Etiology and Prognosis of Severe Ventriculomegaly Diagnosed at Late Gestation Ätiologie und Prognose einer schweren Ventrikulomegalie bei Diagnose in der Spätschwangerschaft Authors Andrea Dall’ Asta 1, 2 , Noortje HM van Oostrum 3 , Sheikh Nigel Basheer 1, 4 , Gowrishankar Paramasivam 1 , Tullio Ghi 2 , Letizia Galli 2 , Irene AL Groenenberg 3 , Amanda Tangi 5 , Patrizia Accorsi 6 , Monica Echevarria 7 , Maria Angeles Rodríguez Perez 7 , Gerard Albaiges Baiget 7 , Federico Prefumo 5 , Tiziana Frusca 2 , Attie TJI Go 3 , Christoph C Lees 1, 8, 9 Affiliations 1 Centre for Fetal Care, Queen Charlotte’s and Chelsea Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom 2 Obstetrics and Gynaecology Unit, University of Parma, Parma, Italy 3 Department of Obstetrics, Gynaecology and Prenatal Diagnosis, Erasmus Medical Centre, Rotterdam, the Netherlands 4 Department of Paediatrics and Neonatal Medicine, Hammersmith Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom 5 Department of Obstetrics and Gynaecology, University of Brescia, Brescia, Italy 6 Department of Child Neurology and Psychiatry, ASST Spedali Civili, Brescia, Italy 7 Fetal Medicine Section, Department of Obstetrics, Gynecology and Reproductive Medicine, University Hospital Quiron Dexeus, Barcelona, Spain 8 Department of Surgery and Cancer, Imperial College London, United Kingdom 9 Department of Development and Regeneration, KU Leuven, Leuven, Belgium Key words fetal neurosonography, central nervous system, antenatal ultrasound, third-trimester scan received 11.09.2017 accepted 16.04.2018 Bibliography DOI https://doi.org/10.1055/a-0627-7173 Published online: July 5, 2018 Ultraschall in Med 2018; 39: 675–689 © Georg Thieme Verlag KG, Stuttgart · New York ISSN 0172-4614 Correspondence Dr Christoph C. Lees, MD, MRCOG Centre for Fetal Care, Queen Charlotte’s and Chelsea Hospital, Imperial College Healthcare NHS Trust, Du Cane Road, London, W12 0HS, United Kingdom christoph.lees@.nhs.net ABSTRACT Objectives We sought to assess the causes and outcomes of severe VM diagnosed de novo after 24 weeks of gestation where a mid-trimester anomaly scan was described as normal. Methods Multicenter retrospective study of five European fetal medicine centers. The inclusion criteria were normal anatomy at the mid-trimester scan, uni/bilateral finding of posterior ventricle measuring ≥ 15 mm after 24 weeks with neonatal and postnatal pediatric and/or neurological assess- ment data. Results Of 74 potentially eligible cases, 10 underwent termi- nation, the outcome was missing in 19 cases and there was 1 neonatal death. Therefore, 44 formed the study cohort with a median gestation at diagnosis of 32 + 0 weeks (25 + 6 – 40 + 5). VM was unilateral in five cases. Agenesis of the corpus callosum (ACC) and grade III/IV intraventricular hemorrhage (IVH) accounted for 14 cases each. ACC was isolated in 9 fetu- ses. Obstructive abnormalities included 5 arachnoid and 1 cavum velum interpositum cyst. Four fetuses had an associat- ed suspected or confirmed genetic condition, 2 congenital in- fections, 1 abnormal cortical development and the etiology was unknown in 3/44. Postnatal assessment at median 20 months (3 – 96) showed 22/44 (50 %) normal, 7 (16 %) mildly abnormal and 15 (34 %) severely abnormal neurodevelop- mental outcomes. Conclusion One half of babies with severe VM diagnosed after 24 weeks have normal infant outcome with ACC and IVH representing the most common causes. Etiology is the most important factor affecting the prognosis of fetuses with severe VM diagnosed at late gestation. ZUSAMMENFASSUNG Ziel Bestimmung der Ursachen und Folgen einer schweren Ventrikulomegalie (VM) mit de-novo Diagnose nach 24 Schwangerschaftswochen (SSW) bei unauffälligem Basisultra- schall im 2. Trimenon. Methoden Multizentrische retrospektive Studie in 5 europä- ischen Pränatalzentren. Die Einschlusskriterien waren eine normale Fetoanatomie beim Screening im 2. Trimenon, ein nach der 24. SSW auftretender uni-/bilateraler Befund im Hin- terhorn von > 15 mm sowie neonatale und postnatale pädia- trische und / oder neurologische Befunde. Original Article 675 Dall’ Asta A et al. Etiology and Prognosis… Ultraschall in Med 2018; 39: 675–689