Reproducibility and day time bias correction of optoelectronic leg volumetry: a prospective cohort study

Abstract

BackgroundLeg edema is a common manifestation of various underlying pathologies. Reliable measurement tools are required to quantify edema and monitor therapeutic interventions. Aim of the present work was to investigate the reproducibility of optoelectronic leg volumetry over 3 weeks' time period and to eliminate daytime related within-individual variability.MethodsOptoelectronic leg volumetry was performed in 63 hairdressers (mean age 45 ± 16 years, 85.7% female) in standing position twice within a minute for each leg and repeated after 3 weeks. Both lower leg (legBD) and whole limb (limbBF) volumetry were analysed. Reproducibility was expressed as analytical and within-individual coefficients of variance (CVA, CVW), and as intra-class correlation coefficients (ICC).ResultsA total of 492 leg volume measurements were analysed. Both legBD and limbBF volumetry were highly reproducible with CVA of 0.5% and 0.7%, respectively. Within-individual reproducibility of legBD and limbBF volumetry over a three weeks' period was high (CVW 1.3% for both; ICC 0.99 for both). At both visits, the second measurement revealed a significantly higher volume compared to the first measurement with a mean increase of 7.3 ml ± 14.1 (0.33% ± 0.58%) for legBD and 30.1 ml ± 48.5 ml (0.52% ± 0.79%) for limbBF volume. A significant linear correlation between absolute and relative leg volume differences and the difference of exact day time of measurement between the two study visits was found (P < .001). A therefore determined time-correction formula permitted further improvement of CVW.ConclusionsLeg volume changes can be reliably assessed by optoelectronic leg volumetry at a single time point and over a 3 weeks' time period. However, volumetry results are biased by orthostatic and daytime-related volume changes. The bias for day-time related volume changes can be minimized by a time-correction formula.

Biological variation of established and novel biomarkers for atherosclerosis: Results from a prospective, parallel-group cohort study

“…Expressed differently, an ICC close to 1 signifies little variation within compared to the variation between subjects [41]. The ICCs reported here show a wide range from 0.19 for S100A8/A9 to 0.88 for oxLDL in healthy controls, with similar values found in PAD patients.…”

Limb Differences in the Therapeutic Effects of Complex Decongestive Therapy on Edema, Quality of Life, and Satisfaction in Lymphedema Patients

“…The measurements were obtained twice at each exam by another examiner, and these automatically calculated values (mL) were then averaged. Reproducibility of the Perometer has been confirmed by our institutions and by others [ 11 18 19 20 ].…”

“…Limb lymphedema volumes were measured using the electronic volumeter device (Perometer; Pero-System, Wuppertal, Germany), which is an optoelectronic instrument for measuring limb volume and circumferences [ 19 20 ]. The measurements were obtained twice at each exam by another examiner, and these automatically calculated values (mL) were then averaged.…”

Effectiveness of acupuncture for breast cancer related lymphedema: protocol for a single-blind, sham-controlled, randomized, multicenter trial

“…As pointed out above, perometer can easily and swiftly measure the volume of a participants’ limb with high reliability and minimal inter-operator variability compared with other conventional methods, such as volumeters (using a water displacement tank to measure volume) and tape measures (using a tape to measure limb circumference) [ 48 – 50 ], although the measurements from different methods are not interchangeable [ 51 ]. According to the data collected from patients and previous reports, the day to day variability in limb volumes is around 0.5 [ 52 ]. What is more, to better embody the real effect of acupuncture on BCRL, we use the ARLVR, a more reasonable and practical index that is calculated based on the surplus between the affected arm and the contralateral arm.…”