Nonspecific tissue accumulation of diffusible radionuclide imaging agents in areas of inflammation.
Although many radiopharmaceuticals are "targeted" for specific tissues or organs, they may be incorporated into nonspecific sites to the extent that they are readily diffusible. There may be local hyperemia with "leaky" neovascularity or capillaries and perhaps also diminished lymphatic or venous removal from the affected area. Two cases are reported in which abscesses were visualized serendipitously. One was visualized on a Tc-99m MDP bone scan following nephrectomy, the other on a patient with a pelvic abscess and nonvisualized left kidney but with enhancement of the rim of a large pelvic abscess.