1. Duke Breast Models Prepared for Allergan & Ansys
Paul Segars
Greg Sturgeon

2. Types of Data Breast MRI (prone) Patient CT (supine) Breast CT (prone)
Resolution: 0.85 mm XY; 1.6 mm Z
Breast CT (prone)
Resolution: 0.97 mm XY; 3.27 mm Z
Resolution: to 0.25 mm

3. Two Sources of Breast Models
Full Body XCAT Models
Isolated High Resolution Breast Models
Based on patient CT data
with ‘morphed’ structures
Segmented breast CT data

4. Full Body XCAT Models Based on patient CT data
~3000 structures modeled as individual NURBS surfaces.
Some objects built from patient specific segmentations
Some ‘morphed’ from detailed reference phantoms

5. Extrapolating the FOV
Part of the torso or breast may be outside of the reconstruction in some CT scans.
NURBS surfaces created for the overall body habitus and breasts.
Geometry is extrapolated from imaging and patient BMI.
Full-body XCAT models do not currently have patient specific fibroglandular tissue or ducts modeled.
Possible to segment inner tissue from CT if not truncated

6. Variability of Full Body XCAT Models

7. High Resolution Breast Models
Segmented Breast CT
.155 mm voxel resolution
Segmented into 6 classes
(skin + 4 fibroglandular levels + adipose)
Imaged in pendant geometry
Limited pectoral muscle / no chestwall

8. Size / Density Variability of High Resolution (isolated) Breast Models

9. Addition of Breast (based upon Breast CT) to XCAT model+

10. FE compression using template hex mesh
Modeled gravity and compression to allow for simulated mammography and breast tomosynthesis imaging.
Chest wall modeled simplistically
Patient specific chest wall information wasn’t available for these cases.
Use of template mesh allowed for easy mapping between breast geometries.
Allow for breasts to be mapped to consistent shell.

11. Subpopulation of breast models – mapped to consistent geometry
Subpopulation of larger less dense breasts.
Mapped to a consistent compressed breast ‘shell’.
Allows of modeling of breast texture independent of geometry.