Vectra 3D Imaging for Quantitative Volumetric Analysis of the Upper Limb: A Feasibility Study for Tracking Outcomes of Lymphedema Treatment.

Abstract

Secondary lymphedema of the upper limb is a common sequela following lymphadenectomy during oncologic surgery. The gold standard for evaluating treatment outcomes in upper limb lymphedema is limb volume measurement. However, current techniques lack sensitivity to localized changes. In this study, the Vectra 3D imaging system was used to accurately and precisely obtain volume measurements of the upper limb in patients with lymphedema. A feasibility study was performed in 11 patients with lymphedema and 22 upper extremities; 24 arms were evaluated in total. Three-dimensional images were taken of the upper extremities, and Vectra 3D software was used to calculate the volume of the hand, forearm, and upper arm. These measurements were compared to traditional circumference (tape) and water displacement measurements. The 24 arm volumes ranged from 1517 to 4050 cc. The Vectra 3D provided precise and accurate volume measurements (average SD ± 1.0 percent of total volume). Measurements of the forearm and upper arm correlated with circumference measurements (R = 0.991) and were in good agreement, with the mean difference between measurement techniques being 2.8 ± 2.0 percent. Three-dimensional measurements of hand, forearm, and upper arm correlated with water measurements (R = 0.990) and had a mean difference between measurement techniques of 2.6 ± 2.1 percent. The Vectra 3D system provides precise and accurate data comparable to those of 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 with high spatial resolution. Diagnostic, II.