Clinical comparison of technetium-99m diphosphonate and pyrophosphate in bone scintigraphy: concise communication

Thirty patients had bone scintigraphy with both Tc-99m pyrophosphate (Tc-PPi) and Tc-99m diphosphonate (Tc-HEDP). The images were given a composite rating for quality and the basis of three sets of criteria, and were also compared for the number of lesions detected by each agent. The two agents provided no difference in scan quality. Nevertheless, in ten of the 30 patients, at least two of the three readers detected with Tc-HEDP lesions that were not seen with Tc-PPi, and in two such cases all three readers considered the Tc-PPi scan normal. In another of these ten, two of three readers felt the Tc-PPi image was norm, whereas all three detected the lesion with Tc-HEDP. The reverse never occurred (P less than 0.01).