (SMD 0.98; p < 0.00001) as well as higher birth weight (MD 146.60; p = 0.04). GA at MRI (MD 0.70) and GA at birth (MD 0.33) were not correlated with survival. Conclusions MRI measurements of fetal lung volumes, liver position and side of the defect correlate well with neonatal survival in fetuses with isolated CDH. Copyright © 2011 John Wiley & Sons, Ltd. Supporting information may be found in the online version of this article. KEY WORDS: fetal MRI; CDH; liver position; lung volume; survival INTRODUCTION Congenital diaphragmatic hernia (CDH) occurs sporadi- cally with an incidence of 1: 2,500 live births and accounts for about 8% of all congenital anomalies (Colvin et al., 2005). About 40% of the patients have associated structural anomalies, chromosomal aberrations or various syndromes that are associated with a high mortality (Skari et al., 2000; Stege et al., 2003). However, the majority has an isolated defect, which is left sided in 85% of cases (LCDH). In those, herniation of the liver into the thorax is observed in about 50% (Jani et al., 2006a). In the more uncommon form of right-sided CDH (RCDH, 13%) liver herniation is nearly a constant finding. Despite advances in neonatal intensive care, the associated pulmonary hypoplasia and persistent pulmonary hypertension limit postnatal survival to 63-81% in isolated cases, in which liver herniation reduces chances for survival from 75% to 53% in LCDH (Table 1) (Jani et al., 2007c, 2009a; Deprest et al., 2010). Following prenatal diagnosis, ideally counselling of the parents would require prenatal documentation of prog- nosis of the individual case, both in terms of associated structural or genetic anomalies, as well as mortality and morbidity rate. In selected cases with a poorer prognosis, parents may opt for termination of pregnancy (TOP) or, where available, fetal therapy. Fetoscopic endoluminal tracheal occlusion (FETO) is a prenatal intervention that aims at triggering lung growth in order to improve postnatal survival chances and to lower neonatal morbidity (Jani et al., 2006b, 2009b). This therapy is however investigational, but fetal surgery programs cause an acute need for accurate prediction. Obstetric ultrasound assessment is the mainstay of prenatal diagnosis and management of CDH. Today *Correspondence to: Jan A. Deprest, Department of Obstetrics and Gynecology, Division Woman and Child, Fetal Medicine Unit, University Hospital Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium. E-mail: Jan.Deprest@uzleuven.be † This report has partly been presented at the 30th Annual Meeting of the Society for Maternal-Fetal Medicine (SMFM), Chicago, IL, Feb. 01-06, 2010. Copyright © 2011 John Wiley & Sons, Ltd. Received: 4 April 2011 Revised: 28 June 2011 Accepted: 29 June 2011 Published online: 14 September 2011 PRENATAL DIAGNOSIS Prenat Diagn 2011; 31: 1086–1096. Published online 14 September 2011 in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/pd.2839