IMRTP results and showIMDose

184 views
Skip to first unread message

gsayre81

unread,
Dec 19, 2011, 4:47:01 PM12/19/11
to CERR FORUM

Hi,

So it looks like I'm getting reasonable results with my initial foray
into IMRTP-based optimization. However, whenever I load the "body"
structure with showIMDose, I get a flat "purple" plot (ie everything
is very high). Yet when I construct DVH within the CERR viewer,
everything seems pretty reasonable with expected DVH behaviors for all
regions (including "body"). If I don't include the body region then
the plot is also fine. Is there something I'm doing wrong or missing?
Here are my calls:

dose3D = getIMDose(IM,x_opt,structNums);
showIMDose(dose3D,strcat('Dose_Plan',num2str(num))));

Thanks so much,

-George

Joseph Deasy

unread,
Dec 20, 2011, 8:36:11 AM12/20/11
to cerr-...@googlegroups.com
Hi George -

There is an option in CERROptions that tells CERR not to convert a structure into a map onto the regularized 3D grid (the one used for dose calc.)  Probably it is still set to the default, which, if I recall, excludes 'skin' or 'body.'  Check that.  The reason we do this is that the structure mask for body takes up a lot of memory.

Let us know.

- Joe


--
You received this message because you are subscribed to the Google Groups "CERR FORUM" group.
To post to this group, send email to cerr-...@googlegroups.com.
To unsubscribe from this group, send email to cerr-forum+...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/cerr-forum?hl=en.


gsayre81

unread,
Dec 20, 2011, 12:01:57 PM12/20/11
to CERR FORUM

Hi Joe,

I will look into that. Is there a better way to show the 3D dose map?
Would it be better if I just loaded the optimized beamlet weights back
into CERR? Thanks,

-George

ap...@mskcc.org

unread,
Dec 20, 2011, 12:51:41 PM12/20/11
to cerr-...@googlegroups.com
Hi George,

The method you are using to display the IMRT dose looks good. Since the DVHs
showed up correctly and the dose did not, there seems to be something wrong
with the dose display. Did you see any errors on Matlab command window? Did
you look at different CT slices to make sure that the dose is uniform across
all the slices?

- Aditya



=====================================================================

Please note that this e-mail and any files transmitted with it may be
privileged, confidential, and protected from disclosure under
applicable law. If the reader of this message is not the intended
recipient, or an employee or agent responsible for delivering this
message to the intended recipient, you are hereby notified that any
reading, dissemination, distribution, copying, or other use of this
communication or any of its attachments is strictly prohibited. If
you have received this communication in error, please notify the
sender immediately by replying to this message and deleting this
message, any attachments, and all copies and backups from your
computer.

Joseph Deasy

unread,
Dec 20, 2011, 1:01:19 PM12/20/11
to cerr-...@googlegroups.com
Actually, Aditya told me this would not do it.  So we still don't know what the display issue is, I'm afraid.
- J

gsayre81

unread,
Dec 20, 2011, 1:30:50 PM12/20/11
to CERR FORUM

Hi Joe and Aditya,

Thanks so much for responding. First of all, I'm sorry, the info I
supplied you wasn't all correct.

I just exported the DVHs from the real plan (the one used for the
patient) and what I thought would be mine and they were identical. So
maybe my new plan's DVHs are wild since I can't seem to calculate
them. Though, if I can trust the plot (without the 'body' structure
loaded) then I would think they are not, because the max seen is 81,
an expected number, differing only slightly from the real plan max of
80.6.

gsayre81

unread,
Dec 20, 2011, 2:39:10 PM12/20/11
to CERR FORUM

Again, sorry. Please bear with me, I'm still a n00b. I really
appreciate what you guys are doing. I found out the DVH's are going in
correctly, I just didn't know I had to add them to the DVH construct
window to make it happen (sorry). The body dose is still really high.
It seems like even if there was one beam, the max body dose shouldn't
be higher than around 80, yet I'm looking at 220+ with 5 beams.

Aditya, I don't see any errors in the Matlab command window. The dose
profile across the slices is weird. It actually appears to be correct,
ie low for the majority of the body. However, there are 2-3 regions of
really high dose that is outside the axial slices encompassed by the
PTV... really weird. Also, by changing the window, I think I can see
the beams, which all appear to be too hot. The organs appear largely
spared so maybe I just need more constraints on the problem. I will
ask my boss about that. I hope I didn't waste too much of your time.
Thanks so much again,

-George

ap...@mskcc.org

unread,
Dec 20, 2011, 2:48:44 PM12/20/11
to cerr-...@googlegroups.com
No problem George! Just a note of caution: the IMRTP beams were not
commissioned. So the values in dose matrix are correct only in relative
sense. You should normalize with respect to a prescription dose (example:
scale doseArray to make the mean dose within PTV equal to the prescription
dose).

- Aditya

gsayre81

unread,
Jan 4, 2012, 5:16:47 PM1/4/12
to CERR FORUM

Hi Aditya,
What if I am using a quadratic objective for the PTV, but mean and max
objectives for OARs? Is there a normalization procedure for this?
Thanks,
-George
On Dec 20 2011, 11:48 am, ap...@mskcc.org wrote:
> No problem George! Just a note of caution: the IMRTP beams were not
> commissioned. So the values in dose matrix are correct only in relative
> sense. You should normalize with respect to a prescription dose (example:
> scale doseArray to make the mean dose within PTV equal to the prescription
> dose).
>
> - Aditya
>

gsayre81

unread,
Jan 4, 2012, 6:17:59 PM1/4/12
to CERR FORUM
Btw, I did get the max dose in the body down to around 80 (by
inserting a max function for the 'body' structure). However, I am
still getting really weird artifacts, most worrisome are the ones that
seem to be outside the field of view of the beams.

Alexis Beltrán

unread,
Sep 14, 2018, 12:31:31 PM9/14/18
to CERR FORUM
Good morning, I have some issues when I obtain the matrix dose, when I get the DHV my doses dont match with the ones in the prescription of that plan ( I have maximum 5 Gy for some strutures and the plan goes up to 80 Gys in some structures of the official plan) do I need to normalize the values of the dose matrix? How can I do that and next get the new DVH with the new normalized matrix?. Hope you could read me 
Reply all
Reply to author
Forward
0 new messages