Fetal cerebral ventriculomegaly
- Mary E Norton, MD
Mary E Norton, MD
- Professor and Vice Chair for Clinical and Translational Genetics
- David E Thorburn, MD and Kate McKee Thorburn Endowed Chair in Perinatal Medicine and Genetics
- Department of Obstetrics, Gynecology and Reproductive Sciences
- University of California, San Francisco
- Section Editors
- Charles J Lockwood, MD, MHCM
Charles J Lockwood, MD, MHCM
- Section Editor — Obstetrics
- Senior Vice President, USF Health
- Dean, Morsani College of Medicine
- Professor, Obstetrics and Gynecology
- University of South Florida
- Deborah Levine, MD
Deborah Levine, MD
- Section Editor — Imaging
- Professor of Radiology
- Director of Ob/Gyn Ultrasound
- Department of Radiology
- Beth Israel Deaconess Medical Center
Fetal cerebral ventriculomegaly is a relatively common finding on second trimester obstetrical ultrasound examination. It is clinically important because it can be caused by a variety of disorders that result in neurological, motor, and/or cognitive impairment. Many cases are associated with other abnormal findings, but in some fetuses, ventriculomegaly is the only abnormality . This topic will discuss the prenatal diagnosis and clinical significance of ventriculomegaly and options for management of affected pregnancies.
DEFINITION AND NOMENCLATURE
The atrium of the lateral ventricle is the portion where the body, posterior horn, and temporal (inferior) horn converge. Atrial diameter remains stable between 15 and 40 weeks of gestation [2,3]. Ventriculomegaly is defined as an atrial diameter ≥10 mm, which is 2.5 to 4 standard deviations above the mean depending on the study [2-4]. Ventriculomegaly is generally considered mild if the atrial diameter is between 10 and 15 mm and severe if >15 mm, although some authors use the categories of mild (10 to 12 mm), moderate (13 to 15 mm), and severe (≥16 mm) .
Ventriculomegaly is "isolated" when the fetus has no other anomalies, except those that are a direct result of the ventricular enlargement. Many cases that appear isolated prenatally are ultimately found to have other abnormalities, particularly when ventriculomegaly exceeds 15 mm [5-8]. These abnormalities include Chiari malformations, neural tube defects, Dandy Walker malformations, agenesis of the corpus callosum, and genetic syndromes.
Hydrocephalus is the correct term for pathologic dilatation of the brain's ventricular system from increased pressure, usually due to obstruction. Ventriculomegaly is the appropriate term when dilatation is due to other causes, such as brain dysgenesis or atrophy. Because ventricular pressure cannot be measured prenatally, the two terms are sometimes used synonymously when applied to the fetus. Most commonly, the term "ventriculomegaly" is used when the ventricles are mildly enlarged, and "hydrocephalus" is used when they measure >15 mm.
Ventriculomegaly may or may not be accompanied by macrocephaly (ie, head circumference greater than two standard deviations above the mean).
- Griffiths PD, Reeves MJ, Morris JE, et al. A prospective study of fetuses with isolated ventriculomegaly investigated by antenatal sonography and in utero MR imaging. AJNR Am J Neuroradiol 2010; 31:106.
- Cardoza JD, Goldstein RB, Filly RA. Exclusion of fetal ventriculomegaly with a single measurement: the width of the lateral ventricular atrium. Radiology 1988; 169:711.
- Pilu G, Reece EA, Goldstein I, et al. Sonographic evaluation of the normal developmental anatomy of the fetal cerebral ventricles: II. The atria. Obstet Gynecol 1989; 73:250.
- Farrell TA, Hertzberg BS, Kliewer MA, et al. Fetal lateral ventricles: reassessment of normal values for atrial diameter at US. Radiology 1994; 193:409.
- Davis GH. Fetal hydrocephalus. Clin Perinatol 2003; 30:531.
- Menkes JH, Sarnat HB. Neuroembryology, Genetic Programming, and Malformations. In: Child Neurology, 6th ed, Menkes JH, Sarnat HB (Eds), Lippincott Williams and Wilkins, Philadelphia 2000. p.354.
- Partington MD. Congenital hydrocephalus. Neurosurg Clin N Am 2001; 12:737.
- Hannon T, Tennant PW, Rankin J, Robson SC. Epidemiology, natural history, progression, and postnatal outcome of severe fetal ventriculomegaly. Obstet Gynecol 2012; 120:1345.
- Alagappan R, Browning PD, Laorr A, McGahan JP. Distal lateral ventricular atrium: reevaluation of normal range. Radiology 1994; 193:405.
- Achiron R, Schimmel M, Achiron A, Mashiach S. Fetal mild idiopathic lateral ventriculomegaly: is there a correlation with fetal trisomy? Ultrasound Obstet Gynecol 1993; 3:89.
- Melchiorre K, Bhide A, Gika AD, et al. Counseling in isolated mild fetal ventriculomegaly. Ultrasound Obstet Gynecol 2009; 34:212.
