1. CONGENITAL ABNORMALITIES OF CENTRAL NERVOUS SYSTEM

2. The incidence of malformations is higher in children with
- IUGR and multiple pregnancies
The same anomaly may occur as a result of genetic or environmental causes

3. Etiology Genetic factors Forms of microcephaly inherited as AR
Sex-linked variety of hydrocephalus
Hereditary congenital facial paralysis AD
Some anomalies have a high risk of recurrence within families
Inborn errors of metabolism
Cytogenetic abnormalities
Most important group are the trisomies( e.g Down Syndrome)
Translocations, deletions
Maternal age
Maternal infections (rubella, CMV)

4. Neural tube defects
- Most congenital anomalies of CNS and result from failure of the
neural tube to close spontaneously between the 3rd and 4th wk
in utero development

5. Anencephaly Complete absence of the cerebral hemispheres
Residue of brainstem can be identified
Females > males
Additional anomalies
- folding of ears
- cleft palate
- congenital heart defects
Most of the patients die within several days of birth
50% of cases have associated polyhydramnios
Genetic basis,low socioeconomic status,nutritional and vitamin deficiency, toxic factors

6. Encephalocele and cranial meningocele
- Protrusion of brain or meninges through a cranial defect
- Most frequent in the occipital region
- Genetic and environmental factors may be of etiologic importance
- Increased risk for hydrocephalus,chiari malformation and Dandy Walker Syndrome
- May be completely covered with skin
-Risk for visual problems
- microcephaly
- mental retardation
- seizures
- Cranial meningocel-generally good prognosis
- Determination of maternal serum alfa fetoprotein levels measurement
- Measurement of biparietal diameter in utero

7. SPINA BIFIDA OCCULTA
Midline defect of the vertebral bodies without protrusion of the spinal cord or meninges
Most individuals are asymptomatic and lack of neurologic signs
In some cases patches of hair
lipoma
discolaration of skin
dermal sinus can be seen in the midline of lower back

8. encephalocele

9. Neural tube defects
- Spinal meningocele, myelomeningocele and myelocele
All are associated with spina bifida
Meningocele
- Consists of herniation of both dura and arachnoid through a vertebral defect
Meningomyelocele
Consists of the above in addition to the spinal cord being herniated as well
Myelocele
Consists of all the above but the spinal cord is open and flat with CSF leaking on to the exposed surface
Hydrocephaly commonly occurs in association with all of the above

10. MENINGOCELE Most are covered with skin and no threat to the patient
Asymptomatic children with no neurological findings may have surgery delayed
Before surgical correction plain roentgenogram,USG,MRI should be planned for determining the extent neuronal tissue involvement

11. MENINGOMYELOCELE
Maternal periconceptional use of folic acid supplementation reduces the incidence of neural tube defects
Lumbosacral region accounts 75%of cases
Bowel and bladder incontinence
Flaccid paralysis of the lower extremities
Absence of DTR
Lack of response to touch and pain
High incidence of lower extremity deformitties
Surgery is often done within a day of birth

12. myelomeningocele

13. Arnold Chiari Malformation (ACM)(1)
Complex deformity of the brain and cerebellum
Type 1
ectopia of cerebellar tonsils
Type 2
the most common type in neonates and usually associated with lumbar myelomeningocele
Consists of lengthening of the vermis and tonsils of the cerebellum and their downward displacement through the foramen magnum in the spinal canal

14. Arnold Chiari Malformation (ACM)(2)
- Type 3
Consists of a cervical spinal bifida, the entire cerebellum being herniated through the foramen magnum
- Type 4
Cerebellar hypoplasia
The malformation develops early in gestation at the age of 10 weeks

15. Malformations of the cerebellum
Agenesis of the cerebellum
Very uncommon
Hypoplasia
Dandy Walker malformation
Occlusion of the foramina of Lushka and Magendie of 4th ventricle early in cerebral development
Small hypoplastic cerebellum with a greatly distended 4th ventricle
Obstructive hydrocephalus and cerebellar ataxia are the clinical presentation

16. Ectopias and heterotopias
Misplaced groups of neurons
Such as an island of gray matter in the subcortex
More common in the cerebellum than the cerebrum
Mutatons of genes directing the neurons to reach the final destination

17. Cortical heterotopia

18. Agyria-Lissencephaly
Total absence of gyri,
rare disorder giving the appereance of a 3-4mnt fetal brain,
failure to thrive,
microcephaly,
developmental delays,
seizures,
ocular anomalies

19. lisencephaly

20. Pachygyria
A few broad malformed gyri varying in size and number

21. pachygyria

22. Polymicrogyria
An increased number of gyri some of which may be abnormally small

23. polymicrogyria

24. Schizencephaly
Presence of unilateral or bilateral clefts within the cerebral hemispheres.
The borders of the cleft are surrounded by abnormal tissue
Many patients are severely mentally retarded,seizures and spastic quadriparesis

25. schizencephaly

26. Porencephaly Holoprosencephaly
Presence of cysts or cavities within brain communicating with the subarachnoid space
Microcephaly,encephalocele,mental retardation,spastic hemiparesis-quadriparesis,optic atrophy,seizures
Holoprosencephaly
Defective cleavage of prosencephalon
Facial anomalies are common
Lobar
Single ventricle+absent falx+fused basal ganglia
Semilobar
High mortality rates
Chromosomal anomalies and mutations

27. Microcephaly Small brain usually associated with a small head
Head ofcircumference that measures more than 3SD below the mean age and sex
Primary-have no other malformations
usually identified at birth
familial AD
Secondary-number of etiologic agents affects the fetus in utero or an infant during periods of rapid brain growth(in the first 2 yrs of age)
radiation,congenital inf,drugs
meningitis/encep.,malnutrition
metabolic,HIE

28. Megalencephaly
Proportionate enlargement of the whole brain, usually associated with the presence of a variable mental aberration
- Primary
- Secondary

29. Agenesis of corpus callosum
May be part of a complex malformation or be totally or partially absent in an otherwise normal brain
It develops between the 12 and 22 weeks of gestation
Expression from severe intellectual and neurologicalabnormalities to the asymptomatic and normally intelligent individual
Mental retardation, mild to moderate, epilepsy and cerebral palsy are common
Diagnosis can be confirmed with a CT or MRI

30. Corpus callosum agenesis

31. Hydrocephalus - Obstructive (noncommunicating)
Group of conditions that result from impaired circulation and absorbtion of CSF
- Obstructive (noncommunicating)
Resulting from the obstruction within the ventricular system
- Nonobstructive (communicating)
Resulting from obliteration of subarachnoid cisterns or malformation of the arachnoid villi

32. In a normal child 20ml/hr CSF is produced
from the lateral ventricules-
3rd vent(thr foramina Monro)-
4th vent(thr aquaduct of Sylvius)-
cisterns at the base of the brain(thr Luschka and Magendie foramina)
convexities of cerebral hemispheres-
Absorbtion(primarily by the arachnoid villi)

33. Accelerated rate of enlargement of the head
Anterior fontanel is wide open and bulging
Scalp veins are dilated
Eyes may deviate downward = setting sun eye sign
TREATMENT-ventriculoperitoneal shunt

34. HYDRANENCEPHALY
Cerebral hemispheres are absent or represented by membraneous sacs
Bilateral occlusion of the internal carotid arteries during early fetal development
İrritable child,seizures,spastic quadriparesis,no cognitive development

35. CRANIOSYNOSTOSIS
Premature closure of the cranial sutures
Primary-closure of one or more sutures
due to abnormalities skull
development
Secondary-failure of brain growth and expansion

36. Skull deformity-as a result of premature suture fusion
Prominent occiput
Broad forehead
Small or absent anterior fontanel

37. (SPLIT SPINAL CORD MALFORMATION)
DIASTEMATOMYELIA
(SPLIT SPINAL CORD MALFORMATION)
Diastematomyelia is a division of the spinal cord in to two halves by projection of a fibrocartilagionous or bony septum originating from the posterior vertebral body
It represent a disorder of neural tube fusion
The defect involves the lumbar vertebrae (L1-L3) in 50% of cases
Abnormalities of vertebral bodies
Fusion defects
Hypoplasia
Kyphoscoliosis
Spina bifida
Myelomenıngocele

38. CLINICAL MANIFESTATIONS
Dmm
CLINICAL MANIFESTATIONS
A midline abnormality of the skin in the lumbosacral region
In some cases the patients are asymplomatic
Unilateral foot abnormalities
Claw toes
Atrophy of gastrocnemius
Bilateral weakness and atrophy in lower extremities
Urinary ıncontinence
Low back pain
Loss of pain and temperature sensation

39. SYRINGOMYELIA
A cystic cavity within the spinal cord that may communicate with CSF pathways or remain localized and noncommunicating
Communicating syringomyelia is frequently associated with the chiari type I malformation →constriction of the central canal at the level of foramen magnum during enbriogenesis
Non communicating syringomyelia is associated with cord tumors, vascular accidents, trauma and arachnoiditis

40. Sm
Syringabulbia exists when the cystic cavity extends ınto the medulla
Syringomyelia rarely produces symptoms during childhood because of slow evolution

41. Sm
Asymmetric loss of pain and temperature sensation in the upper extremities
Muscle wasting of the hands
Absent deep tendon reflexes
Rapidly progressive scoliosis
Trophic ulcers associated with vasomotor disturbances of the hands and arms loss of appreciation of pain

42. TETHERED CORD (TC)
During fetal development the spinal cord occupies the entire length of the vertebral column
Due to differential growth the conus medullaris in a child ultimately assumes a position at the level of L1
Normal regression of the distal embrionic spinal cord produces a slender, threadlike filum terminale that is attached to the coccyx

43. Tc
TC results when a thickened ropelike filum terminale persists and anchors the conus at the below the L2 level
Neurologic signs may develop as a result of abnormal tension of spinal cord
In addition to a tight filum, sacral agenesis, intradural lipoma, myelomeningocele and dermal sinus may be associated with the tethered spinal cord syndrome

44. CLINICAL MANIFESTATIONSTc
CLINICAL MANIFESTATIONS
In 70% of cases inspection of the back show a midline skin lesion such as lipoma, tuft of hair, dermal sinus, portwine stain or hyperpigmentation of the skin
Signs may be evident at birth or may be delayed until adulthood
Infants may have asymmetric growth in foot or leg
Cavus deformities
Muscle wasting

45. Tc
The child may be delayed in walking
Toe walking
Regression of lower extremity function

46. Tc
The lower motor neuron signs in the legs
Abnormalities in bladder function
Recurrent urinary tract infections
Bowel incontinence
Constipation
Progressive scoliosis
Diffuse pain in the lower extremities

47. Tc
Plain roentgenogram = Lumbosacral bodies may show widening of the interpedicular distance hemivertabrae malformations the anterior spinal sagments
MRI = outlines the level of the conus medullaris and the filum terminale