PRENATAL DIAGNOSIS Prenat Diagn 2010; 30: 402–407. Published online 5 April 2010 in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/pd.2481 The use of combined ultrasound and magnetic resonance imaging in the detection of fetal anomalies Xiomara M. Santos, Ramesha Papanna,* Anthony Johnson, Darrell L. Cass, Oluyinka O. Olutoye, Kenneth J. Moise Jr, Bella Belleza-Bascon and Christopher I. Cassady Texas Baylor College of Medicine, Children’s Fetal Center, Texas Children’s Hospital,Houston, TX, USA Objective To compare the referral diagnosis based on prenatal ultrasound to diagnoses made following combined ultrasound (US) and magnetic resonance imaging (MRI) evaluation at the Texas Children’s Fetal Center (TCFC) and postnatal diagnosis. Methods We performed a retrospective review of patients referred to the TCFC between September 2001 and July 2007 with a fetal structural malformation. Data were abstracted to compare the referral diagnosis to TCFC imaging diagnoses and both were compared to postnatal diagnosis. Results Two hundred and twenty-four patients were referred who had a fetal US and MRI at TCFC. The most frequent indications were for abnormalities of the central nervous system (38%) and lung/thoracic cavity (34%), with congenital diaphragmatic hernia (CDH) the single most common referral diagnosis (n = 39; 17%). In 99 cases (42.7%) the referral diagnosis was concordant with the post-referral diagnosis, however, in 68 cases (29.3%) the post-referral diagnosis changed completely, and in 65 cases (28%) additional findings were discovered. Prenatal diagnoses following imaging at TCFC were concordant with postnatal diagnoses in 94.9% of cases. Conclusions Combined ultrasound and MRI provides additional diagnostic information or a corrected diagnosis in 57% of cases over the referral ultrasound diagnosis. Copyright  2010 John Wiley & Sons, Ltd. KEY WORDS: prenatal diagnosis; magnetic resonance imaging; MRI; ultrasound; fetal anomaly BACKGROUND The current standard approach for the evaluation of fetal anatomy is with ultrasound, an imaging modality that it is widely available, cost-effective and allows real- time examination of the fetus (Aaronson et al., 2003; Blaicher et al., 2004). After 20 years’ experience, and with advances particularly in transducer technology, many structural fetal anomalies are now readily iden- tified by ultrasonography in multiple organ systems. However, there are limitations to ultrasonography that are both technical and situational: maternal size, image resolution, fetal position and amniotic fluid restriction can all affect the ability to establish an optimal imaging diagnosis. There is a growing body of evidence indi- cating magnetic resonance imaging (MRI) as a comple- mentary imaging technique that can provide improved characterization of selective malformations, thereby fur- ther refining prognosis and ultimately perinatal outcome (Wagenvoort et al., 2000; Breysem et al., 2003). Multiple studies have tried to compare the use of ultra- sound against MRI in the diagnosis of fetal anomalies. From the published literature, it would appear that MRI may provide additional diagnostic information to that given by ultrasound in 25% to 55% of cases, which *Correspondence to: Ramesha Papanna, Texas Children’s Fetal Center, MC2-2521, 6621 Fannin Street, Houston, TX 77030, USA. E-mail: rpapanna@gmail.com in turn would impact parental counseling and/or man- agement of affected pregnancies (Levine et al., 1997; Wagenvoort et al., 2000; Breysem et al., 2003; Mat- suoka et al., 2003; Blaicher et al., 2004; Frates et al., 2004; Whitby et al., 2004; Salomon et al., 2006; Wang et al., 2006). MRI seems most consistently useful in characterizing fetal anomalies involving the central ner- vous system (Levine et al., 1997; Wagenvoort et al., 2000; Breysem et al., 2003; Wang et al., 2006). The additional benefit of MRI in the evaluation of other fetal systems remains in question. With improved image acquisition by real-time ultra- sound and the addition of 3D techniques, there is a continued need to evaluate when additional imaging, such as with MRI, will add value in the diagnosis of prenatally detected fetal anomalies. The first objective of this study was to compare diagnoses based on refer- ral prenatal ultrasound to those obtained following the combined use of ultrasound and fetal MRI at the Texas Children’s Fetal Center (TCFC) in order to understand if and where there is value added by complementary imag- ing. Our second objective was to compare our prenatal diagnoses to postnatal diagnoses. METHODS This study is a retrospective review of the medi- cal records of pregnant women referred to the TCFC between September 2001 and July 2007 for further Copyright  2010 John Wiley & Sons, Ltd. Received: 26 October 2009 Revised: 12 January 2010 Accepted: 13 January 2010 Published online: 5 April 2010