Lymphoscintigraphic abnormalities in the contralateral lower limbs of patients with unilateral lymphedema

The contralateral limbs of patients with unilateral lymphedema in the lower limbs (LLs) can exhibit abnormal lymphatic circulation, even in the absence of lymphedema. This idea is based on a number of reports that have studied isolated cases using lymphoscintigraphy. It is likely that these patients previously had some form of lymphopathy, and the lymphedema arose after the action of some external factor. However, there are no studies in the literature that adequately assess the asymptomatic contralateral limbs of these patients or address the prevalence and characteristics of the abnormal lymphatic circulation in these limbs. The aim of this study was to assess the prevalence of abnormal lymphatic circulation in the asymptomatic contralateral limbs of patients with unilateral lymphedema of the LL.

Forty-three patients from the angiology and vascular surgery ward of the Hospital das Clínicas da Universidade Federal de Pernambuco with unilateral lymphedema of the LL underwent lymphoscintigraphy. All patients received a subcutaneous injection of 0.2 mL (74 MBq) of a solution of dextran 70 labeled with technetium Tc 99m in the first interdigital space of each foot. Images were obtained on two occasions: 10 minutes and 1 hour after the injection. The study design was transversal prospective.

Among the 43 asymptomatic LLs, 30 (70%) showed abnormal lymphatic circulation. The lymphoscintigraphic abnormalities found were the following: reduced visualization of the lymphatic vessels and lymph nodes during 1 hour (83%), collateral circulation (30%), visualization of the inguinal and pelvic lymph nodes after at least 1 hour (30%), visualization of the popliteal lymph nodes (20%), dilation and lymphatic tortuosity (20%), and dermal backflow (10%).

In this study,70% of the patients with unilateral lymphedema of the LL had some form of lymphopathy in the contralateral limb during the lymphoscintigraphic examination. These findings could favor the early treatment of these patients to prevent the disease from progressing to its most severe stage.