Cerebral palsy is due to damage occurring to the developing brain.This damage
can occur during pregnancy, delivery, the first month of life, or less commonly
in early childhood. Structural problems in the brain are seen in 80% of cases,
most commonly within the white matter. More than three quarters of cases are
believed to result from issues that occur during pregnancy.
While in certain cases there is no identifiable cause, typical causes include
problems in intrauterine development (e.g. exposure to radiation, infection,
fetal growth restriction), hypoxia of the brain (thrombotic events, placental
conditions), birth trauma during labor and delivery, and complications around
birth or during childhood.
Preterm birth
Between 40% and 50% of all children who develop cerebral palsy were born
prematurely. Most of these cases (75-90%) are believed to be due to issues that
occur around the time of birth, often just after birth. Multiple-birth infants
are also more likely than single-birth infants to have CP. They are also more
likely to be born with a low birth weight.
In those who are born with a weight between 1 kg and 1.5 kg CP occurs in 6%.
Among those born before 28 weeks of gestation it occurs in 11%. Genetic factors
are believed to play an important role in prematurity and cerebral palsy
generally. While in those who are born between 34 and 37 weeks the risk is 0.4%
(three times normal).
Term infants
In babies that are born at term risk factors include: problems with the
placenta, birth defects, low birthweight, breathing meconium into the lungs, a
delivery requiring either the use of instruments or an emergency Caesarean
section, birth asphyxia, seizures just after birth, respiratory distress
syndrome, low blood sugar, and infections in the baby.
As of 2013 it was unclear how much of a role birth asphyxia plays as a cause.
It is believed, however, that only a small number of cases are caused by lack of
oxygen during birth. It is unclear if the size of the placenta plays a role.As
of 2015 it is evident that in advantaged countries, most cases of cerebral palsy
in term or near-term neonates have explanations other than asphyxia.
Genetics
About 2% of all CP cases are inherited, with glutamate decarboxylase-1 being
one of the possible enzymes involved. Most inherited cases are autosomal
recessive, meaning both parents must be carriers for the disorder in order to
have a child with the disorder.
Early childhood
After birth, other causes include toxins, severe jaundice, lead poisoning,
physical brain injury, stroke,[26] shaken baby syndrome, incidents involving
hypoxia to the brain (such as near drowning), and encephalitis or meningitis.
The three most common causes of asphyxia in the young child are: choking on
foreign objects such as toys and pieces of food, poisoning, and near
drowning.
No comments:
Post a Comment