Our Experience with V8.0 (Elekta)

So, Beam Guide, we are currently using on the majority of our patients, and we have it on all of our systems. I’m just going to talk about the benefits for the different sites. What Beam Guide is, it’s an additional setup tool. So alongside Postural Video, your deltas, and your deformation, you also have Beam Guide. And what Beam Guide does is it gives you a real-time beam projection. I’m sure we’ve all heard of DoseRT, which gives you what you’ve treated because it collects the data after treatment using Cherenkov imaging. What Beam Guide does, it gives you a visual representation of where you’re going to treat before you deliver the radiation.

The real-time projection is a visualization of planned radiation fields. You can either have individual fields, a combination, or a VMAT arc, and you can switch them on and off as you need to. What we’ve found is, for the breast patients, we’ve tended to use all the beams together because it gives you your entry and exit for the whole of your treatment, so you can see what’s going to be delivered through all the static beams. As I say, it helps you detect and prevent errors before the radiation is delivered. Because it’s a live patient surface, the white outline is where your beam should be, and the orange is actually your patient. So what you’re really looking to do is to get that orange projection within that white outline, and then you know you’re treating in the correct area. It’s a real-time projection, and they’re available both for treatment patient setup and during treatment to monitor.

One of our radiographers coined it as having tattoos without tattoos, which I thought was a quite good explanation. So if you get your deltas all into position and you find it looks like your orange is slightly out of the white—say if it was over onto the contralateral breast—as you roll your patient, the orange moves within the white outline. It’s like when you used to roll your tattoo towards your beam edge. So that’s a good phrase that we’ve coined: having tattoos without tattoos.

One of the major benefits of this is, for anybody that’s got AlignRT already, you can get your Postural Video on, you can get your deltas on, and you can check your splash on your fields when you’re setting up your patient. But sometimes what you may not see is if your patient has dropped their chin into the field, especially when you go out of the room. What the system allows you to do, because you are actually seeing the beam and the dose that you deliver into patients, if the patient dropped their chin, even though your deltas and your Postural Video are still, then you would be able to see that you are treating the chin. Similarly, you would be able to see splash onto the contralateral breast, and you would be able to see splash into the armpit if you’re not treating that area.

When we brought the system in, one of the radiographers said to me, “What does it do?” And I said, “Well, we can remove the skin views.” And they were on board straight away because it’s quite faffy going between the Mosaiq screen, finding your screen with your skin views, then going back over to the patient and checking. Also it’s a remote image—you’re looking at something on a screen and then walking back to your patient, and then walking back to the screen and saying, “Is that correct? Do we match our skin views?” Whereas with the Beam Guide, you are actually seeing a real-time visualization of those beams on the patient. So it can speed up your workflow because you’re not having to go in between.

We have noticed that it can aid us with trickier setups. We did have a patient that was scanned with bolus, so they didn’t have a non-bolus setup surface, and they were having problems setting the patient up every day. Halfway through treatment, we brought in the Beam Guide onto that machine, and we found that we could set that patient up a lot easier using the Beam Guide, even though we didn’t have a surface without bolus on. Now, I can’t get to the bottom of why that made that setup easier, but it did make the setup easier.

Also, one of the other advantages that we did find is that an FCL came out a while ago about treating through the join of the bed. What we get our radiographers to do, especially for our pelvis patients and our thoraxes, we will ask them to take the gantry underneath the bed and center the field to make sure that at no point would any of our beams be passing through that join in the bed. What the radiographers have found is that when they’ve been setting up any lower thorax patients or pelvis patients, because you are seeing the whole VMAT arc and you can see it on the bed, you can see straight away if you would be treating through the join of the bed. So you can rectify that before you start treating the patient. But then similarly, again, you’re not having to add on that extra time of taking the gantry underneath and centering the field to check if that’s going to be an issue.

I’m just going to play a quick video of how Beam Guide works. I was going to do a video with one of our patients, but I couldn’t get permission from anybody, so I’m just going to show you this now. I’m just going to get it to the right place. There we go, I think we’re about there. Can you see that? Lovely.

As you can see on this live feed, you’ve got the white outline, and then you’ve got the projection of the beam. This is on the video tile of the AlignRT screen, and you can still flick between your three treatment cameras. So as you can see with this patient at the moment, using the postural video, the deltas, and the Beam Guide to get the patient into position, as you can see, the orange falls within the white.

Then there’s another visual representation here. You can see that the Postural Video is good, you can see the deltas are good, but the patient’s dropped their chin in. So had we not had the Beam Guide, you may not have seen that the patient’s chin was getting radiation dose.

So this was just back to the different benefits that we’ve seen for the different treatment sites. For our breasts, you can check splash on the chin, splash onto the contralateral breast or the arm, and also bolus misplacement. Because you’re able to see the beam when you put the bolus on, you can check that your whole beam is covered by the bolus.

For our DIBH workflow, you do see the beam on both the free-breathing surface and the breath-hold surface. That is worked out by the system so you can check your patient is in the right position. Although it wouldn’t be the treatment beam on the free-breathing surface, you can use all those tools to be able to check that you’re in the right position, and then when you switch over to the breath-hold surface, you then do have the beam on the breath-hold surface to check you’re in the right position.

For our pelvis and thorax, as mentioned earlier, you can visualize if you’re treating through the join of the bed, and it also helps with our supine positioning, especially on patients that would have very sloped chests where maybe the ROI can’t be seen because the cameras can’t visualize it. Having the supine extent of the treatment beams on the VMAT arc helps you to position the patient.

We have found this has been really helpful when we’re setting up our palliative patients. And I did mention earlier about the difficult case of the patient scanned with bolus where there was no body for setup; the Beam Guide helped us to set up that patient a lot easier once we switched it on.

Just on this next slide, I’ll make a bit of a caveat that someone forgot to get the screenshot before the Beam Guide was in position. On our single-pulse patients—I don’t know if anybody else experiences this—when you’ve got patients that are quite rotund or barrel-chested, sometimes once you go to 100 at the back of the bed, your ROI sometimes can’t be fully picked up by the cameras. That’s just a patient issue because of the patient size or where the treatment site is. On imaging days, that’s absolutely fine because you’re imaging and you know you’re in the right position. But we did find that sometimes our radiographers felt a little bit twitched on a non-imaging day because they were like, “We trust the SGRT system, but we’re missing this little black hole.” When we got the Beam Guide and switched it on, we found that the hole was in the ROI because you had the Beam Guide, and the treatment field wasn’t necessarily in the whole of the ROI where you would have the white outline of the beam. So if you couldn’t fully visualize your ROI, you used it to set up. As soon as you switched the BeamGuide on, you could see that the orange projection was within the white outline, and you knew your patient was in the right position for treatment. They were more confident once we got this that on non-imaging days we were in the right position for treatment. As I say, spot the mistake: someone hadn’t moved the lung, so the orange isn’t within the white, but that is what I would have liked to have shown you.

As you can see, there’s lots of really good applications of using the Beam Guide for troubleshooting, setting up the patients, and picking up any errors before you actually deliver any radiation.

*This transcript has been AI-generated. Contact us at secretary@sgrt.org if there are any issues.