* Spina bifida with meningocele refers to a membranous sac (with very thin overlying skin) that contains meninges but the neural structures are intact and in normal position. Despite their normal positioning, meningoceles may still cause neurological pathology (ie, paralplegia).
Spina bifida manifesta (or aperta) refers to a vertebral defect with a meningeal or spinal cord abnormality (as opposed to spina bifida occulta, which does NOT involve open abnormality).
Spina bifida cystica refers to the cyst-like sac that protrudes through the vertebral arch defect.