Skeletal PET with F-18-fluoride: Applying new technology to an old tracer

Although F-18-labeled NaF was the first widely used agent for skeletal scintigraphy, it quickly fell into disuse after the introduction of Tc-99m-labeled bone-imaging agents. Recent comparative studies have demonstrated that F-18-fluoride PET is more accurate than Tc-99m-diphosphonate SPECT for identifying both malignant and benign lesions of the skeleton. Combining F-18-fluoride PET with other imaging, such as CT, can improve the specificity and overall accuracy of skeletal F-18-fluoride PET and probably will become the routine clinical practice for F-18-fluoride PET. Although F-18-labeled NaF and Tc-99m-diphosphonate have a similar patient dosimetry, F-18-fluoride PET offers shorter study times (typically less than 1 h), resulting in a more efficient workflow, improved patient convenience, and faster turnarounds of reports to the referring physicians. With the widespread availability of PET scanners and the improved logistics for the delivery of F-18 radiopharmaceuticals, prior limitations to the routine use of F-18-fluoride bone imaging have largely been overcome. The favorable imaging performance and the clinical utility of F-18-fluoride PET, compared with Tc-99m-diphosphonate scintigraphy, support the reconsideration of F-18-fluoride as a routine bone-imaging agent.