Implementing a Markless Workflow in a Community Hospital

Alexander Pevsner, PhD, DABR (00:04):

So, my name is Alex Pevsner. I am a Physicist at Greenwich Hospital. We are a community hospital, but we are part of the larger network. We are Yale New Heaven Health Network in Connecticut. So I’m going to start with my presentation and background. So in general, community hospitals tend to delay implementation of advanced treatment techniques due to limited resources and staffing. However, in our community clinic, we successfully implemented markless workflow and markless setup, and we use now for all the sites, including advanced cases, SS and SBRT. So my presentation goal is to demonstrate to audience that with a thanks, good that with an efficient preparation, planning, and a teamwork mark was set up. And workflow can be successfully implemented in a setting with even limited resources. So here’s a big picture. Any, anything, any project that you want to implement, we have key steps.

Alexander Pevsner, PhD, DABR (01:16):

So, you start with a motivation and there will be some prerequisites, technical prerequisites, prerequisites you need to meet, you have an implementation plan, and before you go live, you want to do some, some testing. And once you complete all the steps, you do, you go live. So you are enabling new technique as a standard practice in your facility. There is one more step that you would like to do. It’s an optional step, but we did it. And you would like to evaluate your technique and do some sort of a testing. You have some sort of a metrics how well your technique works.

Alexander Pevsner, PhD, DABR (01:59):

So I’m going to start with motivation, why you want to do mark less treatments. So this slide I got actually from the Vision RT website. And it’s a study that was conducted by a non-profit organization called Young Survivor Coalition. And they survey breast cancer women, young women with breast cancer at the age of 40. And one of the questions they were asking is, what are your overall feelings about receiving tattoo as a part of the cancer treatments? And no surprise, 62% have a strong negative response. And moreover, that patients were willing to travel further distance better an extra cause of travel and experience log longer times just to receive a markless treatment. So today, patients prefer to choose facilities that not only address their medical needs, but also their emotional needs. So they want a facility that provides a patient-centric treatment. Okay, so I attended this meeting several times, and also I noticed that a lot of speaker interchangeably use Markus and Ulis definition.

Alexander Pevsner, PhD, DABR (03:14):

So I think that I have my own sort of vision of definitions of it, and I think they’re not the same. So is it a Markus or Aless? So is tattoo free does not necessarily means mark less so Markus patient might not have tattoos placed at the time of sim. However, temporary marks can still be placed on the patient during a simulation procedure and treatment. In fact, this is something we did when we were transitioning, we’re putting highlighted marks on the patient. So my definition of mark list is treatment flow where there’s no marks of any kind on the patient’s skin. And then just a follow up question, what if there is a tattoos but there are marks on the immobilization device? Well, to me, it’s perfectly fine to have anything in immunization device for if you want to use it to help you to set up as long as there’s no tattoos or marks of any kind on the patient.

Alexander Pevsner, PhD, DABR (04:18):

So this is our setup in our clinic. We have a TrueBeam with a AlignRT, and we purchased our TrueBeam in 2015, was installed with our AlignRT in 2016, and at the time was version five and November 2021, we upgraded to version six and we started markerless in 2022. So if you notice, it was a quite of, quite a long period of time between actually first installing in and going markerless almost six years. But then from installing version six it was only a few months. So, which leads me to next thing, prerequisite and most important prerequisite to implementing the mark less treatment is that all your members of radiation oncology really want to implement this technique. So what happened when we first got our system, we have a physician, they’re sort of older generation, so we have one physician.

Alexander Pevsner, PhD, DABR (05:18):

She was doing only prone breasts, and she view Vision RT as a technique that only can be utilized for supine BIDH. So she felt there is really not much for me with that technique. As physician we had, he was doing ss but he was a, a strong proponent of frameless ss. So he didn’t feel like there is too much use in using the you know, doing a frame list where that’s where Vision RT would come in. So for a really long time, we underutilized our, our system until we got became a part of a larger system and two new physicians had joined the practice. There were two young physician had a previous experience using SGRT from other institutions. So they were really, really eager to start the program and utilize the vision rt to, to a full extent so that once we have these two physicians join, we’ll really have a very good start.

Alexander Pevsner, PhD, DABR (06:23):

So a second prerequisite is obviously equipment. So, assuming they already have Vision RT, but before you go on implementing markerless, perhaps there are a few things you want to take a look at. First, check if you have the latest software and hardware from, from the vendor, which is Vision rt. So you don’t want to start the program just to find out a few months later that, you know, there is new hardware coming or new software coming. So it’s perhaps it’s good to sync your mark list with the new upgrades. And this is what we actually did at the time we had version five. We are aware that Vision RT was upgrading to version six. So we actually waited for new version before we proceeded to implement our mark list flow. Also, check if there are additional offerings from a vendor.

Alexander Pevsner, PhD, DABR (07:20):

I think pretty much, I think all of you’re aware that Vision RT offers the advanced RT package with Postural alignment 3D and ROI tools. We actually have all the tools, and we purchase all the tools. We have a subscription. Another thing you want to check is also your LINAC compatibility with Vision RT. So, because you always, you know, connect visionary t to a Linux, so you want to check with your variant or, you know, elect engineer if there is a new versions of software that they you know, available. So just check that you have the latest hardware software for both your Visionary T system and your Linux system. Now you do have to have experience and a trained staff before you’re switching to a markerless flow. I think your staff, your therapist, your physicist should be very comfortable with the system before you start moving on, to the markerless treatment.

Alexander Pevsner, PhD, DABR (08:23):

Another one, prerequisite your mobilization and your SIM procedure. I think this is a really probably key to successfully implementing markerless workflow. So as far as the mobilization, make sure that you know, everything is functional, everything is working. If it’s, if something, you know, contact to vendor, fix it. Or perhaps you are looking to get some new mobilization devices. Perhaps it’s a good idea to get these things first before you go on implementing new mark list workflow. Also, review a SIM procedure. Make sure it’s not an old SIM procedure and it’s current SIM procedure. And all your therapist and your staff adheres to them a new SIM procedure.

Alexander Pevsner, PhD, DABR (09:10):

So this was our implementation plan. So all of us starting with a conventional tattoo sim. So next step was to use tattoos, but implementing vision RT with every single treatments that we were doing. And the next step would’ve been just go mark less. But we had a very short, intermediate step. So what we had a mark less sims, but we were putting marks like a high with a highlighters on the patients. And what, so basically what therapists were doing, they were putting marks and covering what is called point guard, which is, which is pretty much like a transparent band aid. So if a patient would come to a treatment, they’ll still that, that still they have marks. So on the first day, they would align the patient, get the couch, and then they will remove marks. So when they were comfortable, and actually this step was only very temporary, it was like maybe for a few weeks. So then we were very comfortable and we were ready to move on the doing mark list workflows.

Alexander Pevsner, PhD, DABR (10:18):

And actually, before we completely switched, we did a, a very quick end-to-end test. And I demonstrate what we did with a breast setup. And end-to-end test is really good to assess your molo sim setup procedure, your documentation immobilization, and also establish some sort of action levels and tolerance. And for this end-to-end test, we just used the Mannequin Phantom. So what we did, we just assume, the phantom. We went through a treatment planning system and we’re done, we took our phantom to Alin. So we follow our immobilisation procedure. We put our phantom, we put