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我是处理 DICOM 图像远离其原生制造商软件的新手。我正在尝试将一组重建的横轴切片中的 PET 图像 dicomread 到 MatLab 中。我的目标是做一些简单的分割,最后确定分割中的最大和最小像素值。但是,我无法将存储的值转换为在本机系统上看到的值。

图像作为 int16 类加载到 MatLab 中。无论我从系列中加载哪个切片,最大像素值始终为 32767。我通过查看他们本机系统上的图像知道每个切片中的最大像素值是不同的。

我检查了重新缩放值和重新缩放截距值,重新缩放关系似乎是线性的。我应该做另一个更正吗?我假设所有其他校正(例如衰减、散射和随机)都是在重建过程中进行的。

任何帮助将不胜感激(希望我遗漏了一些简单的东西!)。我已经发布了从下面的标题中检索到的 DICOM 信息(不要担心,图像是幻影,因此没有患者识别数据)。

问候,

罗斯

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2 回答 2

1

我在 mammo 工作,没有 PET 的经验,所以我在这里说的有点少。

最大像素值为 32767,即 2 的 15 次方减 1。重新缩放斜率不重要吗?

RescaleSlope: 0.3555

据推测,这可能因每个切片而异,并且像素值应乘以该值(也应添加截距,但该值为零)。

于 2013-08-06T08:50:41.607 回答
1

在主要的扫描仪制造商(西门子、通用电气、飞利浦)中,我在使用通用电气 PET 相机时只遇到过逐片的 RescaleSlope 值。但是,检查 RescaleSlope 和 RescaleIntercept 总是一个好主意。QIBA FDG-PET 工作组收集了一系列建议以及直接从 DICOM 数据计算 SUV 的伪代码。

于 2014-01-30T16:36:38.893 回答