Bick U, Giger M L, Schmidt R A, Nishikawa R M, Doi K
Department of Radiology, University of Muenster, Germany.
Radiographics. 1996 Nov;16(6):1403-11. doi: 10.1148/radiographics.16.6.8946544.
When digital mammograms are viewed on video displays, evaluation of the skin and subcutaneous tissue is often difficult and may require special window settings. An algorithm has been developed for selective enhancement (ie, density correction) of the dark peripheral portions of the breast on mammograms. After an automated segmentation of the digital mammogram and identification of the skin line, a fitted enhancement curve is generated to selectively enhance all pixels within a certain distance from the skin to match the density of the center part of the breast. After enhancement, skin and breast parenchyma can be evaluated simultaneously without the need for different window settings. When tested on a set of 400 digitized mammograms, the density correction algorithm significantly (P < .0001) increased the maximum area of breast tissue visualized simultaneously at window width settings of 0.5-2.0 delta OD (optical density). Artifacts interfering with interpretation were observed in less than 1%. The algorithm for correcting the density of peripheral breast tissue substantially facilitates and improves the display of digital mammograms and thus will be a valuable component of an integrated workstation for computer-aided diagnosis in mammography.
当在视频显示器上查看数字乳腺X线照片时，对皮肤和皮下组织的评估通常很困难，可能需要特殊的窗口设置。已经开发出一种算法，用于对乳腺X线照片上乳房的深色周边部分进行选择性增强（即密度校正）。在对数字乳腺X线照片进行自动分割并识别出皮肤线后，生成一条拟合的增强曲线，以选择性增强距皮肤一定距离内的所有像素，使其与乳房中心部分的密度相匹配。增强后，无需不同的窗口设置即可同时评估皮肤和乳腺实质。在一组400张数字化乳腺X线照片上进行测试时，密度校正算法在0.5 - 2.0ΔOD（光密度）的窗口宽度设置下，显著（P <.0001）增加了同时可视化的乳腺组织的最大面积。观察到干扰解读的伪影不到1%。校正乳腺周边组织密度的算法极大地促进并改善了数字乳腺X线照片的显示，因此将成为乳腺X线摄影计算机辅助诊断集成工作站的一个有价值的组成部分。
