|Using Limb Girth or Volume Changes
Quantitative criteria for 'clinically manifest' limb lymphedema is somewhat arbitrary, but for unilateral limb involvement certain criteria are in use. These include conditions in which the affected arm as compared to the other arm has a girth greater than 2 cm or a volume greater than 200 ml or 10% (Stanton et al.,2000). Because of differences between normal paired-arms (up to 4%), slight volume changes encountered early on,and other factors, the use of such thresholds to detect sub-clincial lymphedema may not be satisfactory (Stanton et al., 2006). If presurgery measurements are made, then changes in limb girth at one or more sites along the arm, or arm volume changes from baseline, may be useful to indicate probable lymphedema with varying degrees of specificty and sensitivity depending on criteria set (Bland et al., 1993). The choice of criteria also affects the reported incidence of BCRL (Armer et al., 2005). As an approach for early detection and early treatment, arm volumes were measured prior to surgery in 196 women and at 3 month intervals after surgery (Stout Gergich et al.,2008). Using an increase in arm volume greater than 3% as criteria for lymphedema, they found that 43 (21.9%) exceeded the threshold by 6.9 months post-surgery. If these women then wore a compression garment for about 4 weeks, their increased arm volumes (83+/-119 ml)was reduced by 48+/-103 ml, which was sustained for 4.8+/-4.1 months of followup.