Overview
A tense or bulging fontanelle occurs when fluid accumulates in the skull cavity or when pressure increases in the brain. Common causes are hydrocephalus or increased intracranial pressure due to illness.
Review Date 1/17/2025
Updated by: Charles I. Schwartz, MD, FAAP, Clinical Assistant Professor of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, General Pediatrician at PennCare for Kids, Phoenixville, PA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.