Practicality of the Lower Extremity Lymphedema Index: Lymphedema Index Versus Volumetry-Based Evaluations for Body-Type-Corrected Lower Extremity Volume Evaluation.

Abstract

Volume measurement is one of the most commonly used methods for lower extremity lymphedema (LEL) evaluation because of its objectivity. However, volume comparison between different patients with different body types may be inappropriate because body-type difference seems to significantly affect leg volume (LV). Twenty-seven nonedematous legs of 27 unilateral LEL patients were evaluated. The LEL index was calculated using circumferences and body mass index (BMI), and LV was calculated using a summed truncated cone model. The BMI of the examinees was classified into 3 groups: low BMI (BMI < 20), middle BMI (BMI, 20-25), and high BMI (BMI > 25). The LEL index, LV, LV divided by body surface area (LV/BSA), and LV divided by BMI (LV/BMI) were compared with the corresponding BMI groups. The mean (SD) LEL index was 218.6 (12.9), and the mean (SD) LV was 4081.3 (835.6) mL. Between the low-, middle-, and high-BMI groups, there were no significant differences in the LEL index [223.2 (11.4), 217.8 (13.3), and 214.6 (14.2), P > 0.5] or in LV/BMI [185.5 (9.2), 179.3 (11.3), and 175.7 (15.8) mL per kg/m, P > 0.3], whereas significant differences were seen in LV [3484.9 (366.0), 3924.4 (342.5), and 5387.7 (1038.4) mL, P < 0.001) and in LV/BSA [2404.3 (236.6), 2539.2 (141.4), and 3106.0 (460.8) mL/m, P < 0.001]. The LEL index and LV/BMI stayed constant regardless of BMI, whereas LV and LV/BSA significantly increased with increase in BMI. With simplicity of calculation, the LEL index would allow more practical body-type-corrected LV evaluation compared with volumetry-based evaluations.