How is it assessed?

Because of the complex effects of neural tube defects there are many potential investigations that can be carried out. The most common investigations include:

Prenatal diagnosis

Routine screening is undertaken for levels of alpha fetoprotein (AFP) in maternal serum between the 16th and 18th week of pregnancy. If the level of serum AFP is raised, an ultrasound scan of the baby’s head and back is performed. If following ultrasound there is a strong suspicion of a neural tube defect (NTD), amniocentesis is performed and the levels of AFP and another substance called acetylcholinesterase (ACH) in amniotic fluid are measured. Chromosomal analysis of the amniotic fluid is also undertaken to exclude chromosomal syndromes that are associated with NTDs, such as Down’s syndrome. If the levels of AFP and ACH are raised and the ultrasound scan is abnormal, it is very likely that the baby will have a NTD. The results of these tests can be used to discuss the option of a therapeutic termination of pregnancy with the parents. If the parents decide not to have a termination of pregnancy, the results can be used to plan for the future needs of the child, for example, delivery in a specialist neonatal unit with facilities for early closure of the defect.

A closed NTD may give normal enzyme levels and a normal ultrasound scan.

Mobility impairment

Formal gait analysis using video cameras and sensors linked to computers may be used to decide on the best orthopaedic treatment, including bracing and surgery.

Cognitive impairment

Because children with meningomyelocele may have a number of cognitive impairments, formal neuropsychological testing can be useful to evaluate any problems and plan treatment.

Urinary dysfunction

Beginning in early infancy, regular ultrasound of the bladder and kidneys should be undertaken to detect abnormalities. Bladder function can be assessed by performing urodynamic investigations, including cystometry in which fluid is injected into the bladder and the pressure is measured. Monitoring for urinary tract infections, which occur in at least half of children with meningomyelocele, should also be undertaken.

Neurological deterioration

Children who experience neurological deterioration should be investigated to identify any underlying cause.

Referral

It is routine for all children with spina bifida to be referred an orthopaedic surgeon, an endocrinologist and a urologist before discharge from hospital.