pubmed-article:88060 | pubmed:abstractText | The ultrasonic appearance of the normal and abnormal fetal spine before 20 weeks' gestation was reviewed in 121 pregnances. A model was constructed to establish the mechanism of production in the various configurations seen. The relative roles of ultrasonography, alpha fetoprotein assay, and fetoscopy in the diagnosis of spina bifida are discussed. | lld:pubmed |