Time Savings and Efficiency with SGRT

Some disclosures before I begin. I’ve trained and been employed only with UW Health, so all of my clinical knowledge and experience is from this one institution. My experience with SGRT is primarily with AlignRT system with some work with Identify, and I have no financial gain presenting to you today.

A little bit about me. My name is Mary Slagle. I graduated from University of Wisconsin-La Crosse with a bachelor’s in July of 2024. I completed three years on campus and then a 13-month internship at University of Wisconsin Hospitals and Clinics in Madison, Wisconsin. I was fortunate enough to get hired on after in August of 2024. So I’m coming up on two years later this summer. At UW Health, we have two main clinics and one satellite clinic, and that includes five TrueBeams, STX, one Edge, a TomoTherapy, and a ViewRay system. We use AlignRT with all our TrueBeams and the Edge. We do not utilize in boar with TomoTherapy.

Outside of work, I like to go golfing, avid reader. I also work at Texas Roadhouse part-time, and then I also really enjoy painting our pediatric masks, and I’ve done a couple adult ones as well. This is my favorite I’ve done, but I do get a lot of requests for cats and dogs, and then I’ve gotten a half unicorn, half tiger, so a little bit of everything.

Today, I’m going to focus on the postural video tool and how that helps with efficiency and accuracy of treatments, go into an overview and then more specifics, and then different area for body areas for treatment as well.

Postural video is a tool within AlignRT system. It’s a live video feed that allows you to compare daily setup, compared to a reference position that’s acquired at simulation. AlignRT is the only SGRT system with postural video with over 3,000 users of this tool. So when you bring up a patient for a treatment, there’s the three toggles on the bottom, surface, and then on the end, video. Your surface is your ROI. On the screenshot shown here is your video. So that pink outline or body contour is created off your simulation scan. So that will start and stop depending on your scanning parameters.

So when you’re at simulation, it’s important to think about what the parameters the doctor’s ordering and what you need for treatment planning, but also what might be helpful as a therapist for setting up a patient. So for example, for breast patients, I like to scan a little bit higher to get more towards the elbow for the arm positioning. Might not necessarily needed for treatment planning, but for the arm positioning at treatment is really helpful.

When talking with one of the physicists at UW Health, he explained UW Health got Align back in 2016. It wasn’t really well received by the therapist, but when version six came out with the postural video, they did a trial run and the therapist had overwhelming positive feedback to provide, so management decided to continue vesting in this tool. I personally have never worked with Align without the postural video. Just thinking about it, I know my daily workflow and therapy career would look a lot different without it.

One of the main positives of having this tool is the enhanced visualization it provides. There’s three different angles that you can view the patient from. If you think about it, the ROI is only tracking the area that you’re selecting around the iso-center, but being able to view the patient as a whole just gives us a lot more information.

So one example, on the new start days, you don’t have your saved couch parameters to load the patient into treatment position. A lot of times, we have one therapist holding the pendant, driving the couch, and then we have another therapist that’s toggling through these views using angles one and two to visualize your longitudinal and vertical, and then angle three to visualize your lateral. It just helps with efficiency on those new start days. It’s also very helpful when the patient is in index. So at UW Health, a lot of our patients aren’t. They’re in a mattress or on a mold, and so depending on the day, they could lay higher or lower compared to your saved couch parameters. So our ROI, it’s not tracking at our saved parameters. We switch to the video, and then we can see our longitudinal is off. I’ve gotten to the habit, and a lot of my colleagues have gotten to the habit of just checking your ROI and then automatically just switching to the video just because that’s a double-check for our position. You have your deltas, and you can double-check it with the video and just give us a greater view. When stepping outside of the room, it also just gives you more angles for gantry clearance and patient safety. Some of our treatment consoles only have two cameras, so this is three more views that I can see the gantry clearance around elbows. It’s also really helpful when you’re using Align for your gating system. We’ve run into it where a free-breathing and their breath hold are very similar, so our breath hold capture might be selected, but their free-breathing is still within the deltas and their tolerances. So we’ll put in alerts for patients to turn on the video, and so we can just watch the patient accordingly in the breath hold and beam on and off when needed.

There’s been several studies on the efficiency and accuracy when using postural video. In general, SGRT alone saves 22% of time per fraction. When you add in postural video, it can reduce an additional 25 to 40 seconds per a treatment. First one, for right-sided breast cancer, there is 26 patients in this study, and they were all free-breathing. When SGRT was used alone, setup time was 115 seconds. When adding in postural video, it was reduced to 75 seconds, so that’s a reduction of 40 seconds in setup time. They also took an average of just overall treatment time when the patient was brought into the room and leaving, and it was a reduction of 36 seconds overall, which is pretty synonymous with that setup time.

A little bit larger scale of a study. It was between two sites, similar case loads. One site used SGRT alone. The other site used it with postural video. For all different body areas, on average, it was a reduction shown of 24.6 seconds of reduction time. They also took into account re-imaging rates. That was reduced with postural video by 63%, and also waiting room time. Both of these studies did not show improved accuracy rates, but it did maintain the accuracy that we’ve known to have and kept that standard while increased efficiency and reducing time. There was one study. It was 156 patients for left-sided breast cancer, all in a breath hold. They used their cone beam CT shifts to create their data, and there’s increased accuracy, most significantly in the longitudinal and vertical directions, while a little bit in the lateral as well. And just thinking about, as a therapist, majority of our treatments are in 15-minute time slots. So if we can reduce that time for the patient, it increases patient satisfaction, but also reduces the stress on the therapist on keeping those treatment times applicable.

