Closed neural tube defect

Rarer types of neural tube defects are called closed NTDs. Closed NTDs occur when the spinal defect is covered by skin.

Common examples of closed NTDs are lipomyelomeningocele, lipomeningocele, and tethered cord.

see Triple neural tube defect.

Dermoid cysts are thought to occur as a developmental anomaly in which embryonic ectoderm is trapped in the closing neural tube between the 5th-6th weeks of gestation.