When Lymphoedema is present, lymph and other fluids build up in the interstitial spaces of the tissues. This results in an overall increase in the total amount of extracellular fluid (ECF) in the limb, causing swelling. This can be documented by measuring the impedance (opposition) to a low frequency current that has been passed into the limb. Low frequency current travels predominantly through the ECF, where the Lymphoedema manifests. As the fluid builds up in the limb, the impedance to the current decreases and it is in this way that low frequency bioimpedance is able to assess Lymphoedema.~Multi-frequency bio-impedance analysis otherwise known as Bioimpedance Spectroscopy (BIS) has been reported to be effective for the measurement of ECF and sub clinical changes in ECF to predict the onset of Lymphoedema in the arms in studies conducted by Cornish et al. It has been reported by Warren et al that BIS can be used as a reliable and accurate tool for documenting presence of lymphoedema in patients with wither upper- or lower-extremity swelling.~The Imp™ XCA device uses an impedance ratio methodology to assess unilateral Lymphoedema of the arm. By this method the unaffected arm acts as an internal and subject specific control. The Imp SFB7+ (L-Dex U400) uses the same principles but at a lower frequency. This study is designed to show the equivalence of the 2 devices in assessing unilateral Lymphoedema of the arm.
The purpose of this project is to prove that the Imp™SFB7+ (L-Dex U400) is equivalent to the Imp™ XCA device in assessing Lymphoedema. The Imp™ XCA device is a simple device capable of assessing Lymphoedema of a single arm. The Imp™SFB7+ (L-Dex U400) is a more complex device capable of assessing Lymphoedema in a larger population of Lymphoedema sufferers. The Imp™SFB7+ (L-Dex U400) will be developed to assess patients with Lymphoedema in their arms or their legs. The Imp™ XCA and Imp™ SFB7 are both TGA approved devices. The Imp™ SFB7+ (L-Dex U400) is similar to the Imp™ SFB7 the changes are to the software and user interface.