Macrocephaly: causes, symptoms and treatment

The maturational development of the brain is a complex and delicate process. Although human beings are born having a very large head in relation to the body (especially if we compare ourselves with other animals), throughout the first decades of our lives our nervous system must still grow and develop so that we can reach a healthy adulthood.

However, during this process there are many things that could go wrong and, although they are rare, if they do appear, they have a great influence on our lives. Macrocephaly is an example of this .

What is macrocephaly?

Macrocephaly is a biological alteration whereby the head circumference is greater than expected for sex and age of a boy or girl. That is to say, the identification of the macrocephaly is made by taking measurements of the perimeter of the skull and checking if the cranial vault is larger than normal in healthy people. Therefore, macrocephaly is included in cranial growth disorders, a category to which microcephaly also belongs.

In addition, it is considered that for a correct study of each case of macrocephaly not only depends on a measurement, but it is necessary to do a follow-up to see how it evolves the size of the head in relation to the rest of the body and if the situation is getting worse with the passage of time.

This is because this proportion changes very fast during the first months of life and, in fact, between birth and 6 years the size of the body below the neck increases at high speed.

On the other hand, the concept of macrocephaly is not in itself a disorder but a term that is used to superficially describe an alteration.

How often does it appear?

Currently there are no statistics on the prevalence of macrocephaly that have been extracted from related research, but it is estimated that it is a rare malformation present in less than 5% of people .

However, as always in these cases, it is possible that certain poorly studied populations are more prone to suffer this type of complications during the first months of life, perhaps due to genetic issues or contamination. After all, during pregnancy you are very sensitive to external conditions, and small alterations can, in some cases, favor the appearance of diseases in the fetus .

In addition, it is believed that macrocephaly is more frequent in males and that it usually appears in pregnancy or in the first months of life, which is why Most cases are examples of infantile macrocephaly .

Causes

Macrocephaly can be produced by a great variety of alterations. Many times it is hereditary , while in others it is caused by injuries or complications during pregnancy or childbirth.

For example, many of the macrocephaly cases are due to a condition known as hydrocephalus , in which more cerebrospinal fluid (a substance that surrounds the brain and spinal cord) is produced than can fit inside the skull. This causes that in the first months of life the walls of the skull are more "dilated" than normal to accommodate so much fluid, since in this vital stage the head is much less hard than in adulthood.

Macrocephaly it can also be due to an abnormal growth of the skull or brain bones , which is compressed against the meninges and through it presses the bones of the cranial vault.

There is also other disorders in which macrocephaly may also appear , such as neurofibromatosis, alterations in bone growth, intracranial bleeding, Hurler syndrome or dwarfism.

Types of macrocephaly

There is a shallow classification that serves to distinguish between different types of macrocephaly according to their causes . However, it must be borne in mind that even within each type there are different variants that will depend on each individual case, such as the area where the skull bulges most or the most damaged areas of the brain.

In any case, the types of macrocephaly are the following:

Primary macrocephaly

This type of macrocephaly is characterized by caused by an increase in the volume and weight of the brain . For example, it occurs due to an abnormal multiplication of the stem cells. It has some genetic causes and is also known as macroencephaly.

Secondary macrocephaly

In this kind of macrocephaly, the increase of the skull is due to biological processes that are not due to an increase in the brain itself , but of other related substances that occupy the space of the head. For example, hydrocephalus produces this variant.

Macrocephaly due to bone malformation

Some cases of macrocephaly are explained by an abnormal development of the bones. For example, they may be due to an early closing of the cranial sutures, which produces a bulge caused by the abnormal development of the nervous system produced by the chain reaction that means not having space to expand at any given time.

Diagnosis and associated symptoms

In many cases macrocephaly It can be detected during the gestation stage thanks to the use of ultrasound. However, in non-congenital macrocephaly this may appear somewhat later, with the manifestation of certain disorders, and it is diagnosed in pediatric consultations .

Macrocephaly can have a great variety of associated symptoms, depending on their causes and the intensity of this alteration. Among them, the following stand out:

• Cognitive disorders
• Vomiting
• Convulsive crisis
• Delay of general development
• Headaches
• Intracranial hypertension
• Irritability

Some of these symptoms may subside with the passage of time and depending on the intervention that is made, although they can also become more intense, depending on the case.

Forecast

The way in which macrocephaly develops and its associated symptoms depends on the kind of alteration that this phenomenon is producing.

In some cases, such as those where there is hydrocephalus, the life of the person may be in danger if surgery is not performed (which will consist in exiting the excess cerebrospinal fluid). In others, neither the life nor the cognitive abilities of the child will be compromised. In fact, the Cases in which macrocephaly is not associated with the onset of mental retardation are very frequent .

Treatment

There is no specific treatment that targets the disappearance of macrocephaly . However, there are some that aim to intervene on the symptoms associated with the disorder that is causing this alteration.

Many of them are pharmacological and psychiatric, while others are psychological in nature and focus on the cognitive stimulation of the child.