Download - Disorders of Neural Tube Closure
![Page 1: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/1.jpg)
Disorders of Neural Tube Closure
Dr Malith Kumarasinghe (MBBS)
![Page 2: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/2.jpg)
Review of Neuroembryology• Dorsal induction• Primary neurolation: 3-4 wks
gestation Brain and upper spine• Secondary neurolation: 4-5 wks
gestation Distal spine
![Page 3: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/3.jpg)
Disorders of neural tube closure• Chiari I-IV• Encephaloceles• Anencephaly• Corpus Callosum Agenesis• Spinal Dysraphism (Spina bifida)• - Menigoceles• - Myelomeningoceles• Tethered chord
![Page 4: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/4.jpg)
Enephaloceles• Anatomy• Failure of the anterior neural tube to
close due to genetic, infection, or toxic reasons.
• 1/1000• Distorted parts of the (covered) brain
protruding extracalvarially
![Page 5: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/5.jpg)
EncephaloceleAnatomyOccipital 90%Parietal 10%TranssphenoidalFrontoethmoidal Nasal
![Page 6: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/6.jpg)
Encephaloceles• Parietal
encephalocele
• Frontoethmoidal encephalocele
![Page 7: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/7.jpg)
Encephaloceles• ClinicalDepends on involvement
• TreatmentSurgical excision of sac with water-
tight dural closure
![Page 8: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/8.jpg)
Anencephaly• 1/1000 • Anencephaly is a defect in the
closure of the neural tube during fetal development.
• Large defect of the calvarium, meninges, and scalp.
• Incompatible with life.
![Page 9: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/9.jpg)
Anencephaly
![Page 10: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/10.jpg)
Corpus callosum• Location?• Functions?
![Page 11: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/11.jpg)
![Page 12: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/12.jpg)
![Page 13: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/13.jpg)
Lateralization of Function• Lateralization of function refers to
the idea that each hemisphere of the brain is specialized for different functions.
• Each hemispheres controls the contralateral (opposite) side of the body.– Example: skin receptors and muscles
mainly on the right side of the body.– Each hemisphere sees the opposite
side of the world.
![Page 14: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/14.jpg)
Lateralization of Function• The left and right hemisphere
exchange information primarily through a set of axons called the corpus callosum.
• Other areas that exchange information include:– The anterior commissure.– The hippocampal commissure.– A few other small commissures.
• Information crosses to the other hemisphere with only a brief delay.
![Page 15: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/15.jpg)
Fig. 14-2, p. 418
![Page 16: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/16.jpg)
Corpus Callosum Agenesis• Expansion of third ventricle• May present with HCP, seizures• May be incidental finding without any
clinical significance
![Page 17: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/17.jpg)
Spinal Dysraphism (spina bifida)• Spina bifida occulta: 20-30% in North
Americans, often incidental, cutaneous manifestations
• Spina bifida aperta:• Meningocele • Myelomeningocele
![Page 18: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/18.jpg)
Spinal Dysraphism• Spina bifida occulta
![Page 19: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/19.jpg)
Spinal Dysraphism• Meningocele
![Page 20: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/20.jpg)
Spinal Dysraphism• Myelomeningocele
![Page 21: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/21.jpg)
Meningocele• 1-2/1000• 1/3 have neurological deficits• Surgical repair with water-tight dural
closure
![Page 22: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/22.jpg)
Meningomyelocele• 1-2/1000 live birth• Failure of complete
closure of caudal neural tube
• 85% occur in lumbar region
![Page 23: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/23.jpg)
Meningomyelocele
![Page 24: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/24.jpg)
Meningomyelocele
![Page 25: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/25.jpg)
Myelomeningocele• Clinical• Mild to complete paralysis• Ruptured vs unruptured• Urinary incontinence• Skeletal abnormalities
![Page 26: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/26.jpg)
Myelomeningocele• Treatment• If open, Gent and Naf IV• Prone, bottom up• Telfa with wet gauze over lesion• Surgical closure within 36hrs• Shunt if overt HCP• Urologic and Orthopaedic
consultation
![Page 27: Disorders of Neural Tube Closure](https://reader035.vdocuments.site/reader035/viewer/2022081514/5681636a550346895dd444ba/html5/thumbnails/27.jpg)
Lipomyelomeningocele• Present with back mass, bladder
problems, paralysis• Cutaneous stigmata• Treatment is surgical decompression