So this patient, it was a prostate. He was on a mattress. Most of our prostates are on a mattress in a mold on indexed. So using views one and two to visualize your longitudinal for landmarks using your umbilicus and then your inguinal creases. Typically, we scan from L1 to mid femur for prostates. So the inferior border of the outline is maybe cut a little bit short, but we still have a lot of information we can use. The setup time reductions that I have listed on these slides are from the second study that I talked about, just breaking it down by body area.

Extremities are one area that I really highly recommend using postural video. This patient was in a mold. We were treating their ankle. I do feel the mold was built up well around the ankle, but that didn’t allow the ROI to read the roll and pitch really well. So the first couple of days, we were re-imaging, but when we were really diligent, especially in view two, looking at the arch of the foot and the toes and making sure the patient was flexing their foot appropriately minimized our pitch shifts. And then looking at the toes in view three for the roll as well. Other just lower extremities, being able to see the knee joint, especially if there’s cushions underneath the knees, just to visualize the flexion of that.

This was an upper extremity. So the second study, one of the sites didn’t have any extremities during the time of the study, but they had previous data, and it showed a reduction of 60 seconds of setup time for an upper extremity specifically. This case was a palliative case. They were just on a mattress, but indexed on a base plate underneath their head. But they were just holding an O-ring on their chest. So really, any given day, they could hold the O-ring higher or lower, and without postural video, we would not be able to visualize the flexion of their elbow or placement of their forearm or upper arm. So we can manually move the patient’s grip on that, as well as some patients, we just place a towel across their abdomen, and they’re holding onto it on the sides if arms are down, and so we can adjust the grip on the hand on the towel that way.

Here we were treating a shoulder, so especially being able to visualize the shrug of the shoulder. Some patients might be really tense at simulation or on their first day and kind of relax over time, so we can make sure the shoulder shrug is accurate as well.

Here we are treating esophagus. The reduction time is for chest or lungs, but the ROI tracking is pretty similar. This is a great example of when the whole picture matters than just the ROI. Because of the treatment angles, there was a chin block placed, so we had alert from dosimetry and physics that the chin placement had to be at the same level or higher than it was a simulation. So now for setup, we can be accurate and precise with the chin position rather than just having the patient raise their chin up, but the ROI deltas wouldn’t be telling us that information. And when we step out of the room, if they tend to get tired, we can remind them to bring that chin position up into an accurate place. This patient also had a very sloped ribcage, so that was a great marker for our longitudinal and vertical and just any area we’re treating. Everyone’s anatomy is different, so using that to your benefit.

Right now at UW Health, we only use open face masks with SGRT for SRS cases, but we are moving to use them for brain and head and necks in the near future. But prior to putting the mask on in views one and two, using the chin and the nose position to manually move the patient for pitch and then in angle three for roll. You can also use the alignment from the nose to the chin for your yaw positioning as well. And then once you place the mask, it’s best seen in angle three, but you can use the outline of the mask on the forehead and the cheeks to verify placement of that.

Prone breasts with SGRT are different in itself because at least at UW Health, we’re tracking the back rather than the breast we’re treating. Most helpful is view two for this one. Usually, the breast tissue is a great example for your vertical placement. This case was a bit different because the breast was so pendulous it’s actually resting on the table. So if we verified positioning with the arm or the skin creases, and we knew they’re on the board correctly, sometimes the breast tissue would be superior or inferior compared to the outline, so we would manually move the breast tissue for that one.

Here, we’re treating a right chest wall. Arm positioning, as we all know, is very important for any breast treatment, especially if we’re treating different nodal volumes. Having enough of the arm position to have the outline and be able to move the arm up or down accordingly to match the outline is really helpful, along with the chin position, turning away from the breast we’re treating. Having the outline as well for the breast tissue is just another indicator of correct placement, but it also can be if everything else is looking good, maybe the outline isn’t matching the breast tissue, and that can be an indicator for swelling, or maybe they’re really swelled at simulation and now it’s reduced once we come to treatment. I want to point out the reduction of setup time for this study, 36 seconds, is very close with the reduction for the free-breathing right breast of the first study I talked about with the 40-second reduction time. So those two are very comparable.

One application you can use with partial video is when you have the ability to save SGRTs for future use. So at the top, I have our simulation scan versus a SGRT we saved. It provides more information after that first day of treatment. So saving your couch parameters after the doctor looks over the image, saving an SGRT for future use. When you are doing this, just recommend having the area as clear as possible to prevent any outlines that necessarily aren’t needed. Having the gantry at zero, imagers are fully retracted, any extra blankets and towels out of the way, and then capturing when there’s minimal shifts. So if you do have any big rotations, I would recommend manually moving the patient, re-imaging, or just waiting for a subsequent day when the shifts are smaller. We want to keep the integrity of our simulation capture as much as possible. If you are recapturing several times, I just recommend going back to your simulation since that is what we’re trying to reproduce each day. If you do have a blanket at her lower abdomen, so it does create that outline. But for this case in particular, it also captured the bolus outline, which was helpful, which wasn’t present at our sim. Again, waiting till a day to have that bolus placement exactly where you want it to capture for future.

So a benefit to being able to do this is how I mentioned sometimes we scan higher at simulation for the arm position. Now, we could keep our parameters, minimizing dose at simulation just for what we need for planning, and now it gives us more information with saving the capture for future use. And I just wanted to show an example of when the gantry was in that capture in the lower corner. Just creates a lot of mess that’s not needed for setup.

 

 

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