阅读说明：本技术 利用MicroCT扫描肿瘤转移骨破坏3D重构的实验方法 (Experimental method for 3D reconstruction of metastatic bone destruction of tumor by using MicroCT scanning ) 是由 翁国忠 李秋芳 韦围 于 2021-09-01 设计创作，主要内容包括：本发明涉及显现X成像技术领域,且公开了利用MicroCT扫描肿瘤转移骨破坏3D重构的实验方法,所述方法包括以下步骤,S1、将实验所用骨质破坏的小白鼠放入扫描管中；S2、采用MicroCT进行扫描全程,在描述全程中扫描管实现全位置间断移动,将各个角度的区域重建在扫描框中,详细计算分段重建各个扫描框中对应的投影图像的信息,高效实现各个角度的投影；S3、调整扫描管至所采集骨质破坏部分的分段重建区域的最上段,依次扫描每个分段部分,对每个分段进行重建处理。该利用MicroCT扫描肿瘤转移骨破坏3D重构的实验方法,保证在对肿瘤转移骨破坏的重构更加精准的定位到三维的重构中,可以明细的了解到肿瘤转移骨破坏的具体情况,也方便后续进行深层次的试验研究。(The invention relates to the technical field of X-ray visualization and discloses an experimental method for 3D reconstruction of metastatic bone destruction of tumor by using MicroCT scanning, which comprises the following steps of S1, placing a white mouse with damaged bone used for experiment into a scanning tube; s2, carrying out the whole scanning process by adopting the MicroCT, realizing the all-position intermittent movement of the scanning tube in the whole description process, reconstructing the area of each angle in a scanning frame, calculating the information of the corresponding projection image in each scanning frame in detail and reconstructing in a segmented manner, and efficiently realizing the projection of each angle; and S3, adjusting the scanning tube to the uppermost segment of the segmented reconstruction region of the collected bone destruction part, scanning each segmented part in turn, and performing reconstruction processing on each segment. According to the experimental method for 3D reconstruction by scanning tumor metastasis bone destruction through MicroCT, the specific situation of the tumor metastasis bone destruction can be known in detail in the process of more accurately positioning the reconstruction of the tumor metastasis bone destruction to three-dimensional reconstruction, and the follow-up deep experimental study is facilitated.)

1. An experimental method for 3D reconstruction of metastatic bone destruction of tumor by using MicroCT scanning is characterized in that: the method comprises the following steps of,

s1, placing the white mouse with damaged bones into a scanning tube after anesthesia treatment;

s2, carrying out the whole scanning process by adopting the MicroCT, realizing the all-position intermittent movement of the scanning tube in the whole description process, reconstructing the area of each angle in a scanning frame, calculating the information of the corresponding projection image in each scanning frame in detail and reconstructing in a segmented manner, and efficiently realizing the projection of each angle;

s3, adjusting the scanning tube to the uppermost segment of the segmented reconstruction area of the collected bone destruction part, scanning each segmented part in sequence, and performing reconstruction processing on each segment to finally obtain a 3D reconstructed comprehensive tomogram of the bone destruction;

s4, performing preliminary analysis on the two-dimensional image data obtained by scanning by using a VMS system, Xming and PuTTY _ V0.63 software of the uCT-100, and setting different thresholds for the parts of the white mouse with bone destruction respectively, thereby realizing 3D reconstruction of the bone destruction through a VMS system program.

2. The experimental method for 3D reconstruction of metastatic bone destruction by MicroCT scanning according to claim 1, wherein: the scanning parameters of the MicroCT are as follows: kilovolt peak 90kvp, current 210uA, resolution 48.9um, exposure time 350 ms.

3. The experimental method for 3D reconstruction of metastatic bone destruction by MicroCT scanning according to claim 1, wherein: the method also comprises the step of carrying out initialization work by using a MicroCT imaging system device for judging the identification of the initial position and the final position of the white rat bone fracture.

4. The experimental method for 3D reconstruction of metastatic bone destruction by MicroCT scanning according to claim 1, wherein: before the white mouse in the scanning tube is scanned, the scanning tube is positioned at the origin in the vertical direction, the voltage and the current suitable for an object are adjusted, the resolution of an acquired image is set, and the frame rate of the image acquisition is set.

