ABSTRACT
The general term neural tube defect refers to all defects that occur because
of improper closure of the neural tube during development. Defects include
improper development of both the anterior neuropore (of which the most
dramatic result is anencephaly) and the posterior neuropore. Defects of the
posterior neuropore that affect the spinal elements may be classified broadly as
spinal dysraphism or spina bifida. This entity encompasses a spectrum of presen-
tations from occult lesions that involve sinus tracts and lipomas to open lesions.
In this chapter, we limit our discussion to the more commonly known open lesion
myelomeningocele.
