[Insight-users] MR Object Extraction and Registering with SPECT.

[Luis Ibanez]

Hi Srivalli,

Did you verified if the coarse levels of the
pyramid are converging ?

If you find that they are using all the alloted
iterations, that means that they have not
achieved conversion.

Please tune one level of the pyramid at a time,
starting of course with the coarse levels.

BTW: The translation scale value that you are
using seems to be extremely large for a Brain MR
image. I would assume that your image has an extent
of about 300 millimeters (for a typical human skull),
your scaling seems to be set for an image of 100.000
millimeters in linear extent.


   Regards,



       Luis


-----------------------
valli gummadi wrote:

>  Hi,
>  
>       I am working on Registration of Single and Multi modality images. I am facing problem in registering multi modality images.
>  
> Let me explain the procedure and steps I followed to process multi modlaity images.
> 
> Registration of MR and SPECT images:
> 
> 1.MRimage will be in CORONAL view and SPECT will be in Transverse view.
> I converted the SPECT to CORONAL before giving it for registration.
> 
> 2.Actual requirement is to extract the Brain object from the MR and to register that object with the spect. I extracted Object from the MR using itkNeighbourhoodConnectionImageFilter and used the exctracted brain as Fixed image and Registered MROBject with SPECT.
> 
> 3.The registered spect is transformed and fuse it with the original MR so that spect fuses with the brain and not with the other tissues.
> 
> I am  using following itk classes for registration and transform 
> proces:
> 1. MultiResolutionImageRegistrationMethod
> 2.MattesMutualInformationImageToImageMetric
> 3.LinearInterpolateImageFunction
> 4.RecursiveMultiResolutionPyramidImageFilter
> 5.CenteredAffineTransform & centered Affine Transform Initializer
> 6.RegularStepGradientDescentOptimizer
> 7.ResampleImageFilter
> 
> no of iterations =450;
> TranslateScale =1000000;
> optimizer Scales =1;
> Optimizer maximum step length =16;
> Optimizer minimum step length =2.5;
> SpatialSamples =1000;
> Bins =50;
> No of Levels =3;
> SetMinimize =TRUE;
> 
> 
> After fusion, I observed that SPECT is not exactly alighned with brain object of the MR Volume.
> Please,Anybody help me to implement the registration to acieve the expected output.
> 
> Thanking You,
> Regards,
> Srivalli.
> 
> 
> 
> 
>