1. COMMON CONGENITAL NEUROSURGICAL DISEASES Essam Elgamal 1 428 surgery team

2. 2Outline Approach to Congenital Neurosurgical Diseases Approach to Congenital Neurosurgical Diseases Development of the Nervous System Development of the Nervous System Congenital Malformations Congenital Malformations Neural Tube Defect Neural Tube Defect Congenital Hydrocephalus Congenital Hydrocephalus Arnold Chiari Malformation Arnold Chiari Malformation Dandy-Walker Cyst Dandy-Walker Cyst Arachnoid Cyst Arachnoid Cyst Craniosynostosis Craniosynostosis Neurocutaneous Syndromes Neurocutaneous Syndromes 2

3. 3 What can go wrong with the brain? Abnormal development Abnormal development Pernatal Events Pernatal Events Abnormal functioning Abnormal functioning Abnormal programming Abnormal programming Neural Tube Defects Neural Tube Defects Neuromigrational Disorders Neuromigrational Disorders Cerebral palsy Cerebral palsy Seizures & Epilepsy Seizures & Epilepsy Hydrocephalus Hydrocephalus Neurofibromatosis Neurofibromatosis Tuberous Sclerosis Tuberous Sclerosis Sturge-Weber Syndrome Sturge-Weber Syndrome Mitochondrial Disorders Mitochondrial Disorders 3

4. 4 Development of the Nervous System 4

5. 5 Gross Development Ectoderm Ectoderm  Will form nervous system and outer skin Endoderm Endoderm  Will form skeletal system and voluntary muscle Mesoderm Mesoderm  Will form gut and digestive organs 5

6. 6 Developmental Sequence Neural plate invaginates as neural folds push up Neural plate invaginates as neural folds push up Neural folds eventually form neural groove Neural folds eventually form neural groove Cells of neural fold eventuall meet Cells of neural fold eventuall meet Form the neural tube Form the neural tube 6

7. 7 Developmental Sequence Neural tube runs anterior – posterior along embryo Neural tube runs anterior – posterior along embryo Surrounding ectoderm eventually encloses neural tube Surrounding ectoderm eventually encloses neural tube When neural tube closes off brain and spinal cord are formed When neural tube closes off brain and spinal cord are formed 7

8. 8 Human Embryo Primitive brain consists of 3 cavities that will form ventricles Primitive brain consists of 3 cavities that will form ventricles Brain’s gross features are then formed through a series of bends Brain’s gross features are then formed through a series of bends 8

9. 9 Human Embryo Developing embryo Developing embryo Goes through a series of folds or “flexures” Goes through a series of folds or “flexures” Gives rise to the compact structure of the brain Gives rise to the compact structure of the brain BrainDiencephalonMidbrain 9

10. 10 Congenital Malformations Neural Tube Defects ( the most common defect ) (Dysraphism) 10

11. 11Pathophysiology Spina bifida occulta (closed) Spina bifida occulta (closed) 5-10% of population 1/1000 in US, 2/1000 in ksa 5-10% of population 1/1000 in US, 2/1000 in ksa not clinically significant not clinically significant tuft of hair, dimple sinus or port wine stain tuft of hair, dimple sinus or port wine stain high incidence of underlying defect high incidence of underlying defect no treatment required just to cover it, U/S or MR no treatment required just to cover it, U/S or MR 11

12. 12Pathophysiology The openings at each end are termed the rostral and caudal neuropores, and close at around the 24 th and 27 th days respectively The openings at each end are termed the rostral and caudal neuropores, and close at around the 24 th and 27 th days respectively If the neural folds do not fuse at the rostral end, anencephaly results If the neural folds do not fuse at the rostral end, anencephaly results If the neural folds do not fuse at the caudal end, myeloschisis (cleft spinal cord) results (the most severe form of spina bifida) treated as an emergency case, just few hour after delivery If the neural folds do not fuse at the caudal end, myeloschisis (cleft spinal cord) results (the most severe form of spina bifida) treated as an emergency case, just few hour after delivery 12

13. 13 myeloschisis If it doesn’t get closed = myeloschisis anencephaly 13

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15. 15 Failure of vertebral arch bony growth and fusion.Failure of vertebral arch bony growth and fusion. Neurologic symptoms are usually absent, although problems may occur during growth owing to "tethering" of the spinal cord.Neurologic symptoms are usually absent, although problems may occur during growth owing to "tethering" of the spinal cord. Skin anomalies frequently overlie the defect, including a hairy patch, hemangioma, or dermal sinusSkin anomalies frequently overlie the defect, including a hairy patch, hemangioma, or dermal sinus Meninges with CSF bulge through the defect coverd by skin Same as B +Spinal cord and its nerves enter the defect Neural tissue is directly exposed 15

16. 16 Multiple factors implicated: not well understood Multiple factors implicated: not well understood  Folate deficiency (most common cause) (there is no benefit to give folic acid after 24 th -27 th day)  Radiation & chemicals  Drugs  Malnutrition  Genetic determinants (mutations in folate-responsive or folate-dependent pathways) 16

17. 17 Diagnosis Maternal Alpha Fetoprotein Maternal Alpha Fetoprotein  AFP leaks into amniotic fluid, and then into maternal blood in case of open spina bifida  Blood level taken 13-16 weeks gestation is used as a screening test; Amniocentesis Amniocentesis  at around 18 weeks, allows detection of over 99 percent of fetuses with neural tube defects Ultrasound Ultrasound MRI MRI U.S is the first way to detect neural tube defect M.R.I is the confirmatory method to detect neural tube defect 17

