Patient's question:
A two-and-a-half-year-old girl, since birth, has been smaller in size compared to her peers. I would like to hear some opinions about microcephaly. Thank you.Doctor's answer:
Microcephaly can be divided into true microcephaly and relative microcephaly. True microcephaly is primarily caused by a chromosomal abnormality, or by exposure to radiation or intrauterine infection during fetal development, especially in the early stages of pregnancy. It is characterized by abnormally small or absent brain convolutions, significantly delayed brain development, and often halts progression by the third to fifth month of gestation. Affected individuals typically have a small, pointed head with a flattened forehead, a head circumference smaller than the chest circumference, which does not exceed 43 cm and can be as low as 25 cm or less. Brain weight is usually less than 900 grams, with a flat forehead and occipital region, premature closure of the anterior fontanelle, and early closure of all or part of the cranial sutures. Physical and intellectual development is delayed, along with language and behavioral impairments. Some patients may experience seizures, increased muscle tone, or even spastic paralysis. Prognosis varies depending on the degree of brain underdevelopment. Relative microcephaly, also known as pseudo-microcephaly, is caused by brain damage and atrophy due to inflammation or cerebrovascular injury. The reduction in head circumference is generally less severe than in true microcephaly.