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Wednesday, May 14, 2014
Monday, May 12, 2014
Added the "Detect Bright Ridges" function to the User Interface.
Operating volume - user specified increase in the resolution of the resulting "Ridges". It is practical experience that skeletons might benefit from the increase in resolution since their width of 1 voxels is used to simulate the objects of 0-thickness. "Increase resolution coefficient" in practice range from 1 to 3.
Interpolation - specifies the algorithm used in image upscaling.
Background detection is a part of the algorithm. Background is detected by overall smoothing of the volume. User has to specify "Radius (vox)" and the type of the smoothing Kernel.
Output parameter - specifies the result of the processing.
Elevation Map - Signal intensity volume specifying the likelihood that corresponding voxel is a ridge.
Ridge Mask: Binary ROI representing wide ridges.
Skeleton Mask: Centerlines of the Ridges represented as binary volumes.
Operating volume - user specified increase in the resolution of the resulting "Ridges". It is practical experience that skeletons might benefit from the increase in resolution since their width of 1 voxels is used to simulate the objects of 0-thickness. "Increase resolution coefficient" in practice range from 1 to 3.
Interpolation - specifies the algorithm used in image upscaling.
Background detection is a part of the algorithm. Background is detected by overall smoothing of the volume. User has to specify "Radius (vox)" and the type of the smoothing Kernel.
Output parameter - specifies the result of the processing.
Elevation Map - Signal intensity volume specifying the likelihood that corresponding voxel is a ridge.
Ridge Mask: Binary ROI representing wide ridges.
Skeleton Mask: Centerlines of the Ridges represented as binary volumes.
Saturday, May 10, 2014
Friday, May 9, 2014
Thursday, May 8, 2014
GRASP-DCE, patient MH, comparison of K-trans for various ROIs created by Anne
K-trans (1/min)
Using Anne's hand-drawn Using FVX IDF of carotid
ROI (carotid)
1.19 0.84 tu-right
0.97 0.67 co-whitematter-left
0.165 0.11 posttreatment-right
1.163 0.80 co-whitematter left
0.463 0.31 tu-brainstem-center
2.62 1.82 co-brainstem
1.62 1.13 suspectmass - left temporal lobe
>4 3.86 co-greymatter-right
K-trans (1/min)
Using Anne's hand-drawn Using FVX IDF of carotid
ROI (carotid)
1.19 0.84 tu-right
0.97 0.67 co-whitematter-left
0.165 0.11 posttreatment-right
1.163 0.80 co-whitematter left
0.463 0.31 tu-brainstem-center
2.62 1.82 co-brainstem
1.62 1.13 suspectmass - left temporal lobe
>4 3.86 co-greymatter-right
Wednesday, May 7, 2014
Tuesday, May 6, 2014
Monday, May 5, 2014
Sunday, May 4, 2014
Saturday, May 3, 2014
Thursday, May 1, 2014
Wednesday, April 30, 2014
Tuesday, April 29, 2014
Monday, April 28, 2014
Registration defect fixed: while registering two longitudal MPRAGE images, the registration crashes if one of 3 measures is used: {SignalDiff, CrossCorrelation, RatioUniformity}
Added the ABT subtest for sag1.im<->sag4.im registration for 5 additional measures:
{SignalDiff, CrossCorrelation, RatioUniformity,MI,MI-norm}
Added the ABT subtest for sag1.im<->sag4.im registration for 5 additional measures:
{SignalDiff, CrossCorrelation, RatioUniformity,MI,MI-norm}
Thursday, April 24, 2014
Wednesday, April 23, 2014
Tuesday, April 22, 2014
Sunday, April 20, 2014
Implementing highly efficient internal volume codec that is targeting the volumes upsampled using the NN-interpolation. This is a critical function during the PET-4D to MR registration.
User optimally desires best available resolution for both registered volume, which is typically a MR resolution. However, for high timepoint # the resulting volumes might reach upto 7 GB (compressed with the regular FireVoxel compression).
This new codec will allow much higher compression of such registered PET volumes.
It is lossless.
User optimally desires best available resolution for both registered volume, which is typically a MR resolution. However, for high timepoint # the resulting volumes might reach upto 7 GB (compressed with the regular FireVoxel compression).
This new codec will allow much higher compression of such registered PET volumes.
It is lossless.
High-accuracy PET-to-MR registration using an approximate BrainMask with 4X speed gain.
Presently, it is very hard to achieve PET-to-MR registration without additional guidance.
From previous registration experience, a quick Brain ROI was obtained using the BrainMask\EdgeWave tool.
This ROI is just an approximation of an anatomically precise mask of the brain. FireVoxel can obtained a much more precise BrainMask by adding the non-uniformity correction to that workflow.
After obtaining BrainMask ROI, the regular PET-to-MR registration runs that uses ROI as a guidance. Resulting registration has a very high accuracy.
The whole processing is less than 4 minutes on the reference ($1K) PC.
Presently, it is very hard to achieve PET-to-MR registration without additional guidance.From previous registration experience, a quick Brain ROI was obtained using the BrainMask\EdgeWave tool.
