Bravin Alberto, Keyriläinen Jani, Fernández Manuel, Fiedler Stefan, Nemoz Christian, Karjalainen-Lindsberg Marja-Liisa, Tenhunen Mikko, Virkkunen Pekka, Leidenius Marjut, von Smitten Karl, Sipilä Petri, Suortti Pekka
ID17, European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex, France.
Phys Med Biol. 2007 Apr 21;52(8):2197-211. doi: 10.1088/0031-9155/52/8/011. Epub 2007 Mar 29.
The aim of this study was to introduce high-resolution computed tomography (CT) of breast tumours using the diffraction-enhanced x-ray imaging (DEI) technique and to compare results with radiological and histo-pathological examinations. X-ray CT images of tumour-bearing breast tissue samples were acquired by monochromatic synchrotron radiation (SR). Due to the narrow beam and a large sample-to-detector distance scattering is rejected in the absorption contrast images (SR-CT). Large contrast enhancement is achieved by the use of the DEI-CT method, where the effects of refraction and scatter rejection are analysed by crystal optics. Clinical mammograms and CT images were recorded as reference material for a radiological examination. Three malignant and benign samples were studied in detail. Their radiographs were compared with optical images of stained histological sections. The DEI-CT images map accurately the morphology of the samples, including collagen strands and micro-calcifications of dimensions less than 0.1 mm. Histo-pathological examination and reading of the radiographs were done independently, and the conclusions were in general agreement. High-resolution DEI-CT images show strong contrast and permit visualization of details invisible in clinical radiographs. The radiation dose may be reduced by an order of magnitude without compromising image quality, which would make possible clinical in vivo DEI-CT with future compact SR sources.
本研究的目的是采用衍射增强X射线成像（DEI）技术对乳腺肿瘤进行高分辨率计算机断层扫描（CT），并将结果与放射学和组织病理学检查结果进行比较。通过单色同步辐射（SR）获取荷瘤乳腺组织样本的X射线CT图像。由于光束狭窄且样品到探测器的距离较大，吸收对比图像（SR-CT）中的散射被抑制。通过使用DEI-CT方法可实现较大的对比度增强，其中通过晶体光学分析折射和散射抑制的效果。记录临床乳房X线照片和CT图像作为放射学检查的参考材料。对三个恶性和良性样本进行了详细研究。将它们的射线照片与染色组织切片的光学图像进行比较。DEI-CT图像准确地描绘了样本的形态，包括胶原纤维束和尺寸小于0.1毫米的微钙化。组织病理学检查和射线照片的解读是独立进行的，结论总体一致。高分辨率DEI-CT图像显示出强烈的对比度，能够显示临床射线照片中不可见的细节。在不影响图像质量的情况下，辐射剂量可降低一个数量级，这将使未来使用紧凑型SR源进行临床体内DEI-CT成为可能。
