Method and device for reducing metal artifacts in medical images

Abstract

The invention provides a method and a device for reducing metal artifacts in medical images, wherein the same fault of medical images comprises artifacts comprises artifacts generated by large metal objects and small metal objects with different sizes. The method is used for processing artifacts generated by the large metal objects and the small metal objects in the same fault image by different methods. According to the invention, the small metal objects can be automatically excluded out of the algorithm processing, and meanwhile the artifacts caused by the large metal objects can be removed as much as possible.

Description

technical field [0001] The present invention relates generally to image processing, and more particularly to methods and apparatus for reducing metal artifacts in medical images. Background technique [0002] During radiotherapy, on the one hand, for patients with metal implants (such as dentures, alloy femoral heads), serious shadow artifacts will be produced in the obtained medical images (eg CT images). This condition is very common in patients with brain or prostate tumors. On the other hand, doctors usually use small metal markers to localize tumors for radiotherapy, which also introduces metal artifacts. In the radiotherapy of tumors, the accuracy of the tumor location provided by computed tomography (CT) images is very important, so it is necessary to reduce the influence of metal artifacts. [0003] figure 1 is a flowchart of a prior art MAR method 100 . [0004] The method starts at step 110, where a pre-reconstruction is first performed on the CT image. This p...

AI Technical Summary

Problems solved by technology

from Figure 3B and Figure 3C It can be seen that the channels with metal projections from BFP cannot cover all the real channels with metal projections

Therefore, there are residual metal artifacts in the reconstruction, such as Figure 3C shown

[0015] Third, the interpolation in the projection data correction (step 140) will result in data loss for small metals, which will introduce additional artifacts

Then, severe artifacts appear along the direction connecting small and large metals, such as Figure 4C shown

[0016] Fourth, in the metal backfill step (step 160), a single smoothing radius does not guarantee good enough image quality for both small and large metals

[0018] Therefore, the MAR method in current RT cannot guarantee that small metals are well preserved while large metals have smooth edges

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