Anencephaly and spina bifida constitute the anomaly group
called "NEURAL TUBE DEFECT." Neural tube defects occur at a rate of
1-2 per 1000 births. In order to prevent these anomalies, each pregnant woman
should use a vitamin called 0.4 mg folic acid daily before the pregnancy and
until the 3rd month of pregnancy. The frequency of neural tube defects
decreases with the use of folic acid.
Spina
Bifida: It is the condition that the spinal cord and surrounding
membranes hernia out due to the problem in the development of spinal bones and
additional tissues, which ensures the protection of the spinal nerve tissue in
the back during embryological development. There is an opening in the bones of
the spine and the skin tissues on it, and the spinal cord herniates out of this
opening.
It can occur in different ways depending on the degree of
congenital defect.
Closed
spina bifida: Only the spine is open, and the top of the opening is
covered with soft tissues and skin under the skin, there is no hernia outside
the body. Due to the protective effect of the skin on the defect, there is no
risk of infection and generally does not cause any problems in infants.
Pigmentation, depression and subcutaneous lipoma can be found on the skin in
the region of the defect.
Open spina
bifida: Here, the spine, subcutaneous tissues and skin on the spinal
cord are completely open and the spinal cord and spinal cord herniated from
this opening. It is recommended by cesarean to prevent birth nerve tissues from
being traumatized. The opening may be covered with a thin meningeal membrane.
This is called meningocele. If nerve tissue is also found in this meningocele
sac, it is called meningomeyelocele.
Treatment
and surgery:
Often, surgery is tried to be corrected within 1-2 days after
birth. Correction surgeries are more successful in meningocele than
meningomyelocele, and especially in meningomyelocele, sequela may remain
despite the operations. The location and size of the opening affects the
outcome of the baby. The mortality rate is high and almost half live less than
7 years. In most of the people, problems such as paralysis and urinary
incontinence and seizures are observed. If hydrocephalus is also present,
mental development may fall behind. Shunt surgery may be required in the
presence of hydrocephalus.
Diagnosis:
As with anencephaly, MS-AFP levels increase in maternal blood
in open spina bifida. This increase is not observed in closed spina bifida.
MS-AFP can be looked at alone in 16-20 weeks, or since the triple or quad test
includes MS-AFP, it is evaluated with these tests. Increase in MS-AFP level and
ultrasound are very useful tests in diagnosis. Despite high MS-AFP levels, if
spin bifida is not observed in ultrasonography, it is tried to be diagnosed by
looking at the levels of MS-AFP and Acetylcholinesterase (and chromosome
analysis can be studied) in amniotic fluid taken by amniocentesis. Closed spina
bifida is generally not visible on ultrasound, while open spina bifida is
usually in the 3rd-4th. can be seen on ultrasound after the month.
ADDITIONAL
INFORMATION:
- In a mother who has a baby with a neural tube defect, the
risk of recurrence in her pregnancy is about 3-4%. This risk decreases to 1%
when folic acid is used.
- Frequency order of neural tube defects: Spina bifida,
anencephaly, encephalocele
- The closure of the neural tube in the embryonic period is
completed on the 28th day after fertilization.
- Chromosomal anomalies with a high risk of neural tube
defects: trisomy 13, trisomy 18
- Syndromes associated with neural tube defect:
Meckel-Grrubel syndrome (encephalocele), Joubert syndrome, Jarcho-Levin
syndrome, Roberts syndrome, HARDE (Hydrocephalus, pain, retinal dysplasia,
encephalocele)
- If drugs such as valproic acid, carbamezapine, kumadin,
efavirens, thalidomide are used during pregnancy, it may cause neural tube
defect.
- Exposure to hyperthermia during pregnancy can cause
anencephaly.
- The risk of neural tube defects increases in pregnancies
with pregestational diabetes.
-PYELECTASIS OR HYDRONEPHROSIS
-SPINA BIFIDA
-SINGLE UMBLIKAL ARTERY
-TRISOMY 18
-VENTRICULOMEGALY
-CLEFT PALATE - LIP