5. The experimental method for 3D reconstruction of metastatic bone destruction by MicroCT scanning according to claim 1, wherein: the CGTS-RB NPs were injected prior to scanning the mice.

6. The experimental method for 3D reconstruction of metastatic bone destruction by MicroCT scanning according to claim 1, wherein: in the step S2, the amplitude of the movement of the scanning tube to realize the full-position discontinuity is between 0 and 5 degrees, and the area to be tumor metastasis bone destruction is identified on the projection image of the whole white mouse.

7. The experimental method for 3D reconstruction of metastatic bone destruction by MicroCT scanning according to claim 1, wherein: the method step S3 specifies a reconstruction region scan frame size of 600 pixels, and if the selected region is larger than 600 pixels, the selected reconstruction region is set to an integer multiple of 600.

8. The experimental method for 3D reconstruction of metastatic bone destruction by MicroCT scanning according to claim 1, wherein: a CCD detector is arranged outside the MicroCT scanning, and the CCD detector and the X-ray source are the same in center height.

9. The experimental method for 3D reconstruction of metastatic bone destruction by MicroCT scanning according to claim 1, wherein: the scanning tube moves in the transverse direction to the maximum distance which is out of the visual field range of the CCD detector.

Technical Field

The invention relates to the technical field of X-ray visualization, in particular to an experimental method for tumor metastasis bone destruction 3D reconstruction by using MicroCT scanning.

Background

Micro-CT, also known as Micro CT, microfocus CT or Micro CT. The micro-focus X-ray bulb tube different from common clinical CT is used in scanning imaging analysis of small live animal or hard tissue and soft tissue, and has resolution as high as several microns, good microscopic effect and scanning layer thickness as high as 10 microns. By the Micro-CT technology, morphological characteristics of relevant tissues in living animals can be dynamically analyzed, three-dimensional reconstruction, bone morphological analysis and the like of the tissues can be performed on the basis of sample scanning, and meanwhile, high-level processing of images, mechanical analysis and other relevant analysis can be performed through software.

The basic structure of Micro CT is divided into three parts, namely a Micro-focus X-ray source, an object stage and a high-resolution imaging plate. During the imaging process, the X-ray source continuously generates cone-beam X-rays, which pass through the object to be measured on the object stage and are imaged on the imaging plate. The rear end of the imaging plate is connected with a computer data acquisition system, and image data are directly read into a computer. The computer now obtains a two-dimensional image of the sample on the turntable at an angle. And rotating the object stage to the next angle to obtain a two-dimensional image under the second angle. And sequentially obtaining two-dimensional image sequences of the measured object under different angles through rotating for a circle. And carrying out image processing on the obtained projection sequence according to requirements, and then reconstructing to obtain a tomographic image sequence. The tomographic image sequence is displayed as a three-dimensional stereoscopic image using various three-dimensional image display methods.

Since Micro CT has a spatial resolution of the order of micrometers, it is determined that the focal spot of the X-ray source should necessarily also be of the order of micrometers, typically a few micrometers. While the cone angle of the source is fixed, it is best to improve the spatial separation of the system at degrees by increasing the magnification of the object. However, because the rotating console is located on the focal point of the X-ray source and the central line of the detector, if the magnification of the object is continuously increased, that is, the object is continuously close to the X-ray source, and the field of view of the rotating console is limited, the object will inevitably exceed the field of view, and the area of the object which can be exposed to light is smaller and smaller. When such a projection map is generated, the projection data cannot be reconstructed into complete tomographic data according to the principle of the FDK reconstruction algorithm.

