Title: Model-Based%20Registration%20of%20X-ray%20Mammograms%20and%20MR%20Images%20of%20the%20Female%20Breast
1Model-Based Registration of X-ray Mammograms and
MR Images of the Female Breast
- N.V. Ruiter, T.O. Müller, R. Stotzka, H.
Gemmeke,Forschungszentrum Karlsruhe, Germany
2Motivation
Support multimodal breast cancer diagnosis
MR image
- Locate lesion in complementary modality
X-ray mammogram
? Registration Find geometric
correspondence
3Registration Problem
Images not directly comparable !
- X-ray mammography
- 2D projection
- Large deformation
- Only one projection per deformation
? Add information using a biomechanical
model
4Process of Registration
5Problems of Deformation Model
- Large deformation of soft tissue
- Details of deformation process unknown
- Exact patient position
- 3D shape of breast
- Thickness of deformed breast
- Compression force
- Tissues of the breast
- Only large scale structures resolved in MR image
- Material models in literature
- Inconclusive
- Not plausible for large deformation
Plate compression
6Specification of Deformation Model
- Adapt global parameters
- Projection angle by non-linear scaling
- Volume is preserved ? estimate thickness
- Finite Element Model
- Large deformations (gtgt5), (nearly)
incompressible materials - Material model
- Evaluation of models for breast tissue
- ? Neo Hookean model, homogeneous tissues
- Two step modeling of deformation
- 1st step Mammographic deformation
- 2nd step Fine tuning using mammogram
Mammographicdeformation
7Results with Clinical Datasets
- Six clinical data sets Lesion position in X-ray
mammograms and MR image known - Smallest visible lesions in MR images 5 mm
- Prediction of lesion position
- MRI ? X-ray
- Mean center distance 4.3 mm (2.3 6 mm)
- Mean area overlap 81
- X-ray ? MRI
- Mean center distance 3.9 mm (1.6 6.4 mm)
- Mean volume overlap 91
8Results with Clinical Datasets
- MRI ?X-ray craniocaudal example
X-ray mammogram
Direct MR projection
9Conclusions
- Registration overcomes 3D deformation
- Successful first evaluation
- Localization with approx. 5 mm deviation
(smallest visible lesion) - Clinical evaluation
- Possible applications
- Support multimodal breast cancer diagnosis
(also alternative 3D modalities) - Simulation of breast deformation
10Thank you !
11Results with Clinical Datasets
123D Localization in MR Image
- Two simulations necessary
Oblique X-ray mammogram
Cranio-caudal X-ray mammogram
13Registrierungskomponenten I
- ? Integration Deformationsmodell in
Registrierung - MRT ? patientenspezifische Geometrie FE Modell
- I. Simulation Mammographische Deformation
- Projektionswinkel und Länge? 2D Registrierung
- Dickenänderung? aus Volumenerhaltung
?
MRT
FE Modell
FE Modell mit Platten
14Registrierungskomponenten II
- II.Simulation Feinabstimmung Mammogramm
- Ergebnis der I.Simulation Näherung 3D
deformierte Brust - Vergleich Konturen Schätzung 3D Brust
- II.Simulation mit korrigierten Randbedingungen
? Individuell deformierte 3D Brust
15Objective and Problems
Register X-ray mammograms and MR volumes? Locate
lesion in complementary modality
- MR Image
- 3D volume, undeformed breast
- X-ray mammography
- 2 projections, 2D,hugely deformed breast
- Only 1 projection per deformation? Images not
directly comparable !
- Additional information by model of deformation
16Motivation
Support multimodal breast cancer diagnosis
MR volume
- Fuse X-ray mammograms and MR volume
- Predict lesion position in complementary modality
X-ray mammogram
- Registration Find geometric correspondence