Anterior fontanelle

Dr Henry Knipe and Dr Neil Lall et al.

The anterior or frontal fontanelle (or fontanel) is the diamond-shaped soft membranous gap at the junction of the coronal and sagittal sutures. It persists until approximately 18-24 months after birth, after which it is known as the bregma. The fontanelle normally measures between 0.6-3.6 cm (mean 2.1 cm) 2. It is the largest of the fontanelles and is the main sonographic window for performing cranial ultrasound.

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Article information

rID: 62358
Section: Anatomy
Synonyms or Alternate Spellings:
  • Frontal fontanel
  • Frontal fontanelle
  • Anterior fontanel

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Cases and figures

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