Radionuclide perfusion lymphangiography. An experimental technique to complement the standard ethiodol lymphangiogram

Radionuclide lymphangioscintigraphy in the evaluation of peripheral lymphedema

PURPOSE

The primary difficulty in evaluating and treating peripheral lymphedema is visualization of the lymphatics. Functional lymphatic studies have been performed on patients with peripheral edema to diagnose lymphedema, to determine its severity, and to understand the varied drainage patterns.

METHODS

After intradermal injection in the hands or feet, initial flow and whole-body images were taken using Tc-99m human serum albumin in more than 700 patients with possible lymphedema.

RESULTS

Clear images of truncal lymph transport and draining lymph nodes were obtained, and pattern differences between primary and secondary lymphedema were seen. Follow-up studies showed any functional change in lymphatic dynamics.

CONCLUSION

Peripheral lymphatics can now be easily visualized. Because lymphangioscintigraphy can be performed before and after medical treatment, follow-up evaluation of patients with lymphedema is possible. The procedure is noninvasive, repeatable, easy to perform, and harmless to the lymphatic endothelium.

Lymphoscintigraphy via the targeting of macrophages with 99mTc-J001X poly-galactoside in a model of pyogranulomas developed in sheep lymph nodes

Lymphoscintigraphy usually involves labeled microparticles or colloids that distribute in the lymph flow. A new strategy for imaging pathological lymph nodes would be the targeting of macrophages recruited in these lesions. The potential for lymphoscintigraphy of the highly diffusible J001X acylated polygalactoside labeled with 99mTc was studied and compared to usual colloidal agents in a model of infectious granulomas developed in sheep. Scintigraphic and histological assessment of the specificity of targeting was performed using a MAb (OM1) raised against ovine macrophages taken as reference. This study has evidenced the ability of J001X specifically to image pathologic lymph nodes and more especially the second lymph node in the same chain with a significant scintigraphic contrast.

Lymphoscintigraphy in lymphedema of the lower limbs using 99mTc HSA

Edema of the lower limbs is a difficult clinical problem. Edema could be due to stasis, obstruction of the lymphatic channels, or increased production of lymph beyond the drainage capacity of the lymphatic vessels. Sometimes it is difficult to differentiate among these varieties. Lymphoscintigraphy was performed in 164 patients complaining of swelling of the lower limbs, 2 women patients with lymphedema of the upper limbs following radical mastectomy, and 5 volunteers. All patients were injected with 1 mCi of 99mTc human serum albumin intradermally in the medial web on the dorsum of each foot. Data were acquired dynamically for both inguinal regions for forty-five minutes with a gamma camera interfaced with a computer. Static images were taken at ninety minutes for both legs and thighs and for the pelvis. Time activity curves were generated for the equal regions of inguinal nodes on both inguinal sides. The following patterns were recognized: normal pattern in 5 volunteers and in 57 patients, enhanced flow pattern in 17 patients, stasis with mild obstruction in 72 patients, and marked stasis with obstruction in 20 patients.

The biological characteristics of a water soluble porphyrin in rat lymph nodes

The biological characteristics of a radiolabeled metalloporphyrin, 5,10,15,20-tetrakis(4-carboxyphenyl)-porphinato [67Cu]copper (II) [( 67Cu]TCPP), in rat lymph nodes, surrounding muscle, fat, and blood were determined. Lymphatic tissue localized greater amounts of [67Cu]TCPP than did surrounding muscle and fat. Inflamed lymph nodes localized greater amounts of [67Cu]TCPP than did noninflamed lymph nodes. Time course studies suggest that the uptake of [67Cu]TCPP in noninflamed and in inflamed lymph nodes may involve different biological processes. The affinity of [67Cu]TCPP for inflamed lymph nodes may be influenced by the degree of inflammation. If further studies confirm these results, [67Cu]TCPP may be useful as a potential radiopharmaceutical for imaging inflamed lymph nodes.

Copper-67 labeled porphyrin localization in inflamed tissue

A series of experiments compared the uptake of 5,10,15,20 tetrakis(4-carboxyphenyl) porphinato [67Cu] copper (II), 67CuTCPP, by the lymph nodes of inflamed and two sets or control rats. The results demonstrate that 67CuTCPP localizes in greater concentration in inflamed lymph nodes than in noninflamed control lymph nodes. This enhanced uptake of 67CuTCPP by inflamed lymph nodes was 3.6 times greater than was the uptake by control lymph nodes. A time course study demonstrated that the uptake of 67CuTCPP by inflamed lymph nodes reached the maximum level by 24 hours post-injection of 67CuTCPP and remained constant throughout the 96 hours examined. It was also found that the uptake of 67CuTCPP by inflamed lymph nodes was not exclusively dependent upon an increase in the weight of inflamed lymph nodes. These studies show that 67CuTCPP has potential as a lymphoscintigraphy agent.

A direct comparison between subcutaneous and intralymphatic injections for lymphoscintigraphy

Lymphoscintigraphy using 99mTc colloids has been proposed as a simple adjunct to lymphangiography. To validate the technique of subcutaneous injection we performed a direct comparison between intralymphatic and subcutaneous administration of 99mTc-antimony colloid. In all cases excellent correspondence was obtained between the two techniques. Lymphoscintigraphy does not provide the same morphological information as lymphangiography, but can provide useful data regarding lymphatic obstruction.