Microcephaly is an abnormally small head due to a small brain. With microcephaly, the head circumference is half the norm (according to some reports, the head circumference is even 3 times less).
Microcephaly can be from birth or appear in the first year of a baby’s life. The head stops growing (the brain does not increase), but with all this, the face develops as in a normal healthy person. As a result, the baby has a small head, a large face and a sloping forehead. As the baby grows in length, it becomes more obvious that the head is very small.
The causes of microcephaly can be any factors, for example, radiation, infections, drugs, genetic disorders, etc. Congenital microcephaly can be caused by intrauterine infections (rubella, cytomegalovirus, toxoplasmosis).
Microcephaly is characteristic of such syndromes as:
- trisomy 18 (Edwards syndrome)
- trisomy on chromosome 13 (Patau syndrome)
- crying cat syndrome
- Miller’s cider
- Prader-Willi syndrome, etc.
- fetal alcohol syndrome
The mass of the brain with microcephaly is sharply reduced, sometimes up to 500-600 g. Signs of gross malformations are found in the brain: macro- and microgyria, lisencephaly, agenesis of the corpus callosum, heterotopia. The frontal and temporal lobes of the brain are especially reduced, so that its islet remains uncovered. The convolutions are flattened, there are no tertiary convolutions and furrows. The basal ganglia are more developed than the cerebral cortex. The optic tubercle, brain stem, cerebellum, pyramids of the medulla oblongata are not often reduced.
Diagnosis is simple and is based on the presence of a reduced head size and the detection of underdevelopment of the intellect. Microcephaly is differentiated from craniostenosis, which is characterized by changes in the craniogram.
As such, there is no specific treatment for microcephaly. Treatment is focused on the removal of emerging symptoms, that is, it is symptomatic. On average, the life expectancy of people with microcephaly is reduced and the prognosis for normal brain function is poor.
With primary microcephaly, education in a special school is possible in some cases. Children with secondary microcephaly need constant care.