J reconstr Microsurg 2018; 34(01): 029-034
DOI: 10.1055/s-0037-1606267
Original Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Agreement between Perometry and Sequential Arm Circumference Measurements in Objective Determination of Arm Volume

Bernardo Nogueira Batista
1  Breast Unit, Hospital Sírio Libanês, São Paulo, Brazil
Jaqueline Munaretto Timm Baiocchi
2  Department of Cutaneous Oncology, AC Camargo Cancer Center, São Paulo, Brazil
Larissa Louise Campanholi
2  Department of Cutaneous Oncology, AC Camargo Cancer Center, São Paulo, Brazil
Anke Bergmann
3  Molecular Carcinogenesis Program, Instituto Nacional do Câncer – INCA/MS, Rio de Janeiro, Brazil
João Pedreira Duprat
2  Department of Cutaneous Oncology, AC Camargo Cancer Center, São Paulo, Brazil
› Author Affiliations
Further Information

Publication History

28 February 2017

11 July 2017

Publication Date:
25 August 2017 (eFirst)


Background Limb circumference measurements (CM) and perometry are the preferred methods for objectively measuring arm volume in lymphedema surgery research. Understanding the measurement bias involved in these measuring systems is important to properly interpret and compare studies and their results.

Methods Arm volumes from 91 patients were measured using sequential girths and the truncated cone formula (CM) and with the use of an automated perometer (perometry). The absolute volume of the largest arm (V), the volume difference between the arms (VD), and the relative difference between them (percentage of excess volume [PEV]) were calculated with both methods. The agreement between methods was assessed by the Pearson's correlation test and the Bland–Altman's method.

Results Correlations were strong for V (r = 0.99), VD (r = 88), and PEV (r = 0.86). Volumes measured by perometry were, on average, 10.6 mL smaller than volumes calculated from CM, while their limits of agreement (LOA) ranged from −202 to 181 mL. The LOA represents the range we could expect the arm volumes measured with the two methods to differ by chance alone, 95% of the times. For VD, LOA was −101 to 141 mL, with a mean difference of 19.9 mL, while PEV had a mean difference of 0.9%, with LOA ranging from −5 to 6.8%.

Conclusion There is considerable measurement error between arm volume estimated by perometry and by CM. Volumes calculated with these methods should be compared with caution. Furthermore, we observed an increasingly relevant measurement bias in outcomes that are mathematically derived from arm volumes.