[Vv] Errors with clitkExtractLung

Rômulo Pinho romulopinho at yahoo.com.br
Wed Oct 23 22:41:09 CEST 2013


Hello, Bilal,

I'd have to verify this (maybe Vivien can also comment on that), but I 
think the dir-lab data are not in HU, i.e., the grey values are all 
positive, from 0 to 4096. The algorithms in clitkExtractLung apply some 
thresholding operations that depend on a data set in HU, roughly from 
-1024 to 3072.

To cope with it, you can either play with the parameters 
seedPreProcessingThreshold and upperThresholdForTrachea in 
clitkExtratLung (depending on TYPE)
"upperThresholdForTrachea"    -    "0: Initial upper threshold for 
trachea"  default="-900"
"seedPreProcessingThreshold"   -  "1: Threshold for the pre-processing 
step of the algorithm" default="-400"

or, to be on the safe side, shift your grey values prior to launching 
clitkExtractLung. You can do it by creating an image with -1024 
everywhere (clitkCreateImage does the job) and then applying the shift 
by adding the two images with clitkImageArithm.

In any case, using --verboseRG might also give some extra insights.

I hope this helps!

Best,
Rômulo

On 23/10/2013 14:15, Bilal Tahir wrote:
> Thanks Vivien,
>
> I've got passed the .afdb stage. However I'm getting errors at the 
> 'search for trachea' stage for both the original and LOLA11 
> algorithms. The dataset is the inspiration scans for patient 1 of the 
> dir-lab copd data.
>
> 1) LOLA 11:
>
> [md1bat at testnode02 mhd]$ clitkExtractLung --verboseStep 1 -i 
> copd1_00.mhd -a default.afdb -o 00_lungs.mhd --type=1
> Step 1 -- Copy and crop input image to 'patient' extends
> Step 2 -- Set background to initial image
> Step 3 -- Remove Air
> Step 4 -- Search for the trachea
>
> itk::InvalidRequestedRegionError (0x2bca660)
> Location: "unknown"
> File: /home/md1bat/Source/itk/Modules/Core/Common/src/itkDataObject.cxx
> Line: 411
> Description: Requested region is (at least partially) outside the 
> largest possible region.
>
> 2) Original (type=0)
>
> [md1bat at testnode02 mhd]$ clitkExtractLung --verboseStep 1 -i 
> copd1_00.mhd -a default.afdb -o 00_lungs.mhd --type=0
> Step 1 -- Copy and crop input image to 'patient' extends
> Step 2 -- Set background to initial image
> Step 3 -- Remove Air
> Step 4 -- Search for the trachea
>          The volume of the trachea (4035.53 cc) seems not correct. I 
> skip some slices (0) and restart to find seeds.
>          The volume of the trachea (4037.01 cc) seems not correct. I 
> skip some slices (5) and restart to find seeds.
>          The volume of the trachea (4036.86 cc) seems not correct. I 
> skip some slices (10) and restart to find seeds.
>          The volume of the trachea (4036.39 cc) seems not correct. I 
> skip some slices (15) and restart to find seeds.
>          The volume of the trachea (4036.07 cc) seems not correct. I 
> skip some slices (20) and restart to find seeds.
>          The volume of the trachea (4035.31 cc) seems not correct. I 
> skip some slices (25) and restart to find seeds.
>          The volume of the trachea (4035.54 cc) seems not correct. I 
> skip some slices (30) and restart to find seeds.
>          The volume of the trachea (4035.49 cc) seems not correct. I 
> skip some slices (35) and restart to find seeds.
>          The volume of the trachea (4035.39 cc) seems not correct. I 
> skip some slices (40) and restart to find seeds.
>          The volume of the trachea (4035.57 cc) seems not correct. I 
> skip some slices (45) and restart to find seeds.
>          The volume of the trachea (4035.69 cc) seems not correct. I 
> skip some slices (50) and restart to find seeds.
>          The volume of the trachea (4036.09 cc) seems not correct. I 
> skip some slices (55) and restart to find seeds.
>          The volume of the trachea (4036.34 cc) seems not correct. I 
> skip some slices (60) and restart to find seeds.
> 2 : Number of slices to skip to find trachea too high = 65
>
> itk::ExceptionObject (0x377f970)
> Location: "Unknown"
> File: /home/md1bat/Source/vv/segmentation/clitkExtractLungFilter.txx
> Line: 266
> Description: No seeds for trachea... Aborting.
>
> 3) Manually setting a higher number of slices than 65
>
> [md1bat at testnode02 mhd]$ clitkExtractLung --verbose 1 -i copd1_00.mhd 
> -a default.afdb -o 00_lungs.mhd --skipslices=90
> Input is 3D short.
> Reading [copd1_00.mhd] ...
> 2 : Number of slices to skip to find trachea too high = 95
>
> itk::ExceptionObject (0x3a379d0)
> Location: "Unknown"
> File: /home/md1bat/Source/vv/segmentation/clitkExtractLungFilter.txx
> Line: 266
> Description: No seeds for trachea... Aborting.
>
> As you can see, I keep failing at the search trachea stage even by 
> trying various different options for slices to skip for the trachea. 
> Please let me know if you have any suggestions that can help.
>
> Best wishes,
>
> Bilal
>
>
> On 23 October 2013 16:51, Vivien Delmon 
> <vivien.delmon at creatis.insa-lyon.fr 
> <mailto:vivien.delmon at creatis.insa-lyon.fr>> wrote:
>
>     On 10/18/2013 12:08 AM, Bilal Tahir wrote:
>
>         Dear VV community,
>
>         ...
>
>
>         Also I would like to know if the LOLA11 paper below is the correct
>         reference if I decide to use your method for publications?
>
>         http://lola11.com/Results/displayApproved?result=20110708160218_86_CREATIS_CLB_Lyon_graphcut&file=20110708160218_86_CREATIS_CLB_Lyon_graphcut_lola11.pdf
>
>
>     Part of the work presented in this paper have been implemented in
>     clitkExtractLung but you need to explicitly ask the tool to use it :
>
>     Step 2 : find trachea:
>       --type=INT trachea finding algorithm (0: original; 1:LOLA11)
>     (default=`0')
>
>     The second part about graphcut labeling were not included in this
>     tool since we never really need to separate lungs.
>
>     Last time I tried to activate --type=1 it failed, I will have a
>     look at it one day.
>
>     As far as I know there is no other paper that describe what we
>     have implemented in this tool, so this paper should be the one to
>     cite.
>
>     -- 
>     Vivien Delmon
>     PhD student at CREATIS, Lyon
>     Supported by ANRT and ELEKTA
>     http://www.creatis.insa-lyon.fr/rio
>
>     _______________________________________________
>     vv mailing list
>     vv at creatis.insa-lyon.fr <mailto:vv at creatis.insa-lyon.fr>
>     http://www.creatis.insa-lyon.fr/mailman/listinfo/vv
>
>
>
>
> -- 
> Bilal Tahir,
> James Morrison Researcher in Radiotherapy Imaging,
> Department of Clinical Oncology,
> University of Sheffield
>
>
> _______________________________________________
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> vv at creatis.insa-lyon.fr
> http://www.creatis.insa-lyon.fr/mailman/listinfo/vv

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