4D XCAT Phantom for Multimodality Imaging Research

1. 4D XCAT Phantom for Multimodality Imaging Research W. Paul Segars, PhD Carl E. Ravin Advanced Imaging Labs Duke University

2. Computational Models and Medical Imaging Simulation • Computational models or phantoms • Provide a model of the subject’s anatomy and physiology • Models of the physics of the imaging process • Simulate imaging procedures on the phantom patient Computer model of X-ray CT scanner X-ray CT Simulation Simulated CT Images of the Phantom

3. Exact anatomy and physiology of the computer phantom are known providing a gold standard to evaluate and improve devices and techniques Computer phantoms have been used extensively to: Optimize imaging systems design and protocols Aid in the development and evaluation of new image reconstruction and correction algorithms Computational Models

4. Realistic models of anatomy and physiology are vital Without such, simulated results may not be indicative of what would occur in live experiments The development of realistic computational models is one of the most active areas of research in imaging and radiation dosimetry Computational Models

5. XCAT Phantoms • Based on Human Imaging Data • Structures realistically defined using NURBS surfaces, widely used in computer graphics Male Female

6. 4D XCAT Phantom Anatomy Detailed Brain Model based on MRI

7. 4D XCAT Phantom Anatomy Detailed Breast Models of Different Densities Based on Breast CT

8. Imaging Simulations using the Computerized XCAT Phantoms 8

9. Breast Imaging Simulations Using the 4D XCAT Phantom MRI Mammography CT Tomosynthesis Ultrasound Positron Emission Mammography

10. Simulation of 4D Data Cardiac Model Respiratory Model End-expiration End-inspiration End-systole End-diastole 10

11. Population of 4D XCAT Phantoms Create a population of hundreds of detailed phantoms to represent the public at large from infancy to adulthood Modeling patient variability is essential to mimic clinical trials Include cardiac and respiratory motions for 4D simulations First library of 4D phantoms

12. 58 Adult Phantoms 12

13. 42 Pediatric Phantoms 13

14. Anatomical Variations Males BMI: 21.9 BMI: 22.7 BMI: 28.5 BMI: 36.1

15. Anatomical Variations Females BMI: 18.2 BMI: 22.3 BMI: 28.6 BMI: 35.5

16. Conclusion • The population of XCAT phantoms provide a valuable resource for investigating different imaging devices and the effects of anatomy and motion in imaging • Combined with accurate models for the imaging process, the phantoms can provide a wealth of realistic, predictive imaging data to serve as a known truth from which to evaluate and improve imaging devices and techniques

17. Conclusion • The phantoms have enormous potential to research new image acquisition strategies, image processing and reconstruction methods • In future work, we plan to further expand this library, ultimately to a population of hundreds of phantoms ranging in age from newborn to adult • Such a large compilation of phantoms will provide a great research tool for the imaging community