Differential diagnosis of spinal dysraphism

• Open
  — Myelomeningocele
  — Myelocele
• Closed with subcutaneous mass
  — Lipomyelomeningocele
  — Lipomyelocele
  — Myelocystocele
  — Meningocele
• Closed without subcutaneous mass
  — Dermal sinus
  — Tethered cord
  — Spinal lipoma (intradural, intramedullary, filum terminale)
  — Split notochord syndrome (dorsal enteric fistula, neurenteric cyst)
  — Diastematomyelia
  — Caudal regression syndrome
  — Segmental spinal dysgenesis

Approach to the differential diagnosis of spinal dysraphism:

• Suspected spinal dysraphism is most commonly encountered clinically as a sacral dimple in a newborn, which should be investigated with ultrasound to look for tethered cord
• All other forms of spinal dyspraphism in a newborn whether open / overt / not skin covered lesions (spina bifida aperta = myelomeningocele and myelocele) or suspected closed / occult / skin covered lesions (spina bifida oculta = lipomyelomeningocele and lipomyelocele) should be investigated with MRI
• Suspected spinal dysraphism in an older child (spina bifida oculta = tethered cord, fatty infiltration of the filum terminale) should be investigated by MRI