Rapidly calcifying and ossifying epidural hematoma.

Conservative treatment of an epidural hematoma is not always effective in children. We describe an 8-year-old boy who had been followed up conservatively for 10 days at a local hospital due to acute epidural hematoma. A new CT revealed an expansion of the former hematoma accompanied by a thick hyperdense layer. Because the patient presented with symptoms of elevated intracranial pressure, an immediate craniotomy was performed to evacuate the hematoma. The ossified layer, which was densely adhered to the dura mater, was also completely removed. Rapid ossification and/or calcification of an epidural hematoma appearing 10 days after a head injury have not been reported previously. Possible mechanisms of rapid ossification are also discussed in relation to the present report, and the relevant literature is reviewed.