Diagnosis & Imaging
Fontanelle examination
Fontanelle examination is the assessment of a baby's soft spot, which provides clues about intracranial pressure.
In short: Fontanelle examination
- It assesses the soft spot's fullness and tension.
- A bulging or tense fontanelle can indicate raised pressure.
- It is best assessed when the baby is calm and upright.
- It is part of the routine examination in infants.
What it is
Fontanelle examination is the clinical assessment of a baby's soft spot (most often the anterior fontanelle) — checking whether it is soft and flat, tense, or bulging. It provides clues about the pressure inside the skull.
Understanding Fontanelle examination
Because the fontanelle is a membrane-covered gap between skull bones, it offers a window onto intracranial pressure. A normal anterior fontanelle is soft and flat (it may bulge slightly with crying or straining), while a persistently tense or bulging fontanelle when the baby is calm and upright can indicate raised intracranial pressure, as from hydrocephalus. A sunken fontanelle, by contrast, can suggest dehydration. The fontanelle is examined as part of routine infant care and is especially important in monitoring babies with or at risk for hydrocephalus, alongside head circumference and other signs.
Why it matters
Understanding fontanelle examination helps families see how the soft spot provides information about pressure inside the skull, and why a persistently bulging or tense fontanelle when the baby is calm is a sign to report.
Common questions
What does fontanelle examination assess?
The fullness and tension of the soft spot.
What can a bulging fontanelle indicate?
Raised intracranial pressure.
When is it best assessed?
When the baby is calm and upright.
Bottom line
Fontanelle examination assesses the soft spot for clues about intracranial pressure, with a persistently bulging or tense fontanelle indicating possible raised pressure.
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