Radiological diagnostic features of uremic leontiasis ossea: a case report

Uremic leontiasis ossea (ULO), which occurs in the craniomaxillofacial region, is a sign of terminal stage osteitis fibrosa cystica or brown tumors and primarily caused by secondary hyperparathyroidism induced by renal failure. Pathophysiological changes include osteoclasts or osteoblasts proliferation, bone resorption, bone decalcification, and connective tissue proliferation. In this paper, we report a case of a 24-year-old female patient, who was diagnosed with ULO and presented with multiple facial swellings. Imaging features included zonal patterns with alternating rings of hypo- and hyperattenuated craniomaxillofacial bones, and diffused mixed sclerotic tissues with lytic changes in CT imaging. T₁ weighted image and T₂ weighted image in MRI were characterized by alternating rings of low and intermediate signal intensity patterns. To the best of our knowledge, this case is the first example of pathologically proved ULO with maxillofacial MRI.