Metal artifact reduction from reformatted projections for hip prostheses in multislice helical computed tomography: techniques and initial clinical results.
Metal artifact reduction from reformatted projections for hip prostheses in multislice helical computed tomography: techniques and initial clinical results.
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DOI：
10.1097/rli.0b013e3181b0a2f9
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发表时间：
2009-11
影响因子：
6.7
通讯作者：
McCollough CH
中科院分区：
文献类型：
--
作者：
Yu L;Li H;Mueller J;Kofler JM;Liu X;Primak AN;Fletcher JG;Guimaraes LS;Macedo T;McCollough CH
髋关节假体是最常见的金属植入物类型之一，在计算机断层扫描（CT）检查中可能会导致明显的伪影。本研究的目的是发展一种基于投影的方法来减少多层螺旋CT中髋关节假体引起的金属伪影。该方法是基于一个新的概念，重新格式化的投影，这是由组合的投影数据在相同的视角在整个纵向扫描范围。在每个重新格式化的投影图像上进行金属的检测和分割。基于Delaunay三角剖分的二维插值用于填充在重新格式化的投影中去除金属后留下的空隙。然后使用市售算法重建校正的数据。该方法的主要优点是，金属物体的检测和插值都是在存在整个金属区域的完整重新格式化投影上执行的，这对于长髋关节假体特别有用。对20例使用髋关节假体的临床腹部/骨盆检查进行了纠正和临床评价。与未校正图像相比，一些关键器官的整体图像质量和显著性显著改善：整体质量（P = 0.0024）;膀胱基底（P = 0.0027）和直肠（P = 0.0078）。膀胱底部的平均噪声水平从86.7HU降低到36.2HU。在20例病例中，17例放射科医生更喜欢校正图像的冠状面（13）或轴向（4）视图。提出了一种减少多层螺旋CT金属伪影的新方法。初步临床结果表明，该方法可以有效地减少金属植入物造成的伪影的情况下，单侧和双侧髋关节假体。
Hip prosthesis is one of the most common types of metal implants and can cause significant artifacts in computed tomography (CT) examinations. The purpose of this work was to develop a projection-based method for reducing metal artifacts caused by hip prostheses in multislice helical CT. The proposed method is based on a novel concept, reformatted projection, which is formed by combining the projection data at the same view angle over the full longitudinal scan range. Detection and segmentation of the metal were performed on each reformatted projection image. Two dimensional interpolation based on Delaunay triangulation was used to fill voids left after removal of the metal in the reformatted projection. The corrected data were then reconstructed using a commercially available algorithm. The main advantage of this method is that both the detection of the metal objects and the interpolations are performed on complete reformatted projections with the entire metal region present, which is particularly useful for long hip prostheses. Twenty clinical abdominal/pelvis exams with hip prostheses were corrected and clinically evaluated. The overall image quality and the conspicuity in some critical organs were significantly improved compared with the uncorrected images: overall quality (P = 0.0024); bladder base (P = 0.0027), and rectum (P = 0.0078). The average noise level in the bladder base was reduced from 86.7 HU to 36.2 HU. In 17 of 20 cases, the radiologists preferred either coronal (13) or axial (4) views of the corrected images. A novel method for reducing metal artifact in multislice helical CT was developed. Initial clinical results showed that the proposed method can effectively reduce the artifacts caused by metal implants for the cases of unilateral and bilateral hip prothesis.