Standardised measurements used to order compression garments can be used to calculate arm volumes to evaluate lymphoedema treatment.

Abstract Lymphoedema treatment outcome can be evaluated by calculating estimated limb volumes directly by water displacement (plethysmography; PG), or indirectly by circumference measurements (CM) and using the formula for a truncated cone. This study assessed the correlation between PG and circumference volume measurements to assess whether the correlation is acceptable, and if circumference measurements can be used to accurately assess arm volume. Ten women with unilateral lymphoedema after breast cancer treatment with a mean age of 66 (range 50-83) years volunteered for arm volume estimates by PG and circumference measurements. The coefficient of variation (CV%) for all methods was calculated. Two Excel-based formulae of the truncated cone were developed; one for fixed 4-cm intervals leading to 10 volume segments (CM-10-VS), and one for varying intervals leading to four volume segments (CM-4-VS). The CV% was 0.609% for PG, 0.628% for CM-10-VS, and 0.632% for CM-4-VS. As expected, PG generated a significantly larger volume of both arms because it includes the hand. The difference between CM-10-VS and CM-4-VS measurements was not significant. All three measurement methods showed a high coefficient of correlation (0.813-0.915), and a high coefficient of regression (0.863-1.089). The excess volume, which is used to determine treatment outcome, showed the respective values of 0.932-0.978 and 0.963-1.020, respectively. Using circumference measurements identical to those used when ordering made-to-measure compression garments speeds up volume measurements and can be used safely to evaluate lymphoedema treatment outcome