Posterior fontanelle

The posterior fontanelle or occipital fontanelle (or fontanel) is the triangular soft membranous gap at the junction of the lambdoid and sagittal sutures. It persists until approximately 3 months after birth, after which it is known as the lambda. It can be used as an additional sonographic window for performing cranial ultrasound to improve visualization of dependently layering intraventricular hemorrhage.

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Article information

rID: 62360
Section: Anatomy
Synonyms or Alternate Spellings:
  • occipital fontanel
  • occipital fontanelle
  • posterior fontanel

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