- Chasen ST, Chervenak FA, McCullough LB. The role of cephalocentesis in modern obstetrics. Am J Obstet Gynecol 2001; 185:734.
- Váradi V, Tóth Z, Török O, Papp Z. Heterogeneity and recurrence risk for congenital hydrocephalus (ventriculomegaly): a prospective study. Am J Med Genet 1988; 29:305.
- Levine D, Feldman HA, Tannus JF, et al. Frequency and cause of disagreements in diagnoses for fetuses referred for ventriculomegaly. Radiology 2008; 247:516.
- Benacerraf BR, Shipp TD, Bromley B, Levine D. What does magnetic resonance imaging add to the prenatal sonographic diagnosis of ventriculomegaly? J Ultrasound Med 2007; 26:1513.
- Cardoza JD, Filly RA, Podrasky AE. The dangling choroid plexus: a sonographic observation of value in excluding ventriculomegaly. AJR Am J Roentgenol 1988; 151:767.
- Pretorius DH, Drose JA, Manco-Johnson ML. Fetal lateral ventricular ratio determination during the second trimester. J Ultrasound Med 1986; 5:121.
- Pilu G, De Palma L, Romero R, et al. The fetal subarachnoid cisterns: an ultrasound study with report of a case of congenital communicating hydrocephalus. J Ultrasound Med 1986; 5:365.
- Hilpert PL, Hall BE, Kurtz AB. The atria of the fetal lateral ventricles: a sonographic study of normal atrial size and choroid plexus volume. AJR Am J Roentgenol 1995; 164:731.
- Achiron R, Yagel S, Rotstein Z, et al. Cerebral lateral ventricular asymmetry: is this a normal ultrasonographic finding in the fetal brain? Obstet Gynecol 1997; 89:233.
- Senat MV, Bernard JP, Schwärzler P, et al. Prenatal diagnosis and follow-up of 14 cases of unilateral ventriculomegaly. Ultrasound Obstet Gynecol 1999; 14:327.
- Sadan S, Malinger G, Schweiger A, et al. Neuropsychological outcome of children with asymmetric ventricles or unilateral mild ventriculomegaly identified in utero. BJOG 2007; 114:596.
- Durfee SM, Kim FM, Benson CB. Postnatal outcome of fetuses with the prenatal diagnosis of asymmetric hydrocephalus. J Ultrasound Med 2001; 20:263.
- Kinzler WL, Smulian JC, McLean DA, et al. Outcome of prenatally diagnosed mild unilateral cerebral ventriculomegaly. J Ultrasound Med 2001; 20:257.
- Pilu G, Falco P, Perolo A, Visentin A. Ultrasound evaluation of the fetal eural axis. In: Ultrasonography in Obstetrics and Gynecology, Callen PE (Ed), W.B. Saunders Co., Philadelphia 2000. p.279.
- Fong K, Chong K, Toi A, et al. Fetal ventriculomegaly secondary to isolated large choroid plexus cysts: prenatal findings and postnatal outcome. Prenat Diagn 2011; 31:395.
- Gaglioti P, Danelon D, Bontempo S, et al. Fetal cerebral ventriculomegaly: outcome in 176 cases. Ultrasound Obstet Gynecol 2005; 25:372.
- Gaglioti P, Oberto M, Todros T. The significance of fetal ventriculomegaly: etiology, short- and long-term outcomes. Prenat Diagn 2009; 29:381.
- Sethna F, Tennant PW, Rankin J, C Robson S. Prevalence, natural history, and clinical outcome of mild to moderate ventriculomegaly. Obstet Gynecol 2011; 117:867.
- Jamieson DJ, Kourtis AP, Bell M, Rasmussen SA. Lymphocytic choriomeningitis virus: an emerging obstetric pathogen? Am J Obstet Gynecol 2006; 194:1532.
- Bonthius DJ, Wright R, Tseng B, et al. Congenital lymphocytic choriomeningitis virus infection: spectrum of disease. Ann Neurol 2007; 62:347.
- Malinger G, Lev D, Zahalka N, et al. Fetal cytomegalovirus infection of the brain: the spectrum of sonographic findings. AJNR Am J Neuroradiol 2003; 24:28.
- Chow KC, Lee CC, Lin TY, et al. Congenital enterovirus 71 infection: a case study with virology and immunohistochemistry. Clin Infect Dis 2000; 31:509.
- Seidman DS, Nass D, Mendelson E, et al. Prenatal ultrasonographic diagnosis of fetal hydrocephalus due to infection with parainfluenza virus type 3. Ultrasound Obstet Gynecol 1996; 7:52.
- Katz VL, McCoy MC, Kuller JA, Hansen WF. An association between fetal parvovirus B19 infection and fetal anomalies: a report of two cases. Am J Perinatol 1996; 13:43.
- Sarnat HB. Ependymal reactions to injury. A review. J Neuropathol Exp Neurol 1995; 54:1.
- Pagani G, Thilaganathan B, Prefumo F. Neurodevelopmental outcome in isolated mild fetal ventriculomegaly: systematic review and meta-analysis. Ultrasound Obstet Gynecol 2014; 44:254.
- Donnelly JC, Platt LD, Rebarber A, et al. Association of copy number variants with specific ultrasonographically detected fetal anomalies. Obstet Gynecol 2014; 124:83.
- American College of Obstetricians and Gynecologists Committee on Genetics. Committee Opinion No. 581: the use of chromosomal microarray analysis in prenatal diagnosis. Obstet Gynecol 2013; 122:1374.
- Pasquini L, Masini G, Gaini C, et al. The utility of infection screening in isolated mild ventriculomegaly: an observational retrospective study on 141 fetuses. Prenat Diagn 2014; 34:1295.
- Devaseelan P, Cardwell C, Bell B, Ong S. Prognosis of isolated mild to moderate fetal cerebral ventriculomegaly: a systematic review. J Perinat Med 2010; 38:401.
- Rossi AC, Prefumo F. Additional value of fetal magnetic resonance imaging in the prenatal diagnosis of central nervous system anomalies: a systematic review of the literature. Ultrasound Obstet Gynecol 2014; 44:388.
- Parazzini C, Righini A, Doneda C, et al. Is fetal magnetic resonance imaging indicated when ultrasound isolated mild ventriculomegaly is present in pregnancies with no risk factors? Prenat Diagn 2012; 32:752.
- Morris JE, Rickard S, Paley MN, et al. The value of in-utero magnetic resonance imaging in ultrasound diagnosed foetal isolated cerebral ventriculomegaly. Clin Radiol 2007; 62:140.
- Salomon LJ, Ouahba J, Delezoide AL, et al. Third-trimester fetal MRI in isolated 10- to 12-mm ventriculomegaly: is it worth it? BJOG 2006; 113:942.
- Levine D, Kazan-Tannus JF, Metha TS, et al. OC15: Concordance of prenatal ultrasound and MR diagnoses in fetuses referred for ventriculomegaly. Ultrasound Obstet Gynecol 2007; 30:371.
- Valsky DV, Ben-Sira L, Porat S, et al. The role of magnetic resonance imaging in the evaluation of isolated mild ventriculomegaly. J Ultrasound Med 2004; 23:519.
- Baffero GM, Crovetto F, Fabietti I, et al. Prenatal ultrasound predictors of postnatal major cerebral abnormalities in fetuses with apparently isolated mild ventriculomegaly. Prenat Diagn 2015; 35:783.
- Graham E, Duhl A, Ural S, et al. The degree of antenatal ventriculomegaly is related to pediatric neurological morbidity. J Matern Fetal Med 2001; 10:258.
- Manning FA, Harrison MR, Rodeck C. Catheter shunts for fetal hydronephrosis and hydrocephalus. Report of the International Fetal Surgery Registry. N Engl J Med 1986; 315:336.
- von Koch CS, Gupta N, Sutton LN, Sun PP. In utero surgery for hydrocephalus. Childs Nerv Syst 2003; 19:574.
- Beeghly M, Ware J, Soul J, et al. Neurodevelopmental outcome of fetuses referred for ventriculomegaly. Ultrasound Obstet Gynecol 2010; 35:405.
- Futagi Y, Suzuki Y, Toribe Y, Morimoto K. Neurodevelopmental outcome in children with fetal hydrocephalus. Pediatr Neurol 2002; 27:111.
- Breeze AC, Alexander PM, Murdoch EM, et al. Obstetric and neonatal outcomes in severe fetal ventriculomegaly. Prenat Diagn 2007; 27:124.
- Ball JD, Abuhamad AZ, Mason JL, et al. Clinical outcomes of mild isolated cerebral ventriculomegaly in the presence of other neurodevelopmental risk factors. J Ultrasound Med 2013; 32:1933.
- Kutuk MS, Ozgun MT, Uludag S, et al. Postnatal outcome of isolated, nonprogressive, mild borderline fetal ventriculomegaly. Childs Nerv Syst 2013; 29:803.
- Lyall AE, Woolson S, Wolfe HM, et al. Prenatal isolated mild ventriculomegaly is associated with persistent ventricle enlargement at ages 1 and 2. Early Hum Dev 2012; 88:691.
- Hammond C, Chasen S. Dilation and evacuation. In: Management of Unintended and Abnormal Pregnancy, Paul M (Ed), Wiley Blackwell, West Sussex, UK 2009. p.173.
- Jouet M, Kenwrick S. Gene analysis of L1 neural cell adhesion molecule in prenatal diagnosis of hydrocephalus. Lancet 1995; 345:161.
- DEFINITION AND NOMENCLATURE
- PRENATAL DIAGNOSIS
- Atrial assessment
- Differential diagnosis
- OBSTETRICAL ISSUES
- Initial work-up
- - Comprehensive sonographic evaluation
- - Review of medical history
- - Amniocentesis
- - Evaluation for infection
- - Magnetic resonance imaging
- Delivery management
- RECURRENCE RISK AND GENETIC COUNSELING
- SUMMARY AND RECOMMENDATIONS