Thrombophlebitis-Demonstration by Scintiscanninq

Abstract

We have noticed that collections of radiotracer in the axillary regions are occasionally seen in patients who have undergone pulmonary scanning (Fig. 1). Almost without exception such patients have previously been subjected to venous catheterization for the purpose of administering intravenous fluids. Accumulations of tracer generally are punctate in appearance and are seen either during the time that the catheter is in place, where injection is made through the catheter, or for several weeks following the removal of the catheter. An explanation that appeared reasonable to us was that the endothelial injury with associated clot (fibrin) deposits on the wall of the injured vessel trapped particles of albumin as they passed. An attraction for the macroaggregates of albumin by the fibrin was postulated. The thesis was tested in the laboratory by preparation of a Petri dish filled with serum mixed with macroaggregates of albumin tagged with 99mTc (Fig. 2). This experiment was interpreted as confirming the ability of fibrin to attract and collect macroaggregates of albumin. Microscopic studies revealed that the macroaggregates of albumin were gathered up in the lacy tentacle-like structure of the clot. By extrapolation it is felt that a situation similar to this exists in vivo and accounts for accumulation in the axillary region as seen on lung scans. In vivo demonstration of the same phenomenon was performed experimentally. Venous endothelial lesions were created in dogs by the use of a small polyethylene catheter through which was passed a small copper wire insulated except at its tip. Localized heat injury to the venous endothelium was created. A mural thrombus was demonstrated by venography. Macroaggregates of albumin tagged with 99mTc were then injected upstream from the area of the lesion (Fig. 3). Thrombophlebitis induced by chemical methods was also demonstrated in vivo. A lesion in the forearm of a dog was created by the use of sodium morrhuate, and accumulation of tracer in the damaged vein was clearly seen. In view of the dramatic appearance shown in the experimental work, in which a segment of vein was subjected to injury and subsequently injected by the tagged particles of albumin at a point upstream, the method was applied to patients in whom thrombophlebitis was suspected. No contraindication to this use of the tracer was felt to be present in view of the fact that it has been used for several years as a pulmonary scanning agent. Results CASE I (Fig. 4): A male in his twenties with recurrent venous thromboses and hypercoagulability. The patient's brother had a similar thrombotic disease since the age of fifteen years. The paternal uncle and grandfather also gave a history of similar disease.