- Fontanelles are fibrous, membrane-covered gaps between cranial bones.
- A newborn has six fontanelles: anterior, posterior, two mastoid, and two sphenoid.
- Anterior and posterior are the most prominent
- The posterior fontanelle usually closes by 1-2 months of age.
- The anterior fontanelle usually closes between 7-19 months of age.
- A bulging fontanelle represents increased intracranial pressure, which may be transient and either benign or malignant.
- Meticulous history and physical is essential to guide management of these infants.
- Bulging fontanelle
- Congestive Heart Failure
- Space-occupying lesions
- Thyroid disorders
- Intracranial Hemorrhage
- Parathyroid disorders
- Brain Abscess
- Diabetic Ketoacidosis
- Hypervitaminosis A
- Lead encephalopathy
- Inborn errors of metabolism
- Roseola Infantum
- Idiopathic Intracranial Hypertension (Pseudotumor Cerebri)
- Dural sinus thrombosis
- Viral syndromes
- Clinical diagnosis
- Evaluate for underlying etiology
- Standard approach:
- Head CT
- LP (if not contraindicated by CT findings) with opening and closing pressures
- Treat underlying pathology
- See elevated ICP