Microcephaly

Microcephaly (my-kroh-SEF-uh-lee) is a rare neurological condition in which an infant's head is significantly smaller than the heads of other children of the same age and gender. Microcephaly, which is sometimes detected at birth, is usually caused by the brain developing abnormally in the womb or failing to grow as it should after birth.

Causes:

Microcephaly is typically caused by abnormal brain development, which can occur in the womb (congenital) or during childhood. Microcephaly may be inherited. Other possible causes include:

• Craniosynostosis: The preterm fusion of the joints (sutures) that form an infant's skull prevents the brain from growing. Typically, treating craniosynostosis (kray-nee-o-sin-os-TOE-sis) requires surgery to separate the fused bones. If there are no underlying brain problems, this surgery gives the brain enough room to grow and develop.
• Anomalies in the chromosomes. Microcephaly can be caused by Down syndrome and other conditions.
• Reduced oxygen supply to the fetal brain (cerebral anoxia).
• Certain pregnancy or delivery complications can impair oxygen delivery to the fetal brain.
• Fetal infection during pregnancy.
• Toxoplasmosis, cytomegalovirus, German measles (rubella), and chickenpox are among them (varicella).
• Prenatal exposure to drugs, alcohol, or certain toxic chemicals.
• Any of these put your baby's brain at risk for abnormalities.
• Malnutrition is severe.
• Inadequate nutrition during pregnancy can have an impact on your baby's development.
• The mother has uncontrolled phenylketonuria (fen-ul-kee-toe-NU-ree-uh), also known as PKU. PKU is a congenital disorder that impairs the body's ability to break down the amino acid phenylalanine.

Signs and symptoms:

• A significantly smaller head size than other children of the same age and gender. The distance around the top of a child's head is used to calculate the head size (circumference). The measurement is compared in percentiles to other children's measurements using standardized growth charts. Some children simply have small heads, with measurements that fall into the first percentile. Head size in children with microcephaly is significantly below average, possibly even below the first percentile for your baby's age and gender.
• A child with severe microcephaly may also have a slanted forehead.

Diagnosis:

• Perform a thorough prenatal, birth, and family history, as well as a physical exam. Measure your child's head circumference, compare it to a growth chart, and re-measure and plot the growth at subsequent visits.
• Parents' head sizes can also be measured to see if small heads run in the family.
• A head CT scan or MRI, as well as blood tests, may be used to help determine the underlying cause of the delay.

Treatment:

Except for craniosynostosis surgery, there is no treatment that will enlarge your child's head or reverse microcephaly complications. Treatment focuses on coping strategies for your child's condition. Early childhood intervention programs, such as speech, physical, and occupational therapy, may help your child develop new skills.