Three-dimensional reconstruction of objects is a common scientific problem and core technology in the fields of Computer Aided Geometric Design (CAGD), Computer Graphics (CG), computer animation, computer vision, medical image processing, scientific computing and virtual reality, digital media authoring, and the like. There are two main types of methods for generating three-dimensional representations of objects in computers. One is to use geometric modeling software to generate a three-dimensional geometric model of an object under artificial control through human-computer interaction, and the other is to acquire the geometric shape of a real object through a certain means. The former implementation technology is mature, and a plurality of software supports are available, such as 3DMAX, Maya, AutoCAD, UG and the like, which generally use curve surfaces with mathematical expressions to represent geometric shapes. The latter is generally called three-dimensional reconstruction process, which refers to mathematical process and computer technology for recovering three-dimensional information (shape, etc.) of an object by using two-dimensional projection, and includes steps of data acquisition, preprocessing, point cloud stitching, feature analysis, etc. And (5) carrying out the following steps.

The currently adopted MicroCT can not be accurately positioned in the three-dimensional reconstruction in the process of 3D reconstruction of tumor metastasis bone destruction, not only influences the specific condition of tumor metastasis bone destruction, but also deeply influences the subsequent test.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides an experimental method for scanning tumor metastasis bone destruction 3D reconstruction by using MicroCT, and solves the problems that not only the specific condition of tumor metastasis bone destruction is influenced, but also the serious influence is deeply caused to the subsequent test because MicroCT cannot be accurately positioned in three-dimensional reconstruction in the process of destroying the tumor metastasis bone and reconstructing the 3D.

In order to realize the advantages that the reconstruction of the tumor metastasis bone destruction is more accurately positioned in the three-dimensional reconstruction, the specific situation of the tumor metastasis bone destruction can be clearly known, and the like, the invention provides the following technical scheme: an experimental method for 3D reconstruction of metastatic bone destruction of tumor by using MicroCT scanning comprises the following steps,

s1, placing the white mouse with damaged bones into a scanning tube after anesthesia treatment;

s2, carrying out the whole scanning process by adopting the MicroCT, realizing the all-position intermittent movement of the scanning tube in the whole description process, reconstructing the area of each angle in a scanning frame, calculating the information of the corresponding projection image in each scanning frame in detail and reconstructing in a segmented manner, and efficiently realizing the projection of each angle;

s3, adjusting the scanning tube to the uppermost segment of the segmented reconstruction area of the collected bone destruction part, scanning each segmented part in sequence, and performing reconstruction processing on each segment to finally obtain a 3D reconstructed comprehensive tomogram of the bone destruction;

s4, performing preliminary analysis on the two-dimensional image data obtained by scanning by using a VMS system, Xming and PuTTY _ V0.63 software of the uCT-100, and setting different thresholds for the parts of the white mouse with bone destruction respectively, thereby realizing 3D reconstruction of the bone destruction through a VMS system program.

Preferably, the scanning parameters of the MicroCT are as follows: kilovolt peak 90kvp, current 210uA, resolution 48.9um, exposure time 350 ms.

Preferably, the method further comprises the step of initializing a MicroCT imaging system device for judging the identification of the initial position and the final position of the white rat bone fracture.

Preferably, the scanning tube is positioned at the origin in the vertical direction before scanning the mouse in the scanning tube, and the voltage and current suitable for the object are adjusted, the resolution of the acquired image is set, and the frame rate of the image acquisition is set.

Preferably, CGTS-RB NPs are injected prior to scanning of mice.

Preferably, the amplitude of the movement of the scanning tube to achieve the full-position discontinuity in the method step S2 is between 0 and 5 degrees, and the region to be tumor-metastasized and bone-destroyed is identified on the projection of the whole mouse.

Preferably, method step S3 specifies a reconstruction region scan frame size of 600 pixels, and if the selected region is larger than 600 pixels, the selected reconstruction region is set to an integer multiple of 600.

Preferably, a CCD detector is arranged outside the MicroCT scanning, and the CCD detector and the X-ray source have the same center height.

Preferably, the maximum distance of the transverse movement of the scanning tube is outside the field of view of the CCD detector.

Compared with the prior art, the invention provides an experimental method for 3D reconstruction by using MicroCT to scan tumor metastasis bone destruction, and the experimental method has the following beneficial effects:

according to the experimental method for scanning the tumor metastasis bone destruction 3D reconstruction by using the MicroCT, the scanning tube is used for realizing all-position discontinuous movement in the whole scanning process, the regions of all angles are reconstructed in the scanning frames, the information of the corresponding projection images in all the scanning frames is calculated in detail and reconstructed in a segmented mode, the projection of all the angles is realized efficiently, the more accurate positioning of the reconstruction of the tumor metastasis bone destruction to the three-dimensional reconstruction is ensured, the specific situation of the tumor metastasis bone destruction can be known in a detail mode, and the follow-up deep experimental study is facilitated.

