Difference between revisions of "Projects:DBP2:Harvard:Registration Documentation"
(Created page with '= Registration = Slicer 3 contains a number of different ways to register two images. In this document we will examine the results of these modules on three different cases. The...') |
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===Affine=== | ===Affine=== | ||
+ | [[File:53-t2 aff.png|600px|thumb|left|Affine case 1: Minor loss of detail.]] | ||
*53-t2 -> 31-t1 = aff1 | *53-t2 -> 31-t1 = aff1 | ||
*aff1 -> 53-t2 = aff2 | *aff1 -> 53-t2 = aff2 | ||
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===Linear=== | ===Linear=== | ||
+ | [[File:52-t2 lin.png|600px|thumb|left|Linear case 1: Minor shift at front, loss of detail.]] | ||
*53-t2 -> 31-t1 = lin1 | *53-t2 -> 31-t1 = lin1 | ||
*lin1 -> 53-t2 = lin2 | *lin1 -> 53-t2 = lin2 | ||
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===Rigid=== | ===Rigid=== | ||
+ | [[File:53-t2 rig.png|600px|thumb|left|Rigid case 1: Significant loss of detail.]] | ||
*53-t2 -> 31-t1 = rig1 | *53-t2 -> 31-t1 = rig1 | ||
*rig1 -> 53-t2 = rig2 | *rig1 -> 53-t2 = rig2 | ||
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===Deformable B-spline=== | ===Deformable B-spline=== | ||
+ | [[File:53-t2 Bspline.png|600px|thumb|left|BSpline case 1: Serious distortions.|]] | ||
*53-t2 -> 31-t1 = Bspline1 | *53-t2 -> 31-t1 = Bspline1 | ||
*Bspline1 -> 53-t2 = Bspline2 | *Bspline1 -> 53-t2 = Bspline2 | ||
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*DTI-baseline -> 53-t2 = Bspline3 | *DTI-baseline -> 53-t2 = Bspline3 | ||
− | + | [[File:Baseline-bsp-t2-composite.png|600px|thumb|left|BSpline case 2: Matches cortex to skull.|]] | |
Fits the cortex on the baseline to the skull on the t2. Retry with a skull | Fits the cortex on the baseline to the skull on the t2. Retry with a skull | ||
stripped t2. | stripped t2. |
Revision as of 20:36, 21 April 2009
Home < Projects:DBP2:Harvard:Registration DocumentationContents
Registration
Slicer 3 contains a number of different ways to register two images. In this document we will examine the results of these modules on three different cases. The convention used will be (moving image) -> (fixed image) = (resulting moved image). The cases are:
- Registering a t2 weighted image to an arbitrary t1, then registering this transformed image back to the original t2. Ideally this will produce a identical image.
- Registering a DTI baseline image to the corresponding realigned t2 weighted image, and vice-versa. This is a realistic test of one of our (the PNL) everyday uses of registration.
- Registering a realigned t2 weighted image to another t2.
Tasks completed
Affine
- 53-t2 -> 31-t1 = aff1
- aff1 -> 53-t2 = aff2
The image shows these side by side. The are nearly the same except for the loss of fine detail.
- DTI-baseline -> 53-t2 = aff3
Image shows the 53-t2 target image and the registered image side by side. DTI distortion remains but aligned well to ventricles in center.
- 53-t2 -> DTI-baseline = aff4
The registered image does not stretch to the full extent of the DTI at the midline, though the match is quite close more laterally.
Linear
- 53-t2 -> 31-t1 = lin1
- lin1 -> 53-t2 = lin2
The image shows lin2 and 53-t2 side by side. The image shows there appears to be some change beyond loss of detail, possibly a L-R shift in the front.
- DTI-baseline -> 53-t2 = lin3
Middle is clearly matched, coronal slices look okay, sagittal shows DTI distortions remain.
- 53-t2 -> DTI-baseline = lin4
Brainstem and cerebellum matched well, normal DTI distortions still present.
Rigid
- 53-t2 -> 31-t1 = rig1
- rig1 -> 53-t2 = rig2
Significant blurring, but every feature is in it's proper place.
- DTI-baseline -> 53-t2 = rig3
Brainstem aligned, normal DTI distortions present.
- 53-t2 -> DTI-baseline =rig4
Similar.
Deformable B-spline
- 53-t2 -> 31-t1 = Bspline1
- Bspline1 -> 53-t2 = Bspline2
Superior frontal enlargement, odd upward shifting in rear of brain, distortions everywhere.
- DTI-baseline -> 53-t2 = Bspline3
Fits the cortex on the baseline to the skull on the t2. Retry with a skull stripped t2.
- DTI-baseline-masked -> 53-t2-masked = Bspline4
Bad registration, numerous deformations, midline shift in frontal lobe, right side deformations, cerebellum doesn't fit any more.
Diffeomorphic Demons
- 53-t2 -> 31-t1 = Demons1
- Demons1 -> 52-t2 = Demons2
Multiple deformations. Much larger ventricles. Small errors everywhere, expansions, contractions, shifts. Roughly in the same place overall.
Register Volumes Module
- 53-t2 -> 31-t1 = init1
- init1 -> 53-t2 = init2
Initial
Huge shift in count values, rigid translation down ~4 pixels, left ~1 pixel.
Rigid
Huge shift in grey values. Few other problems.
Affine
Again, shift in grey values, mostly okay otherwise. Slight rightward shift.
B-Spline
Again grey values shift. Minor distortion in frontal lobe and cerebellum.
- DTI-baseline -> t2
TAKES FOREVER. Inferior frontal, temporal, stretched downwards. Cerebellum is terrible. Very top of the brain is stretched. Pretty bad overall.