Unilateral exophthalmos associated with severe fibrous dysplasia

Fibrous dysplasia is a benign developmental anomaly of bone, often affecting craniofacial bones. We report on a 9-year-old boy, who presented for routine checkup. Clinical examination revealed unilateral exophthalmos of his left eye without decrease of visual acuity or double vision. Radiologic studies showed characteristic extensive changes of fibrous dysplasia involving the left frontal bone, left orbital bones, maxillary and sphenoid bones. The patient was started on conservative therapy and the condition of the affected eye remained stable. As fibrous dysplasia of the orbital bones can be a cause of significant dysfunction and a treatable cause of blindness, early diagnosis is very important. These patients are most likely to present with complaints of facial asymmetry, including axial, vertical, or horizontal displacement of the globe, or visual loss. Therefore the ophthalmologist plays an important role in the early diagnosis of fibrous dysplasia.