On Friday, March 14, 2008 at 10:15:56 PM UTC+3:30, johnw...@gmail.com wrote:
> Hi all,
> I am trying to better understand the concepts behind DICOM RT-Dose
> objects, and how they should be displayed by viewing applications
> supporting DICOM RT objects.
> What I understood until now (correct me if I am wrong) is that doses
> can be expressed in terms of:
> 1) dose points or isodose curves: in this case, the elements which
> should be displayed by a RT viewer application are described in the
> DICOM dataset through the ROI Contour module, which basically
> describes points, lines or polygons as a set of 3D coordinates in the
> 3D space of the patient.
> 2) does grid: in this second case, the dose values are described
> through the Pixel Data data element. Here, pixel values actually
> represent dose values, correct? A multi-frame Pixel Data attribute may
> be present, and in this case each frame represent dose values for a
> given "plane / slice", as specified by the "(300C,000C) - Grid Frame
> Offset Vector" data element.
> Is my understanding correct until now?
> Ok, now I have a question:
> I have some sample studies where multiple "RT-Dose" DICOM files are
> present, each one having multiple frames in Pixel Data. Considering
> all these RT-Dose DICOM files, I have several RT dose "pixel data"
> frames (coming from different files) which apply to a given CT slice
> (i.e., which belong to the same plane as the CT slice). Should I SUM
> the dose values coming from each RT dose frame which apply to a given
> CT slice in order to obtain the actual dose value which should be
> applied to every pixel of my CT slice? Or how should I combine values
> coming from different RT dose frames which apply to the same CT slice
> (i.e., which have the same Grid Frame Offset value)?
> In particular, I am considering the issue from the point of view of
> the viewing application: I have seen applications which show the RT
> dose which applies to each CT slice as a semi-transparent overlay area
> varying from blue for lower-dose zones to red for higher-dose zones
> (IsoShades). So in this case I guess the viewing application should
> compute the "overall" dose which applies to a given CT slice. How are
> the several RT-dose frames related to a given CT slice's plane
> combined?
> Any clarification would be greatly appreciated.
> Regards,
> John.
Hi Dear John
we need some information about your experiences for RT-DOSE and RT-PLAN
how can convert Ct DICOM to RT-DOSE or the most important questions is how can we calculate the value of dose??
Thanks.
Aram