Filter wheel equalization in DSA: simulation results.
Filter wheel equalization in DSA: simulation results.
复制标题
DSA 中的滤光轮均衡：模拟结果。
DOI：
10.1118/1.597037
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发表时间：
1993
期刊：
影响因子：
3.8
通讯作者：
D. Levin
中科院分区：
文献类型：
--
作者：
J. Boone;G. Gardiner;D. Levin
数字减影血管造影（DSA）是一种有价值且常用的诊断技术，可以评估血管解剖和病理学。为了提高DSA的实用性和诊断性能，提出了一种滤光轮系统，它可以为DSA图像提供机械简单、快速适应和临床实用的射线照相均衡化。滤光轮均衡系统由一系列计算机驱动的滤光轮组成，安装在 X 射线管和准直器之间。每个轮子都有一个由衰减器材料制成的环形区域，该区域与 X 射线束相交，并在其上带有旋转变化的补偿图案。滤光轮的旋转在计算机控制下调制 X 射线场中的衰减器图案，其设计方式旨在增加图像中曝光不足区域的 X 射线曝光。具有八个轮子的系统有 10(19) 种可能的均衡模式。补偿图案在减影 DSA 图像中被移除。计算机模拟技术用于评估滤光轮系统的各种设计方案，并使用 191 个临床 DSA 掩模图像的数据库。对于滤光轮系统的实际实施，我们发现图像的平均信噪比提高了 23%。
Digital subtraction angiography (DSA) is a valuable and frequently used diagnostic technique which allows the evaluation of vascular anatomy and pathology. In order to improve the utility and diagnostic performance of DSA, a filter wheel system is presented which can provide mechanically simple, rapidly adaptable, and clinically practical radiographic equalization to DSA images. The filter wheel equalization system consists of a series of computer-driven filter wheels, mounted between the x-ray tube and collimator. Each wheel has an annular area of attenuator material which intersects the x-ray beam and carries a rotationally varying compensation pattern on it. Rotation of the filter wheel modulates the attenuator pattern in the x-ray field under computer control, in a manner designed to increase the x-ray exposure to underexposed areas in the image. A system with eight wheels has 10(19) possible equalization patterns. The compensation patterns are removed in the subtracted DSA images. Computer simulation techniques were used to evaluate various design scenarios for the filter wheel system, using a data base of 191 clinical DSA mask images. For a practical implementation of the filter wheel system, an improvement in the signal to noise ratio of 23%, averaged over the image, was found.