De Novo Formation of Idiopathic Spinal Cord Herniation.

We investigated whether idiopathic spinal cord herniation is a congenital or acquired condition and undertook a study to determine the risk of developing iSCH in patients with persistent ventral spinal CSF leaks. De novo formation of iSCH was established among all 6 patients with iSCH who had undergone prior spinal imaging for symptoms unrelated to iSCH. Among 51 patients with persistent ventral spinal CSF leaks, iSCH developed in 2 patients (probability increased from 0% at 5 years to 9.4% at 10 years). This study shows that iSCH is an acquired condition, and early treatment of ventral CSF leaks offers a unique opportunity to prevent neurologic disability.