SGRT Forum

Hi there,

I'm wondering if someone with experience of Align RT Advance could help me out. We are looking to install the system and I'm just curious about the operation of the Postural Alignment component. In particular I'm wondering what defines the postural alignment outline - is it the body structured generated from CT or is it generated from reference captures during treatment?

Thanks in advance,
Conor

Conor,

From what I heard from our trainer on go-live was that it uses the body, but makes a more comprehensive/accurate outline during reference capture. After using it for a few months, I can confirm that this is what I've noticed. The CT-generated one will occasionally have some issues with it (discrepancies when switching between the different cameras), but more often than not it is adequate when using it for breasts in order to view the arm position in conjunction with the deltas. Hope that helps

Hi,
I presume your question is about the initial set up for free breathing patient with or without tattoo. In other word you would like to know what to use for the patient set up on the treatment couch at the first fraction and what to use for the subsequent ones. Is it the body structure set generated and exported from the TPS OR the reference surface that can be captured by the Align-RT camera? I hope I have got this right!

In fact the body structure set will have to be utilized as the first aid to setup the patient followed by the kV/MV/CBCT imaging alignment. The Body contouring alignment gets the patient very close to the right treatment position, which is verified or corrected within the imaging process. As soon as this step is completed, a reference surface can be captured and then utilized for the rest of the treatment course, while a reduced frequent imaging regimen is applied to regularly validate the reference surface. The reference surface may be changed during the treatment course if the imaging process suggests so.
I hope this helps.

Hi All,

Just to clarify, the outline is automatically generated using information from within the reference surface. That reference surface can either be the DICOM surface from CT or it could be a reference capture (whichever one you are using at that time) This information along with information from within the raw images from the cameras is used to create an outline using edge detection techniques.

I hope this makes sense, please feel free to ask if you need any further clarification on this.

Many Thanks

Elise

Thanks for all your detailed responses! I was curious if we would need to scan more of the arm at CT but since it uses a combination of the CT data set and the reference captures, that doesn't seem to be necessary. Looking forward to trying it.