In vivo measurement of breast skin elasticity and breast skin thickness

Background: The mechanical properties of the breast skin play an important role in explaining the changes associated with radiotherapy, tissue expansion, and breast reconstruction surgery. Quantitative measurement of mechanical properties of breast skin is essential for surgical preplanning and outcome prediction. We have measured the skin elasticity properties and skin thickness of the breast using noninvasive methods. Methods: The DermaLab suction cup and the DermaScanC ultrasound were used to measure the modulus of elasticity and the skin thickness, respectively. Measurements were taken in 16 different locations on the breast in 23 female patients, also with patients in supine and upright position. Different analytical models (plate, membrane, large deformation) that can represent the experiment were studied to extract the elasticity modulus. Results: The average modulus of breast skin elasticity found was 344 +/- 88 kPa (Mean +/- SD) with 95% confidence interval being 306-382 kPa. The range of the modulus was 195480 kPa. The average thickness of breast skin was 1.55 +/- 0.25 mm with a range of 0.83-2.4 mm. Conclusions: Regional variations of breast skin elasticity properties and breast skin thickness were observed. No direct correlations of biomechanical properties with age or breast thickness were observed. No significant difference was observed in the elasticity modulus between the supine and upright patient positions.