Imaging features of intraosseous hemangiomas: beyond the mobile spine and calvarium

Objective: Describe imaging features of intraosseous hemangiomas located outside of the mobile spine and calvarium. Materials and Methods: Imaging and medical records were retrospectively reviewed for cases of intraosseous hemangiomas located outside of the calvarium and mobile spine. Evaluation included patient demographics, histologic confirmation, and imaging characteristics. Results: Thirty-six patients were included (25 F, 11 M; mean age 54 ± 17 years, range 10–84 years) with 37 total lesions (70% axial and 30% appendicular skeleton). Mixed lytic and sclerotic features were identified on 83–85% radiographs and CTs. Amorphous increased density mimicking osteoid matrix was present on 38–45% radiographs and CTs. Classic honeycomb or radial pattern was identified on 45% of CTs. Osseous expansion and cortical permeation were common features. CT identified periosteal reaction in 24% of lesions. All hemangiomas had heterogeneous MRI signal and most moderately or avidly enhanced. Intralesional fat was identified on 78% MRIs, often as a minor component and only detected on 24% of CTs. A soft tissue mass was present on 52% of MRIs. FDG PET/CT mean SUVmax of 3.2 ± 0.6 (range 1.9–5.0). Lesional FDG activity relative to background marrow was increased in 75% of lesions. Lesions with cortical permeation had higher metabolic activity versus those without (3.5 ± 0.7 versus 2.2 ± 0.3, p = 0.041). Conclusion: Intraosseous hemangiomas outside of the mobile spine and calvarium demonstrate more aggressive imaging features compared to vertebral hemangiomas, including cortical permeation, soft tissue mass, amorphous increased density mimicking osteoid matrix, and increased FDG activity.