Drawings

FIG. 1 is a block flow diagram of the present invention;

FIG. 2 is a structural diagram of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the contents in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-2, the present invention discloses an experimental method for bone destruction 3D reconstruction using micro ct scanning tumor metastasis, the method comprising the following steps,

s1, placing the white mouse with damaged bones into a scanning tube after anesthesia treatment;

s2, carrying out the whole scanning process by adopting the MicroCT, realizing the all-position intermittent movement of the scanning tube in the whole description process, reconstructing the area of each angle in a scanning frame, calculating the information of the corresponding projection image in each scanning frame in detail and reconstructing in a segmented manner, and efficiently realizing the projection of each angle;

s3, adjusting the scanning tube to the uppermost segment of the segmented reconstruction area of the collected bone destruction part, scanning each segmented part in sequence, and performing reconstruction processing on each segment to finally obtain a 3D reconstructed comprehensive tomogram of the bone destruction;

s4, performing preliminary analysis on the two-dimensional image data obtained by scanning by using a VMS system, Xming and PuTTY _ V0.63 software of the uCT-100, and setting different thresholds for the parts of the white mouse with bone destruction respectively, thereby realizing 3D reconstruction of the bone destruction through a VMS system program.

The Micro-CT imaging principle is that the layer of each part of the small animal is scanned and projected by adopting a Micro-focus X-ray bulb tube, the X-ray penetrating through the layer is received by a detector, converted into visible light, converted into an electric signal by a photoelectric converter, converted into a digital signal by an analog/digital converter and input into a computer for imaging.

2 basic structures of MicroCT:

the sample is static, the x-ray tube and the detector move, the structure and the clinical spiral CT-cause, the tube rotates around the sample. The scanning speed is fast, the ray dose is small, the spatial resolution is low, and the method is mainly used for scanning living animals. The sample moves, the X-ray bulb tube is fixed with the detector, and the sample spins between the bulb tube and the detector and can move up and down and back and forth. The scanning speed is slower, the ray dosage is large, the spatial resolution is high, and the device is mainly used for scanning in vitro specimens.

MicroCT class 2 application object

In vivo (vivo) the subject is usually a small living animal such as a mouse, rat or rabbit, which is anesthetized or fixed and then scanned. Longitudinal research on physiological metabolism function can be realized, and the number of animals required by animal experiments is obviously reduced. Similar to medical clinical CT, live small animal MicroCT is also capable of respiratory gating and enhanced scanning (with contrast agents). In vitro (in vitro) the subject of study is usually an ex vivo specimen (e.g. bone, tooth) or a sample of various materials, which is analyzed for internal structure and mechanical properties. Live animals may also be perfused with a solidifying contrast agent for fine imaging of the cardiovascular, urinary or digestive system.

After the script program to be measured is completed, the system generates a COOO1806_ VOI _ bic.gobj; 3, opening and checking a two-dimensional image file, wherein 2 closed irregular graph areas are arranged around the implant, the graph area of the inner layer represents an area D1 of the metal implant, the interlayer area between the graph of the outer layer and the graph of the inner layer represents an area D2 of cancellous bone combined with the implant, and through observation, if D1 is infinitely close to the implant and D2 is infinitely close to the surrounding cancellous bone, the parameters such as the threshold value and the like which are arranged in the front are accurate and effective, and then the next-step analysis can be carried out; otherwise, the method needs to return to the previous step again, reset the relevant parameters such as the threshold value, and then proceed to the next step after D1 and D2 are correct.

Software post-processing:

the data interface is in the format of DICOM, JPEG, TIFF, BMP, IM0, RAW, etc.

The input and output two-dimensional processing of the image file comprises image browsing, selecting, processing and displaying, two-dimensional geometric transformation and measurement, continuous image playing and the like.

