Transcript segars_ISMRM_presentation - Carl E Ravin Advanced Imaging

4D XCAT Phantom for
Multimodality Imaging
Research
CARL E RAVIN
ADVANCED
I M A G I N G
LABORATORIES
W. Paul Segars, PhD
Carl E. Ravin Advanced Imaging Labs
Duke University
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
Computational Models
• 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
• 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
XCAT Phantoms
• Based on Human Imaging Data
• Structures realistically defined using NURBS
surfaces, widely used in computer graphics
Male
Female
5
4D XCAT Phantom Anatomy
Detailed Brain Model based on MRI
4D XCAT Phantom Anatomy
Detailed Breast Models of Different Densities Based
on Breast CT
Imaging Simulations using the
Computerized XCAT Phantoms
8
Breast Imaging Simulations Using the
4D XCAT Phantom
MRI
Mammography
CT
Tomosynthesis
Ultrasound
Positron
Emission
Mammography
Simulation of 4D Data
Cardiac Model
Respiratory Model
End-expiration
End-diastole
End-systole
End-inspiration
10
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
58 Adult Phantoms
12
42 Pediatric Phantoms
13
Anatomical Variations
Males
BMI: 21.9
BMI: 22.7
BMI: 28.5
BMI: 36.1
Anatomical Variations
Females
BMI: 18.2
BMI: 22.3
BMI: 28.6
BMI: 35.5
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
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