Presentation is loading. Please wait.

Presentation is loading. Please wait.

1 Improved Techniques for Fast Sliding Thin-Slab Volume Visualization Janice Z Turlington*, William E. Higgins* ** Electrical Engineering, ** The BioEngineering.

Similar presentations


Presentation on theme: "1 Improved Techniques for Fast Sliding Thin-Slab Volume Visualization Janice Z Turlington*, William E. Higgins* ** Electrical Engineering, ** The BioEngineering."— Presentation transcript:

1 1 Improved Techniques for Fast Sliding Thin-Slab Volume Visualization Janice Z Turlington*, William E. Higgins* ** Electrical Engineering, ** The BioEngineering Program, and * Computer Science and Engineering The Pennsylvania State University, University Park, PA 16802 SPIE Medical Imaging 2000, San Diego CA, 13 February

2 2 Motivation Locate small structures in 3D CT volume Objectives Show “true” information Confident results for professional use Fast techniques for real-time use

3 3 Existing Visualization Techniques projection imaging 1 curved-section reformatting 3 volume/surface rendering 4 multi-planar reconstruction 2 virtual endoscopic rendering 5

4 4 Existing Limitations dependence on a priori knowledge voxel intensity decisions partial-volume artifacts voxel boundaries 1 {Hohne87,Napel92} 2 {Robb1988,Remy96,McGuinness97} 3 {Robb1988,Hara96,Ramaswamy99} 4 {Ney90,Drebin88,Tiede90} 5 {Vining94,Ramaswamy99}

5 5 Sliding Thin-Slab Visualization improve understanding of lung changes more precise characterization of distribution changes {Remy-Jardin et al. 96} {Napel 92} (STS-MIP)

6 6 Our New STS Techniques f ast general-purpose algorithms dynamic sequence visualization accurate 3D impression slab change volume evolution (DWmax) Depth-Weighted Maximum (DWmax) Extreme Gradient (EG)

7 7 volume window column point slab Sliding Thin-Slab Movement

8 8 Fast STS Algorithms temporal coherence 1 adjacent views change little only 2 slices differ slab i window calculations apply to slab i+1 1 {Ramaswamy1999}

9 9 Depth-Weighted Maximum (DWmax) w i = (depth of view – distance i from base)

10 10 Depth-Weighting: 1 D process

11 11. sub-volume DWmax Algorithms volume column

12 12 STS-MIPDWmax {Turlington 2000}{Napel 1992} CT image slice

13 13 DWmax: Transverse Sequence Views s=28 s=43s=49

14 14 DWmax: coronal detail coronal sequence views single slice projection image

15 15 DWmax: sagittal detail base slice

16 16

17 17 Extreme Gradient (EG) Mapping of max tissue-density changes in slab s(x,y) = max x,y { } – max x,y { }

18 18 sub-volume volume column EG Algorithms

19 19 small change large change moderate change Extreme Gradient EG not windowed image extremes structure size slab size Function of:

20 20 Endoluminal Border Detection merging DWmax and EG

21 21 Computation Gains of New Techniques inversely proportionally to slab-size ( d s )

22 22 Current Reconstruction Techniques cross-sectional imaging is CT gold standard axial images alone enable remarkably accurate assessment true paradigm shift requires comparison to traditional methods {Naidich et al. 97}

23 23 lymph node detection S=39 currently under development

24 24 lymph node? EG: soft tissue EG: high density DWmax

25 25 Conclusion: New Techniques fast, real-time small structures visible depth perception true information

26 26 My thanks to: Dr. William E. Higgins The Whitaker Foundation Dr. K. Kirk Shung Dr. Cheng Dong My Father “For nothing is hidden, except to be revealed; nor has been secret, but that it should come to light.” Mark 4:22

27 27 2:40 pm Today … California Room A. J. Sherbondy Virtual Bronchoscopic Approach Combining 3D CT and Endoscopic Video Physiology and Functions from Multidimensional Images Conference 3978 5:30 to 7:30 pm Today…California Room G. McLennan The Place of Virtual Bronchoscopy in Clinical Practice: Barriers and Solutions Physiology and Functions from Multidimensional Images Conference 3978

28 28 DWmax error NOT visible Occurs in less than 2%of points must occur simultaneously: 1.closer to base than voxel of previous slab’s max 2.depth-weighted voxel must differ: < 5.5% of 16-bit previous-slab point (=0.7% 8-bit) if error occurs: errror < 5 HU (16-bit) or 0 HU (8-bit)


Download ppt "1 Improved Techniques for Fast Sliding Thin-Slab Volume Visualization Janice Z Turlington*, William E. Higgins* ** Electrical Engineering, ** The BioEngineering."

Similar presentations


Ads by Google