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Background There are challenges related to the accurate and efficient measurement of lymphedema in people with breast cancer. The LymphaTech 3D Imaging System (LymphaTech, Atlanta, GA, USA) is a mobile, noninvasive platform that provides limb geometry measurements. Objective The objective of this study was to estimate the reliability and validity of the LymphaTech for measuring arm volume in the context of women seeking care in a specialty breast cancer rehabilitation clinic. Design This was a cross-sectional reliability and convergent validity study. Methods People who had stage I to IV breast cancer with lymphedema or were at risk for it were included. Arm volume was measured in 66 participants using the LymphaTech and perometer methods. Test-retest reliability for a single measure, limb volume difference, and agreement between methods was analyzed for 30 participants. A method-comparison analysis was also used to assess convergent validity between methods. Results Both LymphaTech and perometer methods displayed intraclass correlation coefficients (ICCs) of ≥0.99. The standard errors of measurement for the LymphaTech and length-matched perometer measurements were nearly identical. Similar intraclass correlation coefficients (0.97) and standard errors of measurement (38.0–40.7 mL) were obtained for the between-limb volume difference for both methods. The convergent validity analyses demonstrated no systematic difference between methods. Limitations The sample size was not based on a formal sample size calculation. LymphaTech measurements included interrater variance, and perometer measurements contained intrarater variance. Conclusions The LymphaTech had excellent test-retest reliability, and convergent validity was supported. This technology is efficient and portable and has a potential role in prospective surveillance and management of lymphedema in clinical, research, and home settings.

Abstract Background Lymphedema is a common complication of breast cancer treatment that affects one in five breast cancer survivors, yet there is no reliable method to detect lymphedema in the subclinical range. The objective of this study was to determine the feasibility and reliability of using an infrared 3D scanning device (ISD) as a peri-operative limb volume measurement tool. Methods Fifteen patients were analyzed based on inclusion criteria. Peri-operative measurements were obtained using tape measure and an ISD. Volumes were calculated using a standard algorithm for tape measure and a custom algorithm for ISD measurements. Linear regression models were used to assess ISD and tape measurement volume and circumference correlation. One-way ANOVA was used to compare change in percent difference at set time points post-operatively (2–3 weeks, 4–6 weeks, and 7–12 weeks) for both ISD and tape measure. t tests for unequal variances with the Bonferroni correction were performed among these groups. Results There is a positive linear correlation (R2 = 0.8518) between absolute volume measurements by the ISD and tape measure. Analyses over 2–10 weeks post-operatively showed that the ISD was able to detect volume changes in both the unaffected and the affected arm. Furthermore, the affected arm tended to have a greater increase in volume in the majority of patients, indicating these patients could be at risk for lymphedema. Conclusions Technology utilizing infrared 3D scanners can reliably measure limb volume pre- and post-treatment similarly to tape measure in a small sample of patients. Further research using 3D scanning technology with a longer follow up is warranted.

Competition models may be used by ecologists as basic guidelines in analyzing issues that contribute to the decline of species population. To be used for that purpose, a mathematical model must be prudently parameterized. Therefore, this paper examines the effects of interference competition by lions with human–related mortality to the population dynamics of African wild dogs. The model was carefully parameterized and validated with estimated data by employing the theory of basic reproduction number and by running the sensitivity analysis. Numerical simulation of the model was executed by using MATLAB to explore the outcome of certain key parameters when changes are applied on them.