Lymphoscintigraphy in the evaluation of limb edema.

Lymphedema is a chronic condition caused by ineffective lymphatic transport that results in edema and skin damage. Distinguishing lymphedema from other causes can be difficult. Lymphoscintigraphy is a simple and noninvasive functional test for the evaluation of the lymphatic system. (99m)Technetium-labeled sulfur colloid is injected intradermally at the interdigital web spaces of the upper/lower limbs. Once injected, the radiolabeled colloid particles travel through the superficial lymphatic channels. Thus, their lymphatic transport is monitored with dual-head gamma camera. The typical patterns of upper and lower limb lymphedema on lymphoscintigraphy are summarized in this section.