Department of Breast Surgery, The Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey, SM2 5PT, UK.
Department of Statistics, The Royal Marsden NHS Foundation Trust, Sutton, UK.
Breast Cancer Res Treat. 2018 Sep;171(2):391-398. doi: 10.1007/s10549-018-4843-6. Epub 2018 Jun 5.
Three-dimensional surface imaging (3D-SI) of the breasts enables the measurement of breast volume and shape symmetry. If these measurements were sufficiently accurate and repeatable, they could be used in planning oncological breast surgery and as an objective measure of aesthetic outcome. The aim of this study was to validate the measurements of breast volume and symmetry provided by the Vectra XT imaging system.
To validate measurements, breast phantom models of true volume between 100 and 1000 cm were constructed and varying amounts removed to mimic breast tissue 'resections'. The volumes of the phantoms were measured using 3D-SI by two observers and compared to a gold standard. For intra-observer repeatability and inter-observer reproducibility in vivo, 16 patients who had undergone oncological breast surgery had breast volume and symmetry measured three times by two observers.
A mean relative difference of 2.17 and 2.28% for observer 1 and 2 respectively was seen in the phantom measurements compared to the gold standard (n = 45, Bland Altman agreement). Intra-observer variation over ten repeated measurements demonstrated mean coefficients of variation (CV) of 0.58 and 0.49%, respectively. The inter-observer variation demonstrated a mean relative difference of 0.11% between the two observers. In patients, intra-observer variation over three repeated volume measurements for each observer was 3.9 and 3.8% (mean CV); the mean relative difference between observers was 5.78%. For three repeated shape symmetry measurements using RMS projection difference between the two breasts, the intra-observer variations were 8 and 14% (mean CV), the mean relative difference between observers was 0.43 mm for average symmetry values that ranged from about 3.5 to 15.5 mm.
This first validation of breast volume and shape symmetry measurements using the Vectra XT 3D-SI system suggests that these measurements have the potential to assist in pre-operative planning and also as a measure of aesthetic outcome.
乳房三维表面成像（3D-SI）可用于测量乳房体积和形状对称性。如果这些测量足够准确且可重复，它们可用于规划肿瘤乳房手术，并作为美学结果的客观衡量标准。本研究的目的是验证 Vectra XT 成像系统提供的乳房体积和对称性测量。
为了验证测量，构建了真实体积在 100 至 1000cm 之间的乳房模型，并去除不同量的组织以模拟乳房组织“切除”。使用 3D-SI 由两名观察者测量模型的体积，并与金标准进行比较。为了评估观察者内的重复性和观察者间的可重复性，对 16 名接受过肿瘤乳房手术的患者进行了三次由两名观察者进行的乳房体积和对称性测量。
与金标准（n=45，Bland Altman 一致性）相比，观察者 1 和 2 在模型测量中的平均相对差异分别为 2.17%和 2.28%。十次重复测量的观察者内变异性显示出分别为 0.58%和 0.49%的平均变异系数（CV）。观察者间的变异性显示出两名观察者之间的平均相对差异为 0.11%。在患者中，每位观察者的三次重复体积测量的观察者内变异性为 3.9%和 3.8%（平均 CV）；观察者之间的平均相对差异为 5.78%。对于使用两个乳房之间的 RMS 投影差的三次重复形状对称性测量，观察者内变异性分别为 8%和 14%（平均 CV），观察者之间的平均相对差异为 0.43mm，平均对称值范围约为 3.5 至 15.5mm。
这是首次使用 Vectra XT 3D-SI 系统验证乳房体积和形状对称性测量，表明这些测量有可能有助于术前规划，并作为美学结果的衡量标准。
