THE POTT puffy tumor represents frontal osteomyelitis with subperiosteal (pericranial) abscess, secondary to frontal sinusitis. Sir Percival Pott, an English surgeon, recognized in 1760 that inflammation of the dura mater and the formation of matter between it and the skull, in consequence of contusion, is generally indicated by one sign, a puffy, circumscribed indolent tumor of the scalp, and a spontaneous separation of the pericranium from the skull under such tumor.1Pott puffy tumor is one of several potential complications of infection of a frontal sinus. Although a significant decrease in the incidence of disease of the frontal sinuses has occurred since the advent of antibiotics, frontal sinusitis still occurs in clinical practice and may follow a clinical course not unlike that observed during the preantibiotic era. Cranial and intracranial extension from infection of a frontal sinus may cause osteomyelitis, cavernous sinus thrombosis, meningitis, subdural empyema, and subperiosteal, epidural,