The outward curving of infants’ soft spot (fontanelle) is called bulging fontanelle. Fontanelle is firm and slightly curved inward in normal situations. Increased pressure or fluid buildup in the brain may lead to tense or bulging fontanelle. The condition might be accompanied by other symptoms, such as fever.
Read this post to learn more about the fontanelle, causes of bulging fontanelle, diagnosis, treatment, and when to seek medical care for bulging fontanelle in babies.
What Is Fontanelle In Infants?
The skull consists of several bones, of which eight bones enclose and protect the brain. Each bone meets at a joint called a suture. In adults, the sutures are closed, but in infants, there is a space between the sutures filled with a membranous tissue. The space between the sutures is called a fontanelle or soft spot.
The function of fontanelle is to allow the baby’s head to mold during delivery and support the brain’s growth during infancy. The sutures fuse over time due to the addition of minerals, and the soft spot eventually disappears.
Since the skull has multiple bones, a baby has multiple fontanelles that close at different stages of infancy and toddlerhood (1). The following are the most notable fontanelles and the age at which they usually close.
- Posterior fontanelle, situated in the back of the head, closes by one to two months of age.
- Anterior fontanelle, on top of the head, closes between seven and 19 months after birth.
It is normal for fontanelle to bulge when an infant cries, vomits, or lays down. However, bulging fontanelle in other situations can be an indication of pathologies in most babies.
Causes Of Bulging Fontanelle
An infant may have bulging fontanelle due to the following reasons (2)
- Hydrocephalus, a condition that causes fluid buildup in the skull
- High intracranial pressure
- Encephalitis, swelling of the brain tissue commonly associated with infections
- Meningitis, an inflammation of the brain membranes
- Intracranial hemorrhage
- Head trauma
- Hypoxic-ischemic injury due to deprivation of oxygen to the brain
- Congenital hypothyroidism
You may seek medical care to identify and begin treatment of causes since brain anomalies may lead to severe complications.
When To See A Doctor?
Prompt medical care is required if your baby has bulging fontanelle. Fever and drowsiness, along with bulging of soft spots, can be an indication of serious illnesses. You may seek immediate emergency care in such situations.
You may even contact the doctor if the fontanelle is bulging, yet the baby remains calm and has no other symptoms.
Prevention Of Bulging Fontanelle
There is no specific way to prevent bulging fontanelle in infants since it can be due to various reasons. Giving vaccinations as per the schedule and maintaining hygiene may help avoid a few infectious diseases that lead to soft spot bulging. Baby-proofing your house and using good-quality cribs or strollers could prevent accidents and reduce the risk of head injury.
Diagnosis Of Bulging Fontanelle
Medical history and physical examination may help to identify bulging fontanelle and its causes. The following tests are usually ordered to confirm the diagnosis (3).
- Lumbar puncture or spinal tap
- Blood tests
- CT scan of the head
- MRI scan of the head
Treatment For Bulging Fontanelle
The treatment options may vary according to the cause and may include the following.
- Brain infections are treated with antibiotics or antivirals, depending on the etiologic agents.
- Surgical procedures may be performed to create shunts in hydrocephalus to drain excess fluid
- Surgical removal of tumors is done if present
- Thyroid hormone replacement therapy could help infants with thyroid abnormalities
- Intracranial pressure is managed with medications if present
Bulging fontanelle requires prompt treatment because if left untreated, it may increase the risk of permanent brain damage. It is best to see a doctor if you suspect your baby has bulging fontanelle, even if they display no other symptoms and are otherwise healthy. Early diagnosis of an underlying condition leads to timely treatment and better long-term outcomes for the growing baby.
2. The Abnormal Fontanel; The American Academy of Family Physicians
3. What Causes a Bulging Anterior Fontanelle?; Pediatric Education