This ROI is just an approximation of an anatomically precise mask of the brain. FireVoxel can obtained a much more precise BrainMask by adding the non-uniformity correction to that workflow.
After obtaining BrainMask ROI, the regular PET-to-MR registration runs that uses ROI as a guidance. Resulting registration has a very high accuracy.
The whole processing is less than 4 minutes on the reference ($1K) PC.
Implemented an initial variant of the "Inter-volume Edge Constrained Smoothing". In this test:
a) MR and PET4D were registered with very high accuracy.
b) MR-edges (as 3D surfaces) were detected using the texture-edge detector (URAL)
c) PET-volume was smoothed, with smoothing apperture that was constrained by the presence
of edges within vicinity of every voxel.
This just a prototype as many options are available.
Specialized dialog box was developed.
a) MR and PET4D were registered with very high accuracy.
b) MR-edges (as 3D surfaces) were detected using the texture-edge detector (URAL)
c) PET-volume was smoothed, with smoothing apperture that was constrained by the presence
of edges within vicinity of every voxel.
This just a prototype as many options are available.
Specialized dialog box was developed.
Sunday, April 13, 2014
Completely re-enginered the Sokoloff-79 model (as in Wai's implementation = short formula).
a) Enabling the analytic integration, instead of PWL-functions. This also eliminates the need for the 1-sec upsampling of the TAC data used in the old version.
b) More streamlined and corrected implementation of the Ta-arterial delay.
a) Enabling the analytic integration, instead of PWL-functions. This also eliminates the need for the 1-sec upsampling of the TAC data used in the old version.
b) More streamlined and corrected implementation of the Ta-arterial delay.
Saturday, April 12, 2014
Friday, April 11, 2014
Thursday, April 10, 2014
Wednesday, April 9, 2014
Sunday, April 6, 2014
Updated the IDIF user interface and algorithm:
a) Adding a drop down combo box where user can select the direction {X,Y,Z} of the Vessel.
b) Adding an experimental option {Auto} for the direction of the vessel. In this mode, all 3 directions will be checked and the largest (by voxel count) resulting vessel would be selected.
New features seem to provide a substantial improvement in usability and quality of the result. F.e. in liver, we would like to always work in Axial projection where the Portal Vein direction is often along {X,Y} axis.
So in new version, user does not have to choose the direction of the vessel. So for portal vein the "Auto" direction is set by default.
Another change is that the seed does not have to cover the vessel. Instead, it is only assumed that the center of the seed should be very close to the vessel in question.
a) Adding a drop down combo box where user can select the direction {X,Y,Z} of the Vessel.
b) Adding an experimental option {Auto} for the direction of the vessel. In this mode, all 3 directions will be checked and the largest (by voxel count) resulting vessel would be selected.
New features seem to provide a substantial improvement in usability and quality of the result. F.e. in liver, we would like to always work in Axial projection where the Portal Vein direction is often along {X,Y} axis.
So in new version, user does not have to choose the direction of the vessel. So for portal vein the "Auto" direction is set by default.Another change is that the seed does not have to cover the vessel. Instead, it is only assumed that the center of the seed should be very close to the vessel in question.
Saturday, April 5, 2014
Corrected defect: In all 3D registrations 2 documents should be present. The selected document is used as a Target of the registration. However, if more than 2 document are present, the selection of Source document is sometimes incorrect. Now the warning would be issued when more than one possible Source document is present.
Fixed the defect of gross misregistration in liver DCDI exam. New default setting for all parameters were explored and set. All the gross misregistration cases are fixed. Results are not stellar, but for large proportion of timepoint the movement across the axial plane is greatly reduce.
Further work will be done as needed but result is good enough for now.
Further work will be done as needed but result is good enough for now.
Friday, April 4, 2014
Developing UI function: " MainMenu>Volume>Crop timepoints". This function takes 4D volume.
User specify comma-deliniated set of timepoints such as "1,3,5,7". Function outputs another 4D volume containing only the specified timepoints. This is a very important function for troubleshooting the 4D registration.
User specify comma-deliniated set of timepoints such as "1,3,5,7". Function outputs another 4D volume containing only the specified timepoints. This is a very important function for troubleshooting the 4D registration.
Thursday, April 3, 2014
PET-to-MR registration: Achieved a very good registration result on the difficult case "MG". Problem was that PET image was rotated by 12 degrees with the respect to MR just in one axis Z.
Default registration parameters were "widened" to accommodate such enormous displacements. Also switch default registration measure from MI (mutual info) to URAL (gradients).
Default registration parameters were "widened" to accommodate such enormous displacements. Also switch default registration measure from MI (mutual info) to URAL (gradients).
Wednesday, April 2, 2014
Finalized the algorithm and User interface for the 2 way "PET register to Anatomy" function.
Presently, {PET3D,PET4D}<->{MR3D,MR4D} can be registered. If both source and target are 4D user is given a choice for which one to keep in 4D.
All the additional layers (such as ROIs) are transformed properly.
Presently, {PET3D,PET4D}<->{MR3D,MR4D} can be registered. If both source and target are 4D user is given a choice for which one to keep in 4D.
All the additional layers (such as ROIs) are transformed properly.
Tuesday, April 1, 2014
Monday, March 31, 2014
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