Absorption of subcutaneous injection of Tc-99m pertechnetate via acupuncture points and non-acupuncture points.

SC-RNV, a new method of radionuclide venography by subcutaneous injection of Tc-99m pertechnetate at acupuncture points K-3 (Taixi), was developed in our laboratory. To further investigate whether K-3 is the best point for SC-RNV, Tc-99m pertechnetate was subcutaneously injected at K-3 on one foot and at one of the 11 other acupuncture points (APs) or 3 nonacupuncture points (NAPs) on the opposite foot, simultaneously, in 157 subjects without evidence of venous disorder. The absorption of radioisotopes from each injection site was evaluated by analyzing the time-activity curve at a region of interest set upon over the lower leg above the injection site. The results revealed that the absorption of radioisotopes via K-3 (Taixi) was better than that via NAPs, evidenced by higher peak activity and greater absorption rate. However, there was no significant difference between K-3 injection and other APs injections except Liv-2 and Liv-3. These results indicate that absorption of radioisotopes via APs is better than via NAPs. This together with the fact that K-3 is easier to detect than other APs in feet, suggests that K-3 is a good point for SC-RNV.