Dual-energy X-ray bone mineral density detection method based on moving least square algorithm

Abstract

The invention relates to a dual-energy X-ray bone mineral density detection method based on a moving least square algorithm, which comprises the following steps: acquiring detection data of a motif under high-energy and low-energy X-rays of a photon counting detector, and carrying out preprocessing including denoising; the incident energy of the high-energy X-ray and the low-energy X-ray is obtained; calculating to obtain high and low energy attenuation values; performing grid division according to the thickness of the die body; after a weight function of a moving least square algorithm is determined, dividing an influence domain radius by taking a target node as a center in each grid, traversing each high-energy and low-energy attenuation value data point in a spatial domain, and setting a variable step length in the influence domain; obtaining a final fitting relationship by adopting a least square algorithm, and obtaining a die body thickness-high and low energy attenuation value fitting curved surface; a bone mineral density ROI area needing to be measured is determined, the corresponding motif thickness is obtained through calculation, and the product of the motif thickness and the motif density is the bone mineral density value of the corresponding part. According to the method, the problems of fitting smoothness and localization are solved.

Description

technical field [0001] The invention belongs to the technical field of medical devices, and in particular relates to the field of application of dual-energy X-ray bone density measurement. Background technique [0002] Osteoporosis is one of the six frequently occurring diseases in the world. However, the disease has no obvious symptoms in the early stage, and people will not pay attention to it, so how to prevent and diagnose osteoporosis is very important. Bone density measurement is an important method currently used to evaluate bone loss and diagnose osteoporosis. The human skeleton is composed of dense cortical bone and many spongy cancellous bones in the bone marrow cavity. Its main component is hydroxyapatite, which mainly exists in calcium and phosphorus. Osteoporosis is the loss of calcium and phosphorus, which leads to a decrease in bone mineral content. The main medical measure of bone density is the density of hydroxyapatite. [0003] Dual-energy X-ray absorpt...

AI Technical Summary

Problems solved by technology

Polynomial fitting has a large amount of calculations, and the calculation process is cumbersome, and the requirements for fitting coefficients are high, otherwise it is difficult to achieve the best fitting surface and it is easy to increase the error

[0006] The dual-energy X-ray bone densitometer based on photon counting detector is a photon counting detector using CdZnTe crystal. Under ideal conditions, the photon counting detector can make full use of X-ray energy spectrum information, effectively improve image quality, and obtain material Composition information can enhance soft tissue contrast, but due to the immature manufacturing process, photon counting detectors are prone to dead spots on the edge of the module, and there are inhomogeneities between pixel units, which are easy to affect each other. The error of traditional algorithm has great influence

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