Abstract P33: Validation of Vectra 3D Imaging for Quantitative Volumetric Measurement of Upper Extremity Lymphedema

Abstract

BACKGROUND: Secondary lymphedema of the arm is a complication of lymph node removal in cancer surgery. Limb volume measurements are considered the gold standard in evaluating outcomes in upper limb lymphedema. However, current techniques for volume measurement are limited by a lack of sensitivity to localized changes. The aim of this study was to determine whether the Vectra 3D imaging system could feasibly achieve accurate volume measurements of the upper limb. METHODS: A feasibility study was performed in 10 patients with lymphedema of the upper limb. Vectra 3D software was used to generate images and calculate volume of the hand, forearm, and upper arm. These measurements were compared to circumference (tape) and water displacement measurements. RESULTS: Ten patients with lymphedema of the arm were enrolled for volume measurement. Arm volumes ranged from 1517 to 4050 cc. The Vectra 3D provided precise volume measurements (average standard deviation +/- 0.8%). Measurements of the forearm and upper arm correlated with circumference measurements (R2 = 0.991) and were in good agreement, with the mean difference between measurement techniques being 2.8 ± 2.0%. Three dimensional measurements of hand, forearm, and upper arm also correlated with water measurements (R2 = 0.994) and had a mean difference between measurement techniques of 2.2 ± 1.8%. CONCLUSIONS: The Vectra 3D provides accurate and precise data comparable to the most commonly used technique to estimate limb volume (tape measurement) and gold-standard water volume measurement. Three dimensional imaging also offers several advantages, including time efficiency and obtaining localized measurements.