What is Microcephaly?

What is Microcephaly? Microcephaly is a rare medical condition in which the circumference of an infant's head is smaller than normal because the brain has not developed properly or has stopped growing. Microcephaly can be present at birth or it may develop in the first few years of life.  It is most often caused by genetic abnormalities that interfere with the growth of the brain during the early months of fetal development. What causes Microcephaly? Microcephaly is either caused by exposure to harmful substances during the fetal development, or it may be associated with genetic problems or syndromes that may have a tendency to run in families.  Causes of Microcephaly may include: Fetal alcohol syndrome Decreased oxygen to the fetal brain (cerebral anoxia) due to pregnancy complications or complications during delivery Craniosynostosis — the premature fusing of the joints (sutures) between the bony plates that form an infant's skull Chromosomal abnormalities such as Down Syndrome Infections of the fetus during pregnancy, such as toxoplasmosis, cytomegalovirus and measles (rubella) Maternal abuse of illegal drugs Untreated phenylketonuria Microcephaly can occur alone or in association with other health problems, and may occur from inheritance of an autosomal recessive, or rarely, an autosomal dominant gene. Acquired Microcephaly may occur after birth due to various brain injuries such as lack of oxygen or infection. What are the symptoms of Microcephaly? The following are the most common symptoms of Microcephaly. However, each child may experience symptoms differently. Symptoms may include: appearance of the baby's head is very small high-pitched cry poor feeding seizures increased movement of the arms and legs (spasticity) developmental delays facial distortion dwarfism or short stature mental retardation The symptoms of Microcephaly may resemble other conditions or medical problems. Always consult your child's physician for a diagnosis. How is Microcephaly diagnosed? Microcephaly may be diagnosed before birth by prenatal ultrasound, a diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels. In many cases, Microcephaly may not be evident by ultrasound until the third trimester, and, therefore, may not be seen on ultrasounds performed earlier in pregnancy. The diagnosis of Microcephaly may be made at birth or later in infancy. The baby's head circumference is much smaller than normal. During the physical examination, the physician obtains a complete prenatal and birth history of the child. In older babies and children, the physician may also ask if there is a family history of Microcephaly or other medical problems. The physician will also ask about developmental milestones since Microcephaly can be associated with other problems, such as mental retardation. Developmental delays may require further medical follow up for underlying problems. A measurement of the circumference of the child's head is taken and compared to a scale that can identify normal and abnormal ranges. It's important to note that heads with circumferences in the 1st, 2nd and 3rd percentiles are just small heads. Microcephaly is a head circumference that is significantly below the 1st percentile. Diagnostic tests that may be performed to confirm the diagnosis of Microcephaly and identify abnormalities in the brain include: head circumference - this measurement is compared with a scale for normal growth and size.   x-ray - a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.   computed tomography scan (Also called a CT or a CAT scan.) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including bones, muscles, fat, and organs. CT scans are more detailed than general x-rays.   magnetic resonance imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.   blood tests   urine tests Is there any treatment?   There is no treatment for Microcephaly that can return a child’s head to a normal size or shape. Treatment focuses on ways to decrease the impact of the associated deformities and neurological disabilities. Children with Microcephaly and developmental delays are usually evaluated by a pediatric neurologist and followed by a medical management team. Early childhood intervention programs that involve physical, speech, and occupational therapists help to maximize abilities and minimize dysfunction. Medications are often used to control seizures, hyperactivity, and neuromuscular symptoms. Genetic counseling may help families understand the risk for Microcephaly in subsequent pregnancies What is the prognosis? Some children will only have mild disability.  Others, especially if they are otherwise growing and developing normally, will have normal intelligence and continue to develop and meet regular age-appropriate milestones.  posted 02-08-08

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