6 - NEURAL TUBE DEFECTS

Neural Tube

is a hollow, tube-like structure that develops during early stages of pregnancy when the neural groove fuse between day 17 and 30 after conception.

It is the basis for the development of the entire CNS

day 17 and 30 after conception.

Neural Tube is a hollow, tube-like structure that develops during early stages of pregnancy when the neural groove fuse between ______________-

NEURAL TUBE DEFECT

are birth defects affecting brain and spinal cord development due to the failure of neural tube closure during early pregnancy

ANTERIOR NEURAL TUBE DEFECTS

POSTERIOR NEURAL TUBE DEFECTS

TYPES OF NEURAL TUBE DEFECTS

ANENCEPHALY

ENCEPHALOCELE

ANTERIOR NEURAL TUBE DEFECTS

SPINA BIFIDA

ARNOLD CHIARI II MALFORMATION

POSTERIOR NEURAL TUBE DEFECTS

ANENCEPHALY

Absence of major parts of skull along with cerebral hemispheres due to the failed closure of anterior neural tube.

Infants survive only hours to days.

Diagnosis: High AFP, Ultrasound, Polyhydramnios.

Meroanencephaly

Holoanencephaly

Craniorachischisis

There are three types of anencephaly, and all three are fatal for the fetus:

Meroanencephaly

: The brainstem and midbrain only partially develop. Some skin and skull cover the brain.

Holoanencephaly

: The brain did not develop at all. This is the most common type.

Craniorachischisis

: The brain, skull, and spine did not develop. This is the most severe type.

ENCEPHALOCELE

Brain tissue herniates through skull

The types of encephalocele identify the location of the opening in the skull:

Occipital

Parietal

Frontoethmoidal

Sphenoidal

The types of encephalocele identify the location of the opening in the skull:

Occipital:

The lower back of your baby’s head.

Parietal:

Top, nearest the back of your baby’s head.

Frontoethmoidal

(also called sincipital): Near your baby’s forehead

Sphenoidal:

Front-middle or behind your baby’s eyes and in front of their ears.

SPINA BIFIDA

Incomplete closure of spinal column

Most common along lumbar and sacral spine

SPINA BIFIDA OCCULTA

MENINGOCELE

MENINGOMYELOCELE

TYPES OF SPINA BIFIDA

SPINA BIFIDA OCCULTA

Mildest form

no spinal cord damage

MENINGOCELE

Meninges protrude; spinal cord intact.

Few nerve issues unless ruptured

MENINGOMYELOCELE

Meninges and spinal cord protrude.

Paralysis, hydrocephalus, bladder/bowel issues common

CHIARI II MALFORMATION

Brain structures extend into spinal canal.

Associated with meningomyelocele.

May cause hydrocephalus, feeding and breathing problems.

Folate deficiency

Previous pregnancy w/ NTDs

Family history of NTDs

Certain anti-seizure meds

Diabetes and obesity

Fever or high body temperature

Opioid use in early pregnancy

RISK FACTORS

Physical problems, such as paralysis and urinary and bowel control issues.

Blindness.

Deafness.

Intellectual disability.

Lack of consciousness and, in some cases, death.

General symptoms of NTDs can include:

Blood test

Ultrasound

Amniocentesis

Postnatal: MRI or CT scans

DIAGNOSIS

400–800 mcg/day

Folic acid supplementation: ___________- preconception and during pregnancy.

19–26 weeks gestation

Fetal surgery (in selected cases) for spina bifida may be offered between

24–48 hours after birth.

Surgical repair of defects (especially meningomyelocele) ideally within _____________-