Fibrous Dysplasia

This coronal CT demonstrates marked deformity and expansion of the skull and facial bones, with a heterogeneous “groud-glass” appearance to the bone. This is a characteristic appearance of fibrous dysplasia.
Fibrous dysplasia is a benign tumour-like process with progressive replacement of normal bone with immature woven bone. It may be monostotic or polyostotic. Monostotic FD affects older children and young adults. Polyostotic disease presents earlier. McCune-Albright syndrome is polyostotic fibrous dysplasia, precocious puberty and cutaneous pigmented lesions. The disease tends to burn out in early adulthood, with polyostotic disease progressing for longer. Malignant transformation (osteosarcoma) is rare.
Morbidity arises from compression and displacement. Limited operative intervention may be helpful in selected cases.
References:
1. www.STATdx.com, Amirsys
2. Online Mendelian Inheritance in Man, Johns Hopkins University
Credit: Dr Laughlin Dawes
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