When performing radionuclide venography with 99mTc MAA, at which site is the radiopharmaceutical administered?

In radionuclide venography using 99mTc macroaggregated albumin (MAA), the radiopharmaceutical is typically administered into the dorsal veins at the top of each foot. This site is chosen because it allows for optimal visualization of the venous structures in the lower extremities and ensures that the injected material travels through the venous system of the legs. By utilizing the dorsal veins, the distribution of the radiopharmaceutical can be effectively imaged as it provides clear pathways through which the tracer will flow towards the larger veins and facilitate thorough examination of potential vascular issues.

Administering the radiotracer in the femoral vein, metacarpal vein, or anticubital area would not provide the same effective visualization needed for specific studies related to lower extremity venous circulation, which is why the dorsal veins of the feet are the preferred site for this procedure. This choice aligns with standard practices in nuclear medicine, ensuring both safety and accurate diagnostic results.