Anterior fontanelle

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== Anterior Fontanelle ==

The anterior fontanelle is the largest of the fontanelles (soft spots) on a newborn's skull. It is located at the junction where the two frontal bones and the two parietal bones meet. This diamond-shaped area is crucial for the birth process and the early development of the infant's brain and skull.

Anatomy

The anterior fontanelle is typically about 2.1 cm by 2.1 cm in size at birth, although this can vary. It is bordered by the frontal bone anteriorly and the parietal bones posteriorly. The fontanelle allows for the overlapping of the cranial bones during childbirth, facilitating the passage through the birth canal. It also provides the necessary space for the rapid growth of the brain during the first year of life.

Development

The anterior fontanelle usually closes between 12 to 18 months of age. The closure is a gradual process where the cranial sutures (the fibrous joints between the bones of the skull) ossify and the bones fuse together. The timing of closure can vary, and delayed closure can be a sign of certain medical conditions.

Clinical Significance

The anterior fontanelle is an important indicator of an infant's health. It can be palpated to assess intracranial pressure, hydration status, and developmental anomalies. A sunken fontanelle may indicate dehydration, while a bulging fontanelle can be a sign of increased intracranial pressure, which may be due to conditions such as hydrocephalus or meningitis.

Examination

During routine pediatric check-ups, the anterior fontanelle is examined to ensure it is closing appropriately and to check for any abnormalities. The fontanelle should feel firm and slightly concave. Any significant deviations from the norm may warrant further investigation.

Related Conditions

• Craniosynostosis: A condition where one or more of the cranial sutures close prematurely, affecting the shape of the skull and potentially leading to increased intracranial pressure.
• Hydrocephalus: A condition characterized by an abnormal accumulation of cerebrospinal fluid within the brain, which can cause the fontanelle to bulge.
• Meningitis: An infection of the protective membranes covering the brain and spinal cord, which can also cause a bulging fontanelle.

See Also

• Fontanelle
• Cranial sutures
• Infant development
• Pediatric assessment