Frontal lobe atrophy after prolonged frontal bone defect.

After a frontofacial monobloc in a 12-year-old Crouzon patient, the frontal bone was lost to infection. The patient did not attend postoperative appointments and was lost to follow-up. Nine years later, he reappeared requesting surgical reconstruction. This was performed satisfactorily with a titanium plate; however, it became apparent later that he had considerable atrophy of the frontal lobes and had developed the unstable behavior of patients who have undergone a frontal lobotomy. The atrophy would appear to be the consequence of the long-term absence of the frontal bones and the resultant repetitive frontal lobe microtrauma. Frontal infection and subsequent loss of the frontal bone is a recognized complication of monobloc advancement for faciocraniosynostosis and is mainly caused by the communication between the oronasal cavities and the cranial base. The frontal bone defect would normally be repaired after a delay of 6 months to a year with no significant sequelae. We present the unusual case of a patient whose frontal defect was not reconstructed for 9 years and who, as a result, developed frontal lobe atrophy and subsequent severe psychologic and behavioral difficulties.