几何模型匹配乳腺头足位与内外斜位X线片所示病灶

目的 观察几何模型（GM）匹配乳腺头足（CC）位与内外斜（MLO）位X线片所示病灶的价值。方法 回顾性分析493例接受乳腺CC位和MLO位X线摄影的乳腺病灶患者，共598个乳腺病灶，包括499个钙化灶和99个肿块。构建GM用于匹配CC与MLO位片所示乳腺病灶，再以环形法（AB）和直线法（SS）进行对比，分别计算匹配误差，包括GM匹配误差、AB径向误差及SS轴向误差；分析GM对CC及MLO位图像中同一病灶的匹配性能，评价其应用价值。结果 GM对乳腺钙化灶和肿块的匹配误差分别为2.85（1.45，5.08）及3.70（1.35，6.25） mm，差异无统计学意义（Z=－1.344，P=0.179）。对乳腺上部病灶，AB匹配的径向误差和SS匹配的轴向误差均大于下部病灶（P均<0.001）；对乳腺外侧病灶，AB的径向误差和SS的轴向误差均大于内侧病灶（P均<0.05）。GM、AB及SS间匹配误差整体差异有统计学意义（H=93.012，P<0.001）；两两比较差异均有统计学意义（P均<0.05），GM匹配性能明显优于AB和SS。GM匹配误差与摄片时乳腺压迫厚度无明显相关性。结论 GM用于匹配乳腺CC位与MLO位X线片所示病灶较具价值。

Geometric model for matching breast lesions on craniocaudal and mediolateral oblique mammograms

Objective To observe the value of geometric model (GM) for matching breast lesions on craniocaudal (CC) and mediolateral oblique (MLO) mammograms. Methods Data of 493 patients with 499 breast calcifications and 99 breast masses who underwent mammography of CC and MLO views were retrospectively analyzed. GM model was constructed to match breast lesions on CC and MLO mammograms. Then the annular band (AB) and straight strip (SS) were also performed for matching. The matching errors, including GM matching error, AB radial error and SS axial error were calculated, the matching performances of GM for the same lesion on CC and MLO mammograms were compared, and the application value of GM was analyzed. Results GM matching error of breast calcifications and masses was 2.85 (1.45, 5.08) and 3.70 (1.35, 6.25) mm, respectively, with no significant difference (Z=-1.344, P=0.179). AB radial error and SS axial error of the upper breast lesions were greater than those of the lower breast lesions (both P<0.001), and of the lateral breast lesions were greater than those of the medial breast lesions (both P<0.05). Significant difference of matching error existed among GM, AB and SS (H=93.012, P<0.001) and between each 2 methods (all P<0.05), and the matching performance of GM was better than AB and SS. There was no significant correlation between GM matching error and the thickness of compressed breast on mammograms. Conclusion GM was valuable for matching breast lesions on CC and MLO mammograms.