Imaging Features of Craniofacial Giant Cell Granulomas: A Large Retrospective Analysis from a Tertiary Care Center.

Background and Purpose: Craniofacial giant cell granulomas are rare lesions with varied appearances on imaging. We aimed to describe the imaging features of giant cell granulomas of the craniofacial bones.
Materials and Methods: A retrospective analysis of the clinical features and imaging findings of 20 histopathology-proved cases of craniofacial giant cell granulomas, dating from 2006 to 2022, was performed.
Results: Of the 20 cases, 10 each were seen in men and women. The epicenter of the lesions varied in location: in the maxilla in 8 patients, in the mandible in 5, in the temporal bone in 3, in the sphenoid/clivus in 3, and in the orbit in 1 patient. On the radiographs, the lesions appeared well-circumscribed, expansile, and lytic. On CT, the lesions were predominantly multiloculated, with thin septa, a soft-tissue component, and with expansion and remodeling of the underlying bone. On MR imaging, the solid component of the lesions was isointense on T1WI and hypointense on T2WI, with heterogeneous enhancement of the solid component and rim enhancement of the locules. Fluid-fluid levels were present in 3 patients.
Conclusions: Giant cell granulomas commonly present as locally aggressive, expansile, multiloculated lytic lesions, with solid as well as cystic areas. The solid component is typically hypointense on T2WI. Certain key imaging features of giant cell granulomas can aid the radiologist in narrowing the differential diagnosis.
(© 2022 by American Journal of Neuroradiology.)