Spinal dysraphism can be broadly divided into two different clinicoradiological entities:

A- Open spinal dysraphism (Spina bifida aperta): 

  • Occurs when the cord and its covering communicate with the outside; no skin or tissues cover the sac e.g.:(Myelomeningocele and Myelocele)

B- Closed spinal dysraphism(Spina bifida occulta): 

  • Vertebral bone defect without herniation.
  • The spinal cord, meninges, and overlying skin remain intact.