Three-dimensional processing, namely three-dimensional tissue segmentation, surface model reconstruction and layered display, and slice recombination.

Three-dimensional display, namely realistic display, illumination parameter adjustment, three-dimensional geometric transformation and three-dimensional measurement image segmentation, wherein a plurality of segmentation methods (Fast Marching, Level set.).

The scanning parameters of the MicroCT are as follows: kilovolt peak 90kvp, current 210uA, resolution 48.9um, exposure time 350 ms. The method also comprises a step of carrying out initialization work by using a MicroCT imaging system device for judging the identification of the initial position and the final position of the white rat bone fracture.

Before a mouse in the scanning tube is scanned, the scanning tube is positioned at the origin in the vertical direction, the voltage and the current suitable for an object are adjusted, the resolution of an acquired image is set, and the frame rate of the image acquisition is set.

Injecting CGTS-RB NPs prior to scanning mice; the capability of the CT contrast agent can be greatly improved by using CGTS-RB NPs, and the injection dose is (2mg/mL,25 mu L) for carrying out intratumoral injection observation on mice. The scan results show that the tumor after injection is clearly visible compared to no signal before injection (HU value 127. method step S2 where the amplitude of the movement of the scanning tube to achieve full position discontinuity is between 0 and 5 degrees, identifying the area of bone destruction to metastasis in the entire mouse projection image. method step S3 specifies that the size of the reconstruction region scan box is 600 pixels, and if the selected region is greater than 600 kerfs, the selected reconstruction region is set to an integer multiple of 600.

A CCD detector is arranged outside the MicroCT scanning, and the CCD detector and the X-ray source have the same center height. The maximum distance of the transverse movement of the scanning tube is out of the visual field range of the CCD detector; the CCD detector is a high-sensitivity semiconductor device and is used for analyzing weak Raman signals.

The working process and principle of the invention are as follows: firstly, CGTS-RB NPs are scanned and injected to a mouse, the mouse with damaged bones used in an experiment is placed into a scanning tube after anesthesia treatment, MicroCT imaging system equipment for judging the initial position and the final position of the broken bones of the mouse is used for initialization work, MicroCT is adopted for scanning the whole process, the scanning tube realizes full-position discontinuous movement in the whole description process, the regions of all angles are reconstructed in a scanning frame, and the scanning parameters of MicroCT are as follows: kilovolt peak value 90kvp, current 210uA, resolution 48.9um and exposure time 350ms, calculating information of corresponding projection images in each scanning frame in a segmented reconstruction mode in detail, efficiently realizing projection of each angle, adjusting a scanning tube to the uppermost section of a segmented reconstruction area of an acquired bone destruction part, scanning each segmented part in sequence, reconstructing each segment, realizing that the amplitude of all-position discontinuous movement is between 0 and 5 degrees, identifying a bone destruction area to be subjected to tumor metastasis on a projection image of the whole white mouse, enabling the scanning tube to be at the origin in the vertical direction before scanning the white mouse in the scanning tube, adjusting voltage and current suitable for an object, setting acquired image resolution, setting an image acquisition frame rate, and finally obtaining a reconstructed comprehensive tomogram of a bone destruction 3D, adjusting the scanning tube to the uppermost section of the segmented reconstruction area of the acquired bone destruction part, scanning each subsection part in sequence, carrying out reconstruction processing on each subsection to finally obtain a reconstructed comprehensive tomogram of the bone destruction 3D, wherein the size of a scanning frame of a reconstruction region is 600 pixels, if the selected region is more than 600 image cables, setting the selected reconstruction area as an integral multiple of 600, performing preliminary analysis on the scanned two-dimensional image data by using a VMS system, Xming and PuTTY _ V0.63 software of the uCT-100, respectively setting different threshold values for the parts of the white mouse with bone destruction, thus, the above-described 3D reconstruction of bone destruction by the VMS system program, is only a preferred embodiment of the present invention, the scope of the present invention is not limited thereto, and any person skilled in the art can easily understand the technical scope of the present invention, the technical solution and the inventive concept thereof according to the present invention should be equally replaced or changed within the protection scope of the present invention.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.