1. System Overview
3D medical imaging PACS system, which integrates image storage server, imaging diagnosis workstation and RIS reporting system, mainly includes image processing module, image data management module, RIS reporting module, CD archiving module, DICOM communication module, film printout and other modules It has complete image database management functions and powerful image post-processing functions, which improves the accuracy of clinical diagnosis.
2. Three-dimensional image reconstruction
Supports 3D image processing functions; 3D reconstruction, maximum/minimum density projection, 3D volume reconstruction, 3D surface reconstruction, virtual endoscopy, surface reconstruction, and cardiac image coronary calcium score.
1. Multi-planar reconstruction (MPR)
Definition: MPR is interactive navigation in any direction of a three-dimensional volume. MPR can simultaneously display the axial, sagittal, coronal and any oblique slices, and can arbitrarily change the reconstructed position and layer thickness to facilitate observation of the subtleties of different tissues. structure. MPR can better display the complex anatomical relationships within tissues and organs, which is beneficial to the accurate location of lesions.
Application: Display the morphological changes of organs in various systems of the body, and various systems of the body (location of lesions, adjacent relationship, extent of invasion, relationship with large blood vessels, etc.).
Advantages: Fast reconstruction; less data loss; mixed with other reconstruction methods.
Disadvantages: single plane; low z-axis spatial resolution; volume scan data required; step-like artifacts.
2. Surface reconstruction (CPR)
Definition: It is a special method of MPR, suitable for displaying some curved structural organs of the human body, such as jaws, tortuous blood vessels, bronchi, ureters, pancreatic bile ducts, etc.
3. Volume reconstruction (VR)
Mask imaging was performed on all volumetric data.
VR is currently one of the most commonly used technologies in multi-slice spiral CT three-dimensional image post-processing.
Advantages: display three-dimensional structure; beautiful; widely used.
Application: All kinds of 3D reconstruction.
4. Virtual endoscope (VE)
Definition: Also called intracavity reconstruction technology, it refers to adjusting the CT threshold and tissue transparency. It is not necessary to observe the tissue transparency to 100% and eliminate its image; it is necessary to observe the tissue transparency to 0, retain its image, and then adjust the artificial false color. Obtain similar fiberscope images and rely on navigation methods to display intraluminal structures.
Advantages: Non-invasive, showing the inner surface structures of hollow organs, airways, and blood vessels.
Application: Simulated colonoscopy, gastroscopy, bronchoscopy.
3. Basic principles of 3D reconstruction technology
In the PACS system, the three-dimensional reconstruction technology is based on a series of two-dimensional slice images. The images are processed through mathematical and computer algorithms to restore the three-dimensional structure of the object. The application of this technology in the medical field has achieved remarkable results, such as CT, MRI (nuclear magnetic resonance), etc.
4. Application process
A complete 3D reconstruction process includes data acquisition from the PACS system, preprocessing, registration, reconstruction and visualization.
Prerequisite: Obtain data from PACS system
First, export the original 2D image data from the PACS system. These data may be files in DICOM format and need to be read and parsed using relevant libraries.
1. Image preprocessing
First, export the original 2D image data from the PACS system. These data may contain noise, artifacts and other factors that affect the 3D reconstruction effect, so preprocessing is required.
2. Image registration
Image registration is to align images acquired at different times and angles for fusion in subsequent steps.
3. 3D reconstruction
Next, the preprocessed 2D images are used for 3D reconstruction, where the 2D slices are stacked into a 3D structure.
4. 3D model visualization
Finally, we visually display the reconstructed 3D model and realize the rendering and interaction of the 3D model.
5.Image processing
Image display: Display images of patients in different positions and different equipment on the same screen for diagnostic comparison and inspection; the display matrix can be adjusted arbitrarily; relevant information of the displayed image can be customized, such as name, age, equipment model and other parameters.
Image processing functions: Provide window width/window level adjustment, negative image, image roaming, zoom, rotation, mirroring, dynamic video capture, pseudo color, playback and other functions.
Measurement analysis: length, angle, area measurement, regional density analysis; image annotation: straight lines, arrows, rectangles, ellipses, polygons, hand-drawn lines, text and other format annotations, etc.
Image enhancement: image smoothing, edge enhancement, contrast adjustment, noise reduction filtering, histogram equalization, sculpting effect, sharpening, etc.
Image playback: supports digital movie playback, the playback speed can be adjusted arbitrarily, single frame, multiple frames, and dynamic playback of archived images.
Parameter settings: Support user-defined window width and window level value, display text size, magnifying glass magnification ratio and other parameter adjustments.
Various medical image files can be output to film or medical printing paper through laser cameras.
Images from different imaging devices at different stages of the patient's life can be compared for diagnosis.
Supports multi-screen and portrait display modes; supports diagnostic-grade high-resolution, high-brightness professional displays from professional manufacturers. Shortcuts or shortcut keys can be used to perform corresponding functions.