Fibrous Dysplasia of the Clivus

OBJECTIVE Fibrous dysplasia is a developmental skeletal disorder that may lead to distortion, expansion, and weakening of the bone. Craniofacial involvement by this entity is well recognized and is known to cause neurovascular impingement and cosmetic deformity; fibrous dysplasia of the clivus, however, is unrecognized and seldom reported. Differentiating this entity from more aggressive disease processes affecting the clivus is central for the proper management of lesions in this area. We have studied fibrous dysplasia of the clivus with the goal of depicting its manifestations, outlining its management, and heightening awareness of this disease entity. METHODS We retrospectively reviewed our database and identified patients with the diagnosis of fibrous dysplasia of the clivus. The demographic data, the clinical and radiological findings, and the management of these patients were reviewed. RESULTS Eight patients who had experienced fibrous dysplasia of the clivus were identified. They either were asymptomatic (four patients) or presented with headache (four patients). Of the patients who presented with headache, one also had XIIth cranial nerve paralysis and another had dysphagia. The radiological findings for this entity were consistent, with typical findings of hypointensity on T1- and T2-weighted magnetic resonance imaging studies and ground-glass appearance on computed tomographic scans. Four of the patients in our series had pathological confirmation. Treatment was determined by the patient's symptoms. CONCLUSION Fibrous dysplasia should be considered in the differential diagnosis of lesions affecting the clivus. Its clinical and radiological presentations permit the establishment of the diagnosis. Its management is usually conservative, unless the patient presents with nerve compression or extensive symptomatic involvement of the condyle.