Validity and Reliability of Three-dimensional Imaging to Measure Limb Volume: A Systematic Review

Introduction: Approximately 30% of women treated for breast cancer will develop lymphedema, yet early identification can prevent this occurrence. It is important to accurately and efficiently measure limb volume to identify pre-clinical lymphedema. Three-dimensional (3 D) imaging is emerging as a potential method to meet the need for accuracy and efficiency. The purpose of this review was to evaluate the psychometrics of 3 D imaging to measure limb volume. Methods: A systematic search of 4 databases was conducted for articles using 3 D imaging to measure limb volume. Articles were included that compared 3 D imaging to water displacement using human subjects, from 2000 to present. Data related to relevant psychometrics (validity, reliability, responsiveness) and patient populations were extracted from each article and analyzed. Risk of bias in study design was also assessed for each article. Results: The initial search of publications included 141 articles, 27 of which were selected based on the title and abstract. Only 13 articles were selected after full text review. Evidence from a preponderance of high-quality studies demonstrates that 3 D imaging is valid and reliable. Discussion: 3 D scanning can provide an accurate and efficient alternative means of measuring limb volume in breast cancer related lymphedema when compared to the reference standard of water displacement. Limitations to immediate clinical adoption include lack of information related to diagnostic accuracy and responsiveness, as well as a uniform definition of lymphedema

Validity of the Body Scan Scanner® and Structure Sensor to Measure Limb Volume in Healthy Adults

Purpose/Hypothesis: Secondary lymphedema is a chronic condition that can develop in approximately 30 percent of women treated for breast cancer. It is important to measure limb volume changes for early detection of lymphedema, when it is possible to reverse the swelling (stage 1). Common clinical measures carry concerns of infection control (water displacement), are time consuming (truncated cone calculation using circumferential measures), or expensive (perometry). Use of a portable 3D scanner addresses these concerns, but the validity is unknown. The purpose of this phase I study is to investigate the validity of the Body Scan Scanner to measure limb volume in healthy volunteers. Number of Subjects: A convenience sample of 4 female and 6 male adults with a mean age of 23 (range 22-25) without any medical conditions resulting in limb swelling participated. Materials and Methods: Participants underwent the measurement of limb volume bilaterally with 3D infrared scanning using the Body Scan Scanner®. The reference standard was water displacement. Descriptive statistics for age and BMI were calculated. Pearson’s r was used to correlate the water displacement and 3D scanned limb volume measurements. Results: The mean BMI of all participants was 22.78 (±3.65). The mean volume of the right limb was 1852 ml (±439) and 1872 ml (±131) for water displacement and 3D scanning respectively. The mean volume of the left limb was 1762 ml (±118) and 1823 ml (±117) for water displacement and 3D scanning respectively. Both the right and left limbs measurements were significantly correlated (p≤0.001); r=.996 and r=.991 respectively. Conclusions: The limb volume measurements taken with the 3D Body Scan Scanner are strongly correlated with the reference standard of water displacement for limb volume measures. Clinical Relevance: Portable 3D scanning shows promise to be an efficient and cost-effective method to measure limb volume clinically. Further research in individuals with breast cancer related lymphedema is needed