Radioisotope Phlebography

Abstract

The concept of utilizing radioisotopes in the detection of venous thrombosis is not new; however, there has been a recent flurry of research activity in this area. Table 1 lists most of the radiotracers which have been tried with varying degrees of success in humans and experimental animals. The most simple and convenient method of performing isotope phlebography is by using technetium-99m labeled albumin particles (macroaggregates or microspheres). These are readily available and are in routine use for pulmonary perfusion scintigraphy. These radiolabeled particles adhere to newly formed clots in vivo and appears as hot spots. Other findings on technetium-99m labeled albumin particle phlebography which suggest thrombophlebitis include non-visualization of a venous segment or system, collateral vessels and stasis of the radiotracer distal to the clot. When isotope phlebography, using ^99mTc macroaggregates or microspheres, is performed and interpreted properly, the accuracy is over 90% when compared to contrast phlebography.