This 3 year-old patient presented with head deformity. There are bilateral bony protruberances from the parietal bones, which are seen to be due to thickened calvarium on the source images. This is the typical appearance of ossified cephalohaematomas.

A cephalohematoma is a traumatic subperiosteal hematoma which is bounded by the periosteum and cannot cross sutures. This distinguishes it from a subgaleal hematoma, which does cross sutures. Cephalohematomas occur in 1%–2% of live births.The incidence increases after forceps extraction. Cephalohematomas usually gradually incorporate into the calvaria by ossification. Cephalohematomas may be unilateral or bilateral.

Reference:
Glass RBJ, et al. The Infant Skull: A Vault of Information. RadioGraphics 2004; 24:507–522
Credit: Dr Laughlin Dawes
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