Why are legs wrapped with elastic bandages before a radionuclide venogram?

The wrapping of legs with elastic bandages before a radionuclide venogram serves the purpose of suppressing superficial circulation. This technique is important because it reduces the blood flow in the superficial veins, thereby allowing for a clearer distinction between the deep venous system and superficial venous flow during the imaging process.

By applying elastic bandages, the superficial veins are compressed, minimizing their contribution to the overall blood volume in the area being examined. This enhances the ability of the radionuclide to outline and visualize the deep veins more effectively, leading to improved diagnostic accuracy in identifying conditions such as deep vein thrombosis or other venous disorders.

In contrast, the other options do not accurately reflect the purpose of using elastic bandages in this context. For instance, preventing blood clots from traveling to the lung relates more to interventions post-procedure rather than during imaging, and trapping the tracer in the lower extremities is not a function of bandaging; instead, the distribution of the radionuclide is determined by blood flow dynamics during imaging. Distending veins in the feet is also not relevant as the compression from the bandages would not serve this purpose, and the focus during a venogram is on visualizing the deep venous system rather than distending