Causes of focally increased radiotracer activity on Tc-99m SC liver-spleen scintigraphy include vena caval obstruction, Budd-Chiari syndrome, focal nodular hyperplasia, and tricuspid insufficiency. Artifactually increased activity may result from a malpositioned central venous catheter, free pertechnetate in the stomach, or an overlying breast. An unusual variation of this last artifact, also known as the "hot stripe sign," was encountered during routine liver-spleen imaging of a 65-year-old woman who had breast carcinoma.
