Intraosseous hemangiomas are benign vascular lesions within osseous structures, often found incidentally in the spine. Their imaging appearance consists of a variable mixture of fat, vascular channels, and remodeled trabecular bone. Fat-rich lesions typically have characteristic findings, including but not limited to vertically-oriented trabeculae on radiographs, a "polka-dot" pattern on axial computed tomography (CT), a "corduroy" pattern on sagittal or coronal CT, and hyperintensities on both T1- and T2-weighted magnetic resonance imaging (MRI). Conversely, atypical lesions are lipid-poor and may be T1 hypointense and less conspicuous on CT. Imaging appearance may overlap with metastatic disease and other marrow-replacing processes. Aggressive hemangiomas represent an important clinical subset often characterized by osseous expansion, cortical disruption, and epidural or paravertebral extension, pathologic fracture, or neurologic compromise. In current practice, the evaluation of vertebral hemangiomas with nuclear medicine can be challenging due to highly variable and often non-specific radiotracer uptake. On technetium-99m (99mTc) bone scintigraphy, lesions are often inconspicuous, although decreased or increased uptake may occur. On fluorine-18 fluorodeoxyglucose (FDG) PET/CT, hemangiomas are usually non-avid or mildly avid, but occasional marked uptake should not be interpreted in isolation. Uptake on prostate-specific membrane antigen (PSMA)- and somatostatin receptor (SSTR)-targeted PET is similarly inconsistent. Regardless of the radiotracer used, correlation with prior imaging, particularly on CT and MRI, is more reliable than assessing radiotracer avidity alone. This review presents a practical multimodal framework for recognizing typical, atypical, and aggressive intraosseous hemangiomas in adult and pediatric presentations with common nuclear medicine interpretation pitfalls.
Acute medical conditions represent a significant and heterogeneous clinical burden, often requiring rapid and accurate diagnosis to guide timely management. Positron emission tomography/computed tomography (PET/CT), which integrates functional PET imaging with CT's anatomical detail, has expanded beyond its traditional oncologic applications and is being increasingly explored in acute or emergency settings. PET/CT, particularly with but not limited to 18F-fluorodeoxyglucose, represents a promising adjunct, offering unique pathophysiological insights that can complement conventional imaging, supporting diagnostic decision-making and patient management in select non-oncologic contexts. This review examines the evolving role of PET/CT in acute clinical scenarios, highlighting its ability to detect early metabolic or inflammatory changes that may precede structural abnormalities on conventional imaging modalities such as CT or MRI. It also highlights how further evidence is, nonetheless, still required to better define optimal clinical integration.
