The direction of x and y jaw position in Beams Module

Support
1

Slicer version:4.8.1
Hi 3D slicer experts and all
In Beams module for Geometry Tab, the x jaw position and y jaw position are in the direction of which axes respectively? In the other words SI or AP or RL axes?
Thanks a lot

2

In general, in Slicer, first (x) axis is L-R, second (y) axis is A-P direction. @cpinter or @gcsharp may comment on the axes directions in this specific case.

Use latest stable version (Slicer-4.10).

3

Hm, it looks like the beams module does not follow IEC conventions. Thank you for the alert.

1 Like
4

I fixed the issue as discussed with @gcsharp, see https://github.com/SlicerRt/SlicerRT/issues/100.
It should be fine in tomorrow’s nightly or later (but NOT in 4.10, only in 4.10.1 when released).

5

Hi
Thank you for your guidelines.I have another question ! I import the RT Plans from Treatment Planning System (TPS). In TPS, the x is in L-R and y is in S-I directions. Is it possible to match the x and y directions in these two systems (i.e TPS and 3D Slicer)?
Thanks a lot

6

We talked with @gcsharp and although the axes were right after my fix, the directions weren’t. I fixed them now.

To use this fixed version, please install the “Nightly Build” tomorrow or any day after: https://download.slicer.org/

7

Hi Azam,

Now everything should match between Slicer and your TPS after Csaba’s fix (tomorrow or next day nightly build). For gantry 0, couch 0, and HFS treatment position, you should see x increase from R to L, and y increase from I to S. Please let us know if you have any more problem and thank you for your report.

8

Hi 3D Slicer experts and all
I’ m sorry for my question .but can you tell me that for gantry 0 and collimator 0 , what is the direction of x and y jaw respectively for slicer 4.10.1 (Linux)?
Thanks a lot

9

After our recent fixes, which are included in 4.10.1, everything should conform to the DICOM standard:

  1. IEC: http://dicom.nema.org/medical/DICOM/current/output/chtml/part03/sect_C.8.8.25.6.html
  2. Beams (see jaws at ‘beam limiting device’): http://dicom.nema.org/medical/DICOM/current/output/chtml/part03/sect_C.8.8.14.html
10

Hi
Thank you very much for your guidelines. Briefly , by considering the 3D view and slice viewers , for Gantry 0 and collimator 0 , the x jaw position increases in S-I direction and y jaw position increases in L-R direction. also, both the Gantry and collimator rotation are counter clockwise. is this statement true ?
Thanks a lot