Sequential computed tomography images demonstrating characteristic changesin fibrous dysplasia

Images of fibrous dysplasia (FD) on computed tomography (CT) or magnetic re sonance imaging (MRI) vary depending on the relative proportions of the fib rous and osseous components. Based on analysis of the literature, Camilleri suggested that structural changes revealed by conventional radiography may be indicative of the progression of FD. Here we describe the case of a boy who presented at 12 years of age with monostotic FD located in the right m axilla. The lesion first appeared as a lamellar, 'onion peel'-like structur e on CT; then over the course of the next five years, the structure became what has been termed an 'egg-shell lesion', before eventually assuming the form of a 'ground-glass lesion'.