Bio-Electrical Impedance Analysis is a non-invasive method that measures extracellular fluid proportion and impedance of related extremity by an advanced low intensity electrical current passes through body. It was stated that Bio-Electrical Impedance Analysis measures impedance ratio and it is useful in detecting lymphedema in an early stage. Bio-Electrical Impedance Analysis (BIA) gives important informations in the assessment of lymphedema by measuring directly tissue fluid changes. Lymphedema Index (L-dex) is found by dividing impedance ratios of unaffected extremity to affected extremity's impedance ratio with bio-electrical impedance analysis. Impedance of extremity lessens by developing lymphedema so L-dex value gets higher.