Research On Registration Of Deformation Image And2D-3D Image In Radiotherapy

The breath of patient, the peristalsis of viscera and the motion of position can cause themigration of target location in radiation therapy. Image guided radiation therapy technologycan track the position of patient and target in real time by use of the biological imagingtechniques，can reduce the error of the position of patient beam and the error of organsdisplacement. Image guided radiation therapy technology can determine the location of targetby means of registration of the collect image of patient and avoid dose irradiate the normaltissue effectively. Deformation image registration and2D-3D registration are the keytechnology of image guided radiation therapy, can determine the location of target and theposition of patient.Deformable registration can determine degeneration and displacement changes ofanatomical tissue in radiotherapy and guide sketch the target and formulate radiotherapy planin use of judging the degree of influence to the dose due to the movement of organs.2D-3Dregistration is the registration of volume data before radiation therapy and X image inradiotherapy, can guide the placement of the treatment bed and the patients and guarantees thereal-time and the accuracy of radiation treatment. The paper discusses the registration of thedeformation image and2D-3D image and research the deformation image registration basedon affine transformation and b-spline free deformation, the paper improves the performanceand the accuracy of the algorithm; The paper realizes2D-3D medical image registration basedon gradient correlation and pattern intensity similarity measurement, discusses calculationprinciple and process of the pattern intensity similarity measurement and simplifies theprocess of calculation. The paper makes the following research:The paper analyses the background, significance and research status of deformationregistration and2D-3D image registration in radiation therapy. At the same time, the paperimproves the registration algorithm to solve the low precision and long operation time indeformation registration and2D-3D image registration.The paper researches the image registration based on b-spline free deformation. Thepaper uses affine transformation as a global coarse registration and b-spline free deformationas a local accurate registration. In order to improve the accuracy of registration and reduce thecomplexity of calculation, the paper introduces the multi-resolution strategy and finishes theregistration of the single mode images and multimodal images. The experiment verifiesalgorithm has the high accuracy.On the basis of in-depth research of the principle of2D-3D medical image registration,the paper combines the pattern intensity and the gradient and simplifies the calculation of thepattern intensity similarity measure against the computationally complex and time consuming process of registration. At the same time, the paper uses of graphics processing unit (GPU)multithreaded parallel computing to finish the DRR formation and the similarity measure inthe GPU and introduces gradient descent and multi-resolution to optimize strategiesregistration process.