The device is diagnostic in purpose. ImpediMed’s L-Dex 400 technology utilizes the characteristics of frequency dependent current flow to quantify changes in extracellular fluid in the patient’s limb. These changes can assist the surgeon or oncologist in clinically assessing early signs of lymphedema. The L-Dex technology is specific for extracellular fluid and is unaffected by changes in the patient’s weight due to a change in fat mass or muscle mass. As fluid accumulates, the L-Dex value increases on the scale. The L-Dex number provides an instant tool for assisting in the clinical assessment of lymphedema progression as well as an easy way to track change in the patient over time.
Thus far, this technology has been accepted in Ireland but not anywhere else. Bioimpedance technology has been acknowledged by the Irish Clinical Resource Efficiency Support Team (CREST) in its recently released (February 2008) Guidelines for the Assessment and Monitoring of Lymphedema which rates bioimpedance as the only technology high in sensitivity and specificity.
There is an emerging (but not yet emerged) consensus that supporys the need for a shift in treatment focus from a reactive approach to one focused on the early assessment and early intervention of the condition. Bioimpedance technology featuring high sensitivity and specificity may support this approach.
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