Macrocephaly, also called macrocephaly, is a developmental defect, the most characteristic symptom of which is an enlarged head circumference (above the 97th percentile). The causes of macrocephaly are primarily genetic diseases and metabolic diseases. Early diagnosis allows you to identify the cause of the disease faster and start treatment.
Macrocephalyis a developmental defect, which may be one of the elements forming the syndromes of congenital defects and genetic diseases, it may occur independently or it may occur in isolation and in families. The cause of macrocephaly may be hydrocephalus. It is often detected in the womb during ultrasound examinations. The head measurement is performed each time during the ultrasound examination during pregnancy and immediately after delivery. The head of a newborn baby is measured from the browguard to the most posterior part of the occipital bone. If the measurement result is significantly higher (above the 97th percentile on the percentile grid) than the established norm for a given age and gender, it may indicate a large head.
Diagnostics in the first place includes tests to confirm or rule out hydrocephalus, the symptom of which is enlargement of the head circumference. The disease is the result of excessive accumulation of cerebrospinal fluid in the ventricular system of the brain and it is then necessary to perform, among others, tomography or magnetic resonance imaging of the brain, transcranial ultrasound, cysternography or examination of the cerebrospinal fluid. Other medical conditions where macrocephaly is one of the symptoms include:
- Sotos syndrome , also known as cerebral gigantism, is a rare genetic disease. In young children, decreased muscle tone, delayed development, and neurological problems are noted. In addition to the increased head circumference, other characteristic external features of the Sotos syndrome include a high forehead, hypertelorism, i.e. a wide set of eye sockets, a small mandible, a prominent chin, and bends in the frontal area and at the temples.
- Cowden syndrome- is a condition associated with several inherited genetic mutations. As a result, the risk of developing certain types of cancer is increased, including for thyroid cancer, bladder cancer, and in women additionally breast cancer or cancer of the uterus. The macrocephaly in Cowden syndrome occurs asone of the symptoms (in about 40% of patients).
- Alexander syndrome- a disease of the central nervous system, the characteristic symptoms of which are: large head, hydrocephalus, epileptic seizures, psychomotor retardation. Confirmation of the diagnosis is performed by performing tomography or magnetic resonance imaging of the head, where changes in the white matter of the brain are visible.
- Bannayan-Riley-Ruvalcaby syndrome- an extremely rare disease caused by a mutation of one of the genes. The external symptoms of the disease include, apart from macrocephaly, the presence of lipomas, polyps and skin lesions.
- Lujan-Fryns syndrome- a genetically determined disease caused, among others, by to developmental delay. Characteristic features are a large head, but also a small lower jaw, high forehead, not fully developed jaw, usually tall.
- Canavan syndrome- a disease of the central nervous system, classified as a metabolic disease. A malfunction of one of the enzymes leads to the degeneration of white and gray matter in the brain. Symptoms include: large head, decreased muscle tone, atrophy of the optic nerve, epileptic seizures.
- neurofibromatosis- a genetic disease that leads, among others, to for bone deformities, intracranial tumors, short stature, mental retardation and macrocephaly.
Macrocephaly: proper diagnosis
Basic diagnostics for macrocephaly include computed tomography or magnetic resonance imaging of the head. The doctor must determine the symptom of the disease of the large head in order to be able to order more detailed tests and decide on treatment.
Unfortunately, some of the above-mentioned genetic diseases are difficult to treat or incurable. It is worth mentioning, however, that sometimes a slight macrocephaly need not be a cause for concern. Parents often worry when their baby's head circumference is around the 90-97 percentile. If the research does not indicate any disease entity, and at the same time there is a tendency in the family for an increased head circumference, it may be the result of hereditary characteristics. Of course, it is worth observing the child's development and it is best when it is under the care of a specialist doctor.