Ask the doctor: Why do some children have abnormally large heads?

Why do some children have abnormally large heads?

This most probably is a result of hydrocephalus. Hydrocephalus is a word derived from Greek – ‘hydro’ meaning water and ‘cephalous’ referring to the brain. Essentially, it is ‘water in the brain’. This is a condition where the amount of fluid in the brain medically referred to as Cerebrospinal Fluid (CSF) is increased.

Every human being produces CSF from the time they are born, which helps in the functioning and protection of the brain. But when there is blockage in passage of the fluid, it accumulates, and becomes too much, resulting in hydrocephalus.

A child can develop the condition before birth, known as congenital, or acquire it. The cause of congenital hydrocephalus is the blockage in the passage of CSF. A child may be born with a blockage in the pathway that allows fluids in the brain to flow normally. But if it has nowhere to go, it fills up the brain, a situation that results in the enlargement of the head.

Children and adults can acquire the condition through infections like meningitis, tuberculosis, bleeding in the brain, injury in the brain, or even a tumor that can grow and block the pathways.

Is there anything a pregnant woman can do to prevent hydrocephalus?

There is no known direct relationship between feeding of a woman during pregnancy and hydrocephalus. However, pregnancy care is key in the development of the baby. For example, if a mother acquires an infection in pregnancy, it can affect the brain of the foetus, resulting in blockage of fluid pathways.

Can the condition be detected in an unborn child?

A mother does not have to wait until delivery day to know her baby’s health. Growth of a baby should closely be monitored before birth during antenatal clinics by doing regular ultrasound scans. However, if at birth the baby’s head is larger than normal circumference, this may require C-Section delivery.

After birth of a normal looking baby, other symptoms such as convulsions, poor feeding, prominent veins on the scalp, skull bones appearing separated and eyes appearing to look downwards (setting sun sign)  may be indicative of hydrocephalus.

Can a baby with hydrocephalus grow into an otherwise normal functioning adult?

It is worrying that we have myths even among healthcare providers that such children do not grow into adulthood. Hydrocephalus is not a death sentence. Children born with such conditions do grow into adulthood, as long as the condition is diagnosed and treated early. At an advanced stage, the likelihood of severe complications and death is high.

What is the right time to see a doctor?

There should be no waiting. If a child has a big head, or any other health condition, consult a specialist. Delays can lead to complications that cannot be treated.

How do doctors confirm that a baby has hydrocephalus?

The most common initial diagnostic test to determine hydrocephalus is through an ultrasound of the baby’s head.

This is why we encourage mothers to adhere to antenatal clinics. Ultrasound is done at between 15 and 35 weeks of gestation.

A CT scan of the brain can be used to make a diagnosis after birth. A healthcare giver measures the circumference of the baby’s head, and this should be in line with the normal range for the baby’s age.

If the head is large, it is a sign that the baby might be having hydrocephalus, and requires further evaluation.

How successful is the treatment of hydrocephalus?

The condition can be treated by either removing the cause of CSF obstruction or diverting the excess fluid.

Early diagnosis gives the best chance for successful treatment.

Treatment is through surgery done either by inserting a device known as a shunt into the brain, or through a procedure called Endoscopic Third Ventriculostomy (ETV).

A shunt is a flexible tube with a catheter and a valve that is placed under the skin to drain excess fluid from the brain into the abdomen. The device allows pressure in the brain to normalize by draining the fluid into the abdominal cavity, where the fluid can be reabsorbed.

Once placed, a shunt stays in the body for the life of the patient.

ETV, on the other hand, is an operation that creates an opening in the floor of the third ventricle in the brain, allowing fluid to flow into its normal pathway.

What does this treatment cost?

It might be expensive because of the equipment used. For example, a shunt costs between Sh7,000 and Sh9,000, in addition to the hospital fees. Fees in private hospitals are higher, as compared to public hospitals. We, therefore, encourage the public to enroll for National Health Insurance Fund to cover such costs.

What would be the long-term effects of the condition to the child?

Children or adults with the condition may have abnormalities in the brain and delayed development. Some may develop intellectual challenges.

How common is hydrocephalus in Kenya?

Data on hydrocephalus nationally and globally is not accurately documented, although globally, some researches reveal that about 3 of every 1,000 children born have the condition. It is, however, common in Kenya because almost every doctor has had a chance to treat such babies after birth or during clinic reviews.

By Dr Lee Ogutha as told to Mercy Kahenda. Dr Ogutha is a consultant neurosurgeon and lecturer at Maseno University School of Medicine.