Methodology Of Establishing 3D Printed Left Heart Model By Using Ultrasound-CT Multimodal Image Fusion Technology

Multimodal medical imaging refers to image data obtained from various non-invasive imaging techniques,such as echocardiography,radionuclide technology,multi-row computed tomography(CT),and cardiac nuclear magnetic resonance(MRI).Combining anatomical,morphological,and organ function data helps to accurately diagnose disease and improve cardiovascular disease intervention and clinical outcomes.Over the past decade,ever-evolving software and hardware have allowed image data from a variety of imaging modalities to be fused together,called cardiac fusion imaging.Three-dimensional(3D)printing has been gradually applied to the heart field in recent years.Image data sources usually come from high-resolution cardiac CT,which can well display the overall structure of the heart,but CT often requires venography,patients are exposed to ionizing radiation,and CT For the heart valve structure is not as good as ultrasound imaging,and with the spatial resolution and accuracy of the three-dimensional reconstruction of the heart valve structure,so in view of the advantages and disadvantages of CT and ultrasound medical images of different modes,the study It is planned to complement each other’s advantages,and combine the left heart valve with the CT left heart image to explore the methodology and accuracy of multi-modal image fusion cardiac image model through animal experiments and clinical experiments to improve the accuracy of the cardiac 3D printing model.This study is divided into two parts:Part Ⅰ: Animal Experimental Study of Applying Ultrasound-CT Image Fusion Data to 3D Print Cardiac MethodologyPart Ⅱ: Multimodal Medical Image Fusion Technology 3D Printing Left Heart Model Methodology and Precision StudyPart Ⅰ: Animal Experimental Study of Applying Ultrasound-CT Image Fusion Data to 3D Print Cardiac MethodologyObjective: This study used multimodal cardiac image fusion technology for animal experiments,and obtained ultrasound-CT cardiac image fusion methods and test indicators to evaluate the reliability of the indicators.Methods:Sixteen Beagle dogs were used to obtain images of cardiac CT and ultrasound heart valves.The image data was post-processed using Mimics 19.0 software and 3-Matic 11.0 software.The alignment points and the annulus planes were aligned to fuse the ultrasound heart valves.A digital model of the fusion left heart is obtained on the CT heart chamber.Measurement of anterior and posterior mitral anterior to apical maximal diameter,mitral posterior medial apical maximum diameter,valvular closure to apical maximum diameter,and mitral annulus plane and aorta on digital models and cardiac specimens The angle of the annulus plane.Results:The ultrasound-CT cardiac image fusion was successfully completed.The anterior and posterior mitral valve combined with the maximum diameter of the apex,the posterior medial mitral valve to the maximum diameter of the apex,the closure of the valvular valve to the maximum diameter of the apex and the mitral annulus plane There was no statistical difference in the measurement of the angle of the aortic annulus.When the angle difference of the annulus was less than 5° and the difference between the annulus plane and the apex was less than 5%,the image fusion registration could be considered accurate.Conclusion:It is feasible and accurate to perform cardiac CT-ultrasound image fusion by the internal feature method of an anatomic landmark with an annulus.The angle between the mitral annulus and the aortic annulus and the distance between the annulus plane and the apex can be As a detection indicator of registration accuracy.Part Ⅱ: Multimodal Medical Image Fusion Technology 3D Printing Left Heart Model Methodology and Precision StudyObjective:This study intends to use ultrasound valve images and CT cardiac image mosaic to provide richer anatomical information and new image processing methods for 3D printed hearts.Methods:A retrospective analysis of 41 patients with atrial fibrillation by transesophageal three-dimensional echocardiography(3D-TEE)and cardiac CTA medical digital imaging and communication(DICOM)images,using Mimics software to post-processing data.The single-modality group uses only cardiac CTA as the data source,and the multimodal group uses CT and ultrasound as the data source.The 3D reconstruction valve structure was scored,and the parameters such as the circumference and area of the annulus were measured.The images of the single-modal group and the multi-modal group were overlapped,and the angle between the two annulus planes was measured to calculate the measured values.Absolute difference,row paired t-test,Bland-Altman analysis and correlation coefficient within the group were statistically analyzed.Results:The scores of ultrasound-reconstructed valves were higher than those of CT-reconstructed valves.There were no significant differences in the parameters of the two groups(P>0.05),and the consistency was good.The mitral and aortic valve rings were examined during image registration.The mean angle and standard deviation of the plane angle are(3.15°±0.88°)and(2.87°±0.76°),respectively.Conclusion:The fusion of the ultrasound valve and the CT heart image is accurate,and the morphology of the ultrasound valve is better,which helps to improve the simulation of the 3D printed heart model.