在DICOM中旋转图像方向(患者) [英] Rotate Image Orientation(Patient) in DICOM

问题描述

我从MRI采集中提取了3D表面，并且描述该表面的点的坐标是(我相信)相对于该系列第一幅图像的参考系统(我的意思是原点对应于Image位置(患者)和相对于图像方向(患者)的轴方向.我有另一组图像，这些图像具有不同的图像位置(患者)和不同的图像方向(患者)；我想旋转和平移从第一组图像中提取的表面，以使其与第二组图像完全匹配.

I have extracted a 3D surface from an MRI acquisition and the coordinates of the points describing this surface are (I believe) with respect to the reference system of the first image of the series (I mean that the origin corresponds to the Image Position(Patient) and the axes orientation to the Image Orientation(Patient)). I have another set of images with a different Image Position(Patient) and a different Image Orientation(Patient); I want to rotate and translate the surface extracted from the first set in order to have it match exactly the second set of images.

一旦找到正确的4x4矩阵，我就遇到了麻烦，一旦知道了，我便知道如何将其应用于我的表面.

I'm having trouble with finding the correct 4x4 matrix that would do the job, once I get it, I know how to apply it to my surface.

非常感谢您提供任何帮助.

Any kind of help would be greatly appreciated, thank you.

西蒙(Simon)

推荐答案

本页说明了如何根据DICOM标头中的几何信息形成转换矩阵.这些转换矩阵用于将体积坐标系(像素x，像素y，切片数)转换为患者/世界坐标系(以毫米为单位).

This page explains how to form a transformation matrix from the geometry information in the DICOM headers. These transformation matrices are used to transform from the volume coordinate system (pixel-x, pixel-y, slice number) to the patient/world coordinate system (in millimeters).

从体积1转换为体积2的基本思想是从体积1转换为患者坐标，并从患者坐标转换为体积2坐标系.将这两个矩阵相乘，就可以将矩阵直接从体积1转换为体积2.

The basic idea to transform from volume 1 to volume 2 is to tranform from volume 1 to patient coordinates and from patient coordinates to volume 2 coordinate system. Multiplying both matrices yields the matrix to transform directly from volume 1 to volume 2.

警告:显然，不能保证v1中的每个坐标都与v2中的坐标相匹配，即，堆栈的大小和/或位置可能不同.

Caution: Obviously, there can be no guarantee that every coordinate in v1 matches a coordinate in v2, i.e. the stacks may have different size and/or position.

所以你有

M1-从体积1转换为世界坐标系的矩阵，以及M2-从第2卷转换为世界坐标系的矩阵

M1 - the matrix to transform from volume 1 to the world coordinate system and M2 - the matrix to transform from volume 2 to the world coordinate system

然后

M1 *(M2 ^(-1))是将位置矢量从体积1转换为体积2的矩阵(输入和输出是pixel-x，pixel-y，slice number)

M1 * (M2^(-1)) is the matrix to transform a position vector from volume 1 to volume 2 (input and output is pixel-x, pixel-y, slice number)

和

M2 *(M1 ^(-1))是将位置矢量从体积1转换为体积2的矩阵(输入和输出是pixel-x，pixel-y，slice number)

M2 * (M1^(-1)) is the matrix to transform a position vector from volume 1 to volume 2 (input and output is pixel-x, pixel-y, slice number)

这篇关于在DICOM中旋转图像方向(患者)的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！