Implementation And Verification Of 3d Ultrasound Reconstruction Module For SLICER

With the development of computer and medical technique in our country, research on 3D ultrasound is being paid more and more attention. 3D ultrasound not only has the advantages of real-time image processing, harmless to human, portable, low cost and safe which traditional ultrasound has, but also have its own advantages of clinical significance, computer-aided diagnosis, can be accurate measurement of the structure. 3D ultrasonic equipment is used by more and more hospital, mainly for the diagnosis and surgical navigation. Although the dedicated 3D ultrasonic probe have already existed, due to a variety of reasons, the main approach to obtain 3d ultrasound data is still using 2D ultrasound images to reconstruct into a 3D ultrasound image. By reconstructing traditional 2D ultrasound images into 3D ultrasound ones, human organs and tissues can be showed on the screen more directly and clearly. By HMI, doctors can operate 3d ultrasound image, such as translation, rotation , scaling and so on, it can make them fully understand 3d spatial relationships among Human tissue, thus more easily make clinical diagnoses.This article focuses on the development of 3D ultrasound reconstruction technology home and abroad, its algorithm and implementation, its principles and implementation of calibration system, 3D ultrasound module research of integration and application for Slicer.With respect to technology development home and abroad: Theoretical research of 3D ultrasound reconstruction is mature, we can design a software which applies to clinical medicine. The primary process of 3D ultrasound reconstruction includes acquirement of image and coordinates, device (ultrasound machine and tracking machine) calibration(time calibration and spacing calibration), 3D ultrasound reconstruction(core: reconstruction algorithm), experimental verification(accuracy and correctness) and rendering(three sections show, surface rendering, volume rendering). Research of 3D ultrasound reconstruction at home is still in the initial stage, mainly research application.With respect to algorithm and the implementation of 3D ultrasound reconstruction: Tracker will be fixed on the probe, and then we can acquire ultrasound image and position in the same time. Most of reconstruction algorithm can't accomplish the work before we collect whole data, so it can't reconstruct into a 3D ultrasound image in real-time. In this paper, we will describe and implement a real-time ultrasound reconstruction technology which satisfies the requirements on both speed and quality. After reconstruction, 3D ultrasound data will be put in a predefined grid.With respect to principles and implementation of calibration system in 3D ultrasound reconstruction: Calibration includes time calibration and spacing calibration.1. Spacing calibration: Freehand 3D ultrasound reconstruction technology tells us to fix tracker on the probe, so doctor can use this type of probe to reconstruct ultrasound image according to free path. This technology need calibration before reconstruction, the purpose of calibration is finding a group of transformation matrix, these matrix can convert a pixel in 2D image into a voxel in grid to make up inaccuracy of tracker.2. Time calibration: Transmission data of ultrasound and tracker machine is discrete and has different latency, this should use time calibration to find relevant position which matches its 2D ultrasound image.With respect to integration and application of 3D ultrasound reconstruction for Slicer: 3D Slicer is a comprehensive medical image processing platform, this chapter will discuss how to integrate 3D ultrasound reconstruction module into Slicer and application of this module in Slicer.