The goals with testing for neural tube defects are to detect and diagnose the disorders in the developing baby and/or in the newborn and to evaluate severity and complications. Very mild cases of NTDs may never be detected or may be detected later in life when testing is performed for other reasons.
Laboratory tests are generally used to screen for neural tube defects during pregnancy. They may include:
- Maternal serum screen (triple screen or quad screen) – this group of tests is performed on the mother during her second trimester to screen for a variety of problems and includes an AFP (alpha-fetoprotein) test. An increased level of AFP in the mother's blood has been associated with an increased risk of an open NTD in the baby.
- AFP and acetylcholinesterase in amniotic fluid (see Amniotic Fluid Analysis) – if the AFP is elevated in the mother's blood, AFP and acetylcholinesterase can be measured in amniotic fluid, as confirmatory tests; an evaluation of the baby's chromosomes (fetal karyotype test) may also be done on the fluid at the same time to rule out chromosomal abnormalities as a cause of abnormal AFP. These tests are followed by or performed with a fetal ultrasound.
A variety of laboratory and non-laboratory tests may be performed by a urologist after birth to help evaluate the newborn's kidney and bladder function.
Imaging tests may be used to help detect defects in the developing baby. These may include:
- Fetal ultrasound – to help diagnose NTDs prior to birth (For more on this, see RadiologyInfo.org: Obstetrical Ultrasound)
- X-ray, MRI (magnetic resonance imaging), and/or CT scan (computed tomography) – of the spine and vertebrae after birth to look for defects and deformities
- X-ray or CT scans of the head to detect excess fluid when hydrocephalus is suspected
Regular clinical examinations of both the mother and baby are performed to detect and address complications as they arise.