Volume Measurements and Follow-Up

Measurement of extremity volumes with plethysmography or indirect via circumference measurement is essential for assessing the size of the lymphedema and for treatment monitoring. It is important that both the normal and diseased limb is measured in exactly the same way at all time points to eliminate natural volume variations. The normal arm volume variations are between 2 and 13 % in healthy individuals. The dominant arm is usually about 1.5 % larger. Lymphedema is usually defined as a relative extremity volume difference > 10 % (the edematous extremity is 10 % larger than the normal). Both plethysmography and circumference measurements are useful and show satisfactory validity and reliability; plethysmography is recommended if only one method is used.