18. 18 Associated anomalies Assess for presence & severity of Assess for presence & severity of  Chiari Malformation  Hydrocephalus  Associated brain malformations  Extremity deformities: contractures  Congenital kyphosis and/or scoliosis  Other abnormalities (renal, bowel, bladder, cardiac) 18

19. 19 Chiari II Malformation Cerebellar tonsil Herniation plus Medulla distortion and dysplasiaCerebellar tonsil Herniation plus Medulla distortion and dysplasia Seen in >50% of children with lumbar myelomeningocoeles Seen in >50% of children with lumbar myelomeningocoeles Hydrocephalus results from aqueduct stenosis or an obstruction of outflow of CSF from 4 th ventricle secondary to herniationHydrocephalus results from aqueduct stenosis or an obstruction of outflow of CSF from 4 th ventricle secondary to herniation Symptoms of raised ICP, oropharyngeal dysfunction, cranial nerve palsies, cardiorespiratory failureSymptoms of raised ICP, oropharyngeal dysfunction, cranial nerve palsies, cardiorespiratory failure Dx by MRIDx by MRI Rx by Posterior fossa decompression & VP shuntRx by Posterior fossa decompression & VP shunt Chiari I Malformation Cerebellar herniation through foramen magnumCerebellar herniation through foramen magnum Incidental finding: headache; neck pain; oropharyngeal dysfunctionIncidental finding: headache; neck pain; oropharyngeal dysfunction Diagnosed in adulthoodDiagnosed in adulthood 19

20. 20 Further Assessment Latex Allergy (gloves) (all children with spina bifida are considered to have allergy to latex till prove otherwise ) Latex Allergy (gloves) (all children with spina bifida are considered to have allergy to latex till prove otherwise ) Seizures Seizures Nutrition: obesity or malnutrition Nutrition: obesity or malnutrition VP shunt dysfunction VP shunt dysfunction Psychosocial development Psychosocial development 20

21. 21 Clinical manifestations Sacral and Low Lumbar (L4, L5) most common site Sacral and Low Lumbar (L4, L5) most common site  Ambulate into adulthood  Ankle/Foot orthoses (device to support limb function) Mid-lumbar (L3, L4) Mid-lumbar (L3, L4)  Difficulties with ambulation into adulthood  As above plus crutches/walker  Wheelchair for distances High lumbar & Thoracic (L2 & above) High lumbar & Thoracic (L2 & above)  May be trained to ambulate in early childhood  Hip-knee-ankle orthoses  Walker or crutches but most wheelchair-bound 21

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23. 23 Encephalocele Encephalocele = A sac with a part of brain but this part Encephalocele = A sac with a part of brain but this part doesn’t work Usually occipital Usually occipital may contain occipital lobe, or cerebellum may contain occipital lobe, or cerebellum often associated with hydrocephalus often associated with hydrocephalus Immediate treatment if ruptured to prevent infection Immediate treatment if ruptured to prevent infection outcome depends upon contents outcome depends upon contents Meningeocele in skull = A sac in the skull with no brain Meningeocele in skull = A sac in the skull with no brain 23

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25. 25 Congenital Hydrocephalus 25

26. 26 Enlargement of brain ventricles (internal hydrocephalus) and/or subarachnoid spaces (external hydrocephalus), associated with increased ICP. The incidence 0.9 and 1.8/1000 live births. Definition 26

27. 27 RATIONALE CSF secretion is an active process. 70% by ventricular choroid plexuses, 30% by extrachoroid sources capillary ultrafiltrate, ependyma, metabolic water production rate of production is 0.35 ml/min or 500 ml/day. 350ml/day reabsorbed 27

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29. 29 CSF is passively absorbed by: arachnoid villi into venous dural sinuses other pathways of absorption: spine venous plexuses. perivascular and the perineural sheaths. 29

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31. 31 PATHOPHYSIOLOGY 1. CSF overproduction: hypervitaminosis A, choroid plexus tumors. 2. Obstruction to CSF flow. ventricular dilatation generates mechanical damages to the parenchyma. 3- decreased absorption by adhesion (N:B: adhesion occur in case of trauma, infection,& hemorrhage ) 4- DVT in dural veinous sinusis 31

32. 32 Clinical manifestations depends on age Infants & young children: 1. Increasing head circumference. 2. Irritability, lethargy, poor feeding, and vomiting. 3. Bulging anterior fontanelle. 4. Widened cranial sutures. 5. McEwen's cracked pot sign with cranial percussion. ( palpable separation of cranial suture, percussion of the skull evokes a 'jagged' sound ) 6. Scalp vein dilation (increased collateral venous drainage). 7. Sunset sign (forced downward deviation of the eyes, a neurologic sign almost unique with hydrocephalus). 8. Epidsodic bradycardia and apnea & HTN. Occur later in life 32

33. 33 Treatment Endoscopic third ventriculostomy CSF diversion: V-P shunt V-A shunt V-Plural shunt V-sinus shunt 33

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36. 36 Chiari malformation 36 lumbar myelomeningocoeles and may be ended up with hydrocephalus type II chiari malformation associated with lumbar myelomeningocoeles and may be ended up with hydrocephalus

37. 37 Dandy-Walker cyst Cyst in cerebellar area  no cerebellum = cerebellar agenisis 37

38. 38 Arachnoid cyst Incidentally Dx, conservative Rx 38

39. 39 Craniosynostosiss 39

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45. 45 Neurocutaneous Syndromes Tuberous Sclerosis 45

46. 46 Neurocutaneous Syndromes Neurofibromatosis Type 1 46

47. 47 Lisch nodule Café au lait spot Neufibromas 47

48. 48 Optic glioma 48

49. 49 Thank you abo-7med 49