Myeloschisis (myelocele) a developmental defect characterized by a cleft spinal cord that results from the failure of the neural plate to fuse and form a complete neural tube. The spinal canal is directly exposed. Inevitably spina bifida is a sequel. In total myeloschisis, the spinal cord is abscent, neural tissue being present as soft red masses. Local myeloschisis is a localized defect caused by failure of closure of the neural tube. One or more vertebral segments may be defective. The defect can occur in any segment of the vertebral axis, but most offten is seen in lumbosacral section. The defects most often occurs in calves, lambs, foals, cats and especially frequently in brachycephalic breeds of dogs and is inherited as an autosomal dominant condition in Manx cats.1


  1. Jubb, Kennedy & Palmer's Pathology of Domestic Animals, Volume 1. Grant Maxie
  2. Magnetic resonance imaging in the prenatal diagnosis of neural tube defects 2013