Method for removing splicing artifacts in stepping shaft scanning CT reconstruction and electronic medium

Abstract

The invention discloses a method for removing splicing artifacts in stepping shaft scanning CT reconstruction and an electronic medium, and is applied to the technical field of image processing. The method comprises the following steps: carrying out CT scanning to obtain projection data; carrying out image reconstruction on all the projection data by adopting a cone beam reconstruction algorithm;carrying out nonlinear filtering on all the reconstructed images, and outputting filtered images; obtaining a common P-layer image of a boundary region between the kth scanning and the (k + 1)th scanning and the vicinity of the boundary region, and calculating a distance weight and an organization structure weight of each image, performing image correction on the P-layer image according to the distance weight and the organization structure weight, and removing splicing artifacts until image correction of all data of N times of CT scanning is completed, thereby obtaining a final image of whichthe splicing artifacts are removed. According to the method, image correction is carried out on the boundary area image of stepping shaft scanning, the splicing artifacts of the boundary area are removed, the calculation efficiency is high, the image quality is improved, extra hardware assistance is not needed, and clinical requirements can be met.

Description

technical field [0001] The invention relates to the technical field of image processing, in particular to a method and an electronic medium for removing stitching artifacts in stepping axis-scan CT reconstruction. Background technique [0002] The CT medical imaging system has made great progress since its invention in the 1970s, and the scanning speed has changed from a few minutes at the beginning to 0.2 seconds now. The number of detector rows has also changed from single row and double row at the beginning to the current 64 rows, 128 rows, and even 256 rows. The change is not only the upgrade of the system hardware, but also the system's image reconstruction technology has brought about revolutionary changes. Since the initial CT system has only one row of detectors, the X-ray beam is a fan beam, and the reconstruction techniques used are also two-dimensional fan beam reconstruction techniques. Because only one layer can be scanned at a time, the entire scan takes a lo...

AI Technical Summary

Problems solved by technology

The main reason for this is that the reconstruction error is proportional to the square of the cone angle (proportional to the number of detector rows), and as the number of detector rows increases, it will bring a large error

In addition to the cone angle, other factors such as beam hardening, Z-axis sampling, partial volume effects, etc. can also cause image inhomogeneity and artifacts

The inhomogeneity of these image quality can easily produce artifacts near the junction area of ​​the step scan, resulting in the image not meeting the requirements of clinical diagnosis

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