Multidetector CT findings of calvarial eosinophilic granuloma.

Eosinophilic granuloma (EG) is a well-recognised benign form of Langerhans-cell histiocytosis. The estimated incidence of EG is 3-4 per million of the population. More patients are children and adolescents between the ages of 1 and 15 years. The value of plain films in the diagnosis of the EG is limited and the extent of the disease is better defined by multidetector CT (MDCT) scanning. MDCT scan with multiplanar and three-dimensional reconstruction image of the skull and brain clearly demonstrates bone destruction and soft-tissue involvement of the tumour. In this article we present the MDCT imaging characteristics of EG of the skull and discuss the differential diagnosis of this rare lesion with reference to recent literatures.