Congenital Anomalies of Central Nervous System Prof Samiya Naeemullah Diplomate American Board Of Pediatrics FCPS,FAAP. Head Of Department Of Pediatrics Islamic International Medical college
Learning Objectives • Recognize Anomalies of Head • Hydrocephalus,Microcephaly • How do they Present clinically • Recognize anomalies of Spine • Neural Tube defects • Spina bifida • Recognize clinical manifestations
HYDROCEPHALUS • Congenital • Acquired • Excessive accumulation of cerebrospinal fluid (CSF) in the cerebral cavity . • There is either impaired absorption or increased production of CSF. • There Is obstruction to the flow of CSF and dilatation occurs distal to obstruction
Clinical features • IN INFANTS • Accelerated rate of enlargement of head • Anterior fontanel is wide and bulging • Scalp veins are dilated • The forehead is broad • Fixed downward gaze • And sunsetting of eyes
OLDER CHILDREN • Irritability,lethargy • poor appetite • vomiting,headache • A gradual change in personality and intellectual productivity • Serial measurement in head circumference shows increased velocity
EXAMINATION Cracked Pot sign • Papilledema, • Abducens nerve palsy • Pyramidal tract sign more evident in lower limbs
MACROCEPHELY • Head circumference above 98th percentile • Normal children may have large heads • Familial • Tall stature • Hydrocephalus • Subdural hematoma,Cerebral tumour, • Cerebral gigantism
MICROCEPHALY • Head circumference below 2nd centile • Abnormalities in fetal development during neuronal migration • Familial • Autosomal recessive condition with developmental delay • Congenital infection • Perinatal Asphyxia,meningitis
NEURAL TUBE DEFECTS • Failure of the neural tube to close spontaneously between 3rd & 4th week in utero development • CAUSES • Maternal Diabetes • Maternal obesity • Mutations in folate dependent or folate responsive pathways
MAJOR DEFECTS • Spina bifida occulta • Meningocele • Myelomeningocele • Encephalocele • Anancephaly • Dermal sinus • Tethered cord
SPINA BIFIDA OCCULTA • Midline defect of the vertebral bodies without protrusion of the spinal cord or meninges • Mostly asymptomatic • In the midline of the lower back(L5 S1) Patches of hair, Lipoma, Discolouration of skin Dermal sinus • ,
MENINGOCELE • Meninges herniate through a defect in posterior vetebral arches • A fluctuating midline mass that transilluminates occurs along the vetebral column in lower back well covered with skin
MYELOMENINGOCELE • Most severe form of dysraphism • 1 in 4000 live births • Lumbosacral in 75% of cases. • Dysfunction of many organs and structures including skin, skeleton, gastrointestinal and genitourinary tract.
NEUROLOGIC DEFICIT • Depends on the location of defect • Low sacral • Bladder and Bowel incontinence • Mid Lumber Region • Flaccid paralysis of lower limbs • Absent deep tendon reflexes • Lack of response to touch and pain • High incidence of lower extremity deformities.
ANENCEPHALY • A defect in the calvarium meninges and scalp • Rudimentary brain • failure of closure of rostral neuropore (opening of the anterior neural tube.) • The cerebral hemispheres and cerebellum are absent and a residue of brainstem present
PREVENTION • Folic Acid Tablets • 4 mg daily one month before conception