Objective assessment of reconstructed breast hardness using a durometer

Whether a durometer was suitable for objectively measuring reconstructed breast hardness was evaluated.

Subjects were 81 women who underwent expander-implant reconstructions following breast cancer ablation. Capsular contracture was evaluated with Baker grading. Capsular thickness was measured with T1-weighted MRI at the upper areola area. The durometer was placed on the upper areola. Multiple logistic regression analysis was performed to compare variables.

On Baker grading, 17 breasts were Baker grade I, 52 breasts were Baker grade II, 11 breasts were Baker grade III, and 1 breast was Baker grade IV. Mean capsular thickness on MRI was 1.1 (SD 0.4) mm with Baker grade I, 1.2 (SD 0.3) mm with Baker grade II, 1.4 (SD 0.4) mm with Baker grade III, and 1.9 mm with Baker grade IV. Mean durometer value was 0 with Baker grade I, 0.2 (SD 0.5) with Baker grade II, 2.0 (SD 1.7), with Baker grade III, and 8 with Baker grade IV. Baker grade IV was excluded from analysis because there was only one case. When Baker grade III was defined as positive for hardness, multiple logistic regression analysis showed that durometer value was associated with Baker grade III (p = 0.0005), but capsular thickness was not. On receiver operating characteristic curve analysis of the durometer value for Baker grade III, the optimal cutoff value was 0.5 (sensitivity 0.92, 1-specificity 0.17, area under the curve 0.92).

The durometer offers an objective index of hardness that might replace the subjective Baker grading. Further studies are needed to confirm the utility of this index.