Journal of Clinical and Diagnostic Research. 2022 Feb, Vol-16(2): TD01-TD02 1 1 DOI: 10.7860/JCDR/2022/52054.16023 Radiology Section Dorsal Cord Herniation with Diastematomyelia- A Rare Case Case Report CASE REPORT A 47-year-old male patient presented with complaints of low back pain on excessive walking, radiating to right lower limb since one month. He complained of aggravation of pain with activity or excessive standing which was relieved by rest. On examination, patient had features of muscle wasting in bilateral upper and lower limbs and reduction in power of bilateral upper and lower limbs, right upper limb- 3/5, left upper limb- 3/5, right lower limb- 3/5, left lower limb 3/5. Patient had exaggerated reflexes and extensor plantar reflex on examination. Complete Blood Count (CBC), Liver Function Test (LFT) and Renal Function Test (RFT) of patient were within normal limit. He had been operated 15 years ago, details and records of which were not available for present review. Magnetic Resonance Imaging (MRI) done for the patient revealed postoperative changes in cervical and lumbar spine. The cord showed diastematomyelia from Cervical (C)3 to C5 levels with kinking of cord at this level attached to the posterior dura. Posterior subarachnoid space at this level is completely effaced with no evidence of Cerebrospinal Fluid (CSF) posterior to the cord. The Time (T)2 hyperintense signal is noted within the posterior cord at this level associated with mild cord atrophy which suggested changes of myelomalacia [Table/Fig-1-3]. Hence, on basis of clinical evaluation and MRI diagnosis of postoperative dorsal spinal cord herniation and myelomalacia in the cervical spine associated with diastematomyelia was made. Presence of myelomalacia and clinical evaluation also suggested that the disease process was chronic. Patient was advised surgical treatment to prevent further neurological deterioration, but patient denied to undergo any surgical treatment, and hence is being managed conservatively till date. On follow-up, there is no further neurological deterioration and symptoms have been reduced, however no follow-up MRI spine has been done. DISCUSSION Transdural spinal cord herniation is rare and under reported caused by herniation of spinal cord through a defect in the dura. Ventral or ventro-lateral cord herniation is relatively more common and a well described entity now with over 100 cases reported so far. Dorsal or posterior spinal cord herniation is very rare. Only six cases in the cervical spine and four in the thoracic or lumbar spine have been reported so far [1]. It is nonetheless a recognised cause of myelopathy with dural defect, either acquired post surgery or post-trauma or idiopathic in cause and congenital [1]. Transdural spinal cord herniation is a rare but treatable cause of slowly progressive myelopathy. They often present in a delayed fashion. Spinal cord herniation as a result of dural defect is classified into three groups: SAAD SHAIKH 1 , SNEHA SIRIGIREDDY 2 , VISHAL WALASANGIKAR 3 , VIRAJ SHAH 4 , RAHUL NAVANI 5 Keywords: Cervical spine, Dural-defect, Myelomalacia, Transdural ABSTRACT Transdural spinal cord herniation is rare and under reported. Ventral or ventro-lateral cord herniation is relatively more common and a well described entity. Dorsal or posterior spinal cord herniation is very rare, only five cases in the cervical spine, as per our knowledge. It is nonetheless a recognised cause of myelopathy, either acquired postsurgery or post-trauma or idiopathic in cause and congenital. The authors are reporting a rare case of a 47-year-old male patient who underwent Magnetic Resonance Imaging (MRI) spine. The MRI showed cord with diastematomyelia from C3 to C5 levels with kinking of cord at this level attached to the posterior dura. Posterior subarachnoid space at this level is completely effaced with no evidence of Cerebrospinal Fluid (CSF) posterior to the cord and hence, the patient was subsequently diagnosed as postoperative dorsal spinal cord herniation and myelomalacia in the cervical spine associated with diastematomyelia. Patient is being managed conservatively till date. [Table/Fig-1]: Time (T)2 sagittal image of cervical spine, showing kinking of spinal cord with effaced posterior subarachnoid space Cerebrospinal Fluid (CSF) signal (white arrow). Postoperative changes are seen cervical spine posteriorly (red arrow). [Table/Fig-2]: Time (T)2 Axial image of cervical spine showing diastematomyelia. Posteriorly displaced hemi cords (blue arrows), effaced posterior subarachnoid space CSF signal (red arrow) and shows abnormal T2 hyperintense signal within dorsally (white arrow); [Table/Fig-3]: T2 Axial image of cervical spine (at lower level than [Table/ Fig-2]) showing diastematomyelia ( blue arrows). There is loss of CSF signal dorsal to cord (white arrow). However, no hyperintense signal was noted in the spine as was observed before.