RT Book, Section A1 Gomella, Tricia Lacy A1 Cunningham, M. Douglas A1 Eyal, Fabien G. A1 Tuttle, Deborah J. SR Print(0) ID 1107524663 T1 Neural Tube Defects T2 Neonatology: Management, Procedures, On-Call Problems, Diseases, and Drugs, 7e YR 2013 FD 2013 PB McGraw-Hill Education PP New York, NY SN 9780071768016 LK accesspediatrics.mhmedical.com/content.aspx?aid=1107524663 RD 2024/03/29 AB Neural tube defects (NTDs) are malformations of the developing brain and spinal cord. In normal development, the closure of the neural tube occurs over a 4- to 6-day period with completion around the 29th day postconception, often before a woman has realized that she is pregnant. Most current hypotheses consider NTDs to be defects from failure of a neural tube closure rather than the reopening of a previously closed tube. Most likely, the closure starts at several distinct sites rather than being one continuous process. The nomenclature for NTDs is not standardized and is thus often confusing. Frequently used terms are as follows: