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From: Armanda Heijneman on 29 Mar 2010 08:49
"Vito Marangelli" <vmarangelli(a)libero.it> wrote in message <ef28d74.-1(a)webx.raydaftYaTP>...
> Hi, everybody!
> I am a cardiologist from Italy (thus, I do not undestand Matlab as
> you guys!), and I am trying to read images from three-dimensional
> ultrasound data (specifically produced by an echocardiographic
> machine like Sonos 7500 by Philips) in a format not publicly known
> (maybe DICOM!). I have a good knowlewdge of the Image Processing
> Toolbox, but I don't have information about the data structure of
> Sonos' 3D images!
> Can somebody help me?
> I know that this procedure can be done! As a matter of fact it is
> implemented in a research software utilized in the following paper:
> Watanabe N et al. Geometric differences of the mitral valve tenting
> between anterior and inferior myocardial infarction with significant
> ischemic mitral regurgitation:etc, Journal of the American Society of
> Echocardiography, 2006:19:71-75), see Pubmed for details,
> (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16423672&query_hl=6&itool=pubmed_docsum).
>
> Thanks in advance!

Hello,

I have the same problem, only a few years later :-).
I have real time 3D ultrasound images of the human heart. These files don't have .dcm as extension, I don't know if that is important, since by using >dicominfo I do get the dicomheader.
With the command >dicomread I get an image, but this looks more like a screenshot, it has a size of 768x1024x3 uint8, thus there are actually 3 images, but these are pretty much the same.
Now I do have a program that is able to read in the dataset, so I know it is in the file somewhere, I just can't find it I suppose.

Does anybody here know how to read in 3D ultrasound images?
Or is it just too hard for MATLAB, since it is actually a whole lot of data (but I guess it is still stored as a 3D matrix), but then again, the article quoted by Vito did succeed in reading in the files.

I hope somebody can help me!
From: Lead Bucket on 22 Apr 2010 14:24
> Hello,
>
> I have the same problem, only a few years later :-).
> I have real time 3D ultrasound images of the human heart. These files don't have .dcm as extension, I don't know if that is important, since by using >dicominfo I do get the dicomheader.
> With the command >dicomread I get an image, but this looks more like a screenshot, it has a size of 768x1024x3 uint8, thus there are actually 3 images, but these are pretty much the same.
> Now I do have a program that is able to read in the dataset, so I know it is in the file somewhere, I just can't find it I suppose.
>
> Does anybody here know how to read in 3D ultrasound images?
> Or is it just too hard for MATLAB, since it is actually a whole lot of data (but I guess it is still stored as a 3D matrix), but then again, the article quoted by Vito did succeed in reading in the files.
>
> I hope somebody can help me!

Armanda,

I believe the issue is that if 'dicomread' doesn't find an offset table at the beginning of the image data, then it automatically assumes that there is only one image frame. This seems kind of silly considering that the "metadata" created during the dicomread function contains a parameter called NumberOfFrames, although I haven't looked into how this parameter is determined.

I too work with ultrasound data, and for some reason, our scanner will output DICOM both with and without this offset table. I had to modify 'dicomread' to check if no offset table existed AND multiple frames existed, then load the frames based on the size of the previous frame (since my data was compressed).

The reason you get a 768x1024x3 uint8 dataset is because you are given the RGB version of the first frame. Your full data set should be 768x1024x3xnum_frames of uint8 data. If you use 'image' on your dataset, you'll have the image of the first frame in your dataset. If you are expecting to be able to manipulate 3-D data though, you can forget about that. The ultrasound manufacturers output the screen image only, so you can see the 3-D rendered image from frame-to-frame, but you won't be able to rotate the object and observe it in 3-D, as far as I know.
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