title: Evaluation of the lemon and banana signs in one hundred thirty fetuses with open spina bifida.
abstract: The incidence and diagnostic accuracy of the lemon and cerebellar ultrasonographic markers, as well as head size and ventriculomegaly, were evaluated in a study of 1561 patients at high risk for fetal neural tube defects. In the 130 fetuses with open spina bifida there was a relationship between gestational age and the presence of each of these markers. The lemon sign was present in 98% of fetuses at less than or equal to 24 weeks' gestation but in only 13% of those at greater than 24 weeks' gestation. Cerebellar abnormalities were present in 95% of fetuses irrespective of gestation; however, the cerebellar abnormality at less than or equal to 24 weeks' gestation was predominantly the banana sign (72%) whereas at gestations greater than 24 weeks it was cerebellar "absence" (81%). Both growth retardation and cerebral ventriculomegaly significantly worsened with gestation while the head circumference remained disproportionately small throughout gestation. On the basis of these data, a new approach is proposed for the investigation of patients at high risk for fetal open spina bifida.
authors.affiliation: Harris Birthright Research Centre for Fetal Medicine, King's College School of Medicine, Denmark Hill, London, UK.
authors.forename: M C
authors.initials: MC
authors.lastname: Van den Hof
authors.forename: K H
authors.initials: KH
authors.lastname: Nicolaides
authors.forename: J
authors.initials: J
authors.lastname: Campbell
authors.forename: S
authors.initials: S
authors.lastname: Campbell
mesh_terms: D001139:Arnold-Chiari Malformation / Q000175:diagnosis; D001921:Brain / Q000002:abnormalities; D002531:Cerebellum / Q000002:abnormalities*; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis*; D006801:Humans; D011247:Pregnancy; D011296:Prenatal Diagnosis; D012886:Skull / Q000002:abnormalities; D016136:Spina Bifida Occulta / Q000175:diagnosis*; D014463:Ultrasonography