Spinal dysraphism

1. Spinal dysraphism

2. Spinal Dysraphism refers to a variety of congenital anomalies resulting from failed fusion of dorsal spinal elements.

3. Types Spina bifida occulta : often incidental cutaneous manifestations Spina bifida aperta : Meningocele Myelomeningocele Myelocystocele lipomeningocele

4. Meningocele Meningocele is a midline mass usually occurring in the dorsal lumbar area composed of CSF meninges and skin Neural elements are absent neurologic deficit rarely present

5. 1-2/1000 1/3 have neurological deficits Surgical repair with water-tight dural closure

6. Meningomyelocele Myelomeningocele is another defect, almost always associated with neurological deficit. The herniated mass arises midline usually in the thoracolumbar region. It contains CSF meninges and neural tissue .

7. 1-2/1000 live birth Failure of complete closure of caudal neural tube 85% occur in lumbar region Associated conditions include Chiari malformation, club foot, hydrocephalus, and various cerebral and cerebellar malformations

8. Myelomeningocele is subclassified into spina bifida cystica and aperta depending on whether the contents of the mass communicate with the environment.

9. Myelocystocele refers to a terminal swelling of the neural axis probably secondary to hydromyelia in utero . The expanding mass contains dilated cord as well as meninges CSF and fatty/fibrous tissue that herniates midline through a spina bifida defect. This results in a tethered cord syndrome.

10. Extrophy of the bladder is a common associated defect. Sacrococcygeal teratoma should be considered in the differential diagnosis.

11. Lipomeningocele refers to the fatty contents of a spina bifida lesion. These may be intradural , extradural , or both. Present with back mass, bladder problems, paralysis Cutaneous stigmata Symptoms are due to tethered cord and cord compression from fatty mass Treatment is surgical decompression

12. Anterior Meningocele is an abnormal communication between the spinal subarachnoid space and a pelvic (or rarely thoracic) mass via a channel in the anterior vertebral column

13. Radiological features Antenatal US Plain film findings structural vertebral anomalies such as hemivertebra , butterfly vertebra, or incomplete fusion of posterior elements; it does not allow imaging of the spinal cord. CT ,MR

14. Antenatal ultrasonogram shows a lumbar meningocele.

15. Antenatal ultrasonogram shows a lemon sign and a banana sign.

16. Transverse cranial sonogram of a 20-week-old fetus with spina bifida. Image obtained at the level of the ventricles demonstrates the lemon like configuration of the fetal skull due to biconcavity (arrows) of the frontal bones.

17. Defects of laminae of lower cervical spine

18. Plain radiograph of same pt showing spina bi fida occulta of s1

19. Films of the spine demonstrate spina bifida involving L2 - S1.

20. Plain anteroposterior (AP) lumbar spinal radiograph in a 7-year-old patient shows a defect within the laminae of L4-5 and S1. Note the diastematomyelia .

21. Axial CT scans through the lumbosacral junction shows absence of the posterior spinal elements at L5-S1. Note sclerosis of the laminae and the wide spinal canal.

22. When spinal malformations are suspected, investigation of the spinal canal and its contents are best performed by MRI

23. T2-weighted sagittal MRIs of the sacrum show an anterior sacral meningocele

24. Sagittal MRIs of the lumbar spine show diastematomyelia . Note the congenital fusion of L1 and L2

25. Myelograms in a 5-year-old patient show the dorsal region of the spine and an anterior thoracic meningocele . Note the gross dorsal kyphosis

26. Myelograms in a 4-year-old patient show the lumbosacral region; a long, tethered cord; and diastematomyelia .

27. Unfused arch of C1 at CT

28. T1w image,showing ventriculomegaly

29. Banan Sign: Abnormal shape of cerebelum from compression in spina bifida and other neural tube defects

30. Tethered Cord Syndrome

31. spine MR of T1-weighted ( A ) and T2-weighted images ( B ) shows tethered cornus medullaris to the level of sacrum and two isolated lipomyelomeningoceles , a transitional type from L3 to L5 (arrows), and a terminal type below S1 (arrow heads)

32. Thank you