[A case of cystic craniofacial fibrous dysplasia].

Introduction: Fibrous dysplasia is a benign, idiopathic, fibro-osseous disease.

Clinical Case: A 17-year-old girl had presented with left proptosis for the previous two years, associated to homolateral hemicranial pain. Clinical examination was normal except for non-reducible axile exophthalmia. Computed tomography and magnetic resonance imaging of the head revealed an extensive cystic tumor of the left fronto-ethmoido-sphenoidal region, with compression of the left frontal lobe and medial orbital wall. The radiological appearance suggested a mucocele but histological examination, after surgery, proved a fibrous dysplasia.

Discussion: Fibrous dysplasia with fronto-sphenoido-ethmoidal localization may be misdiagnosed as mucocele. Histology proves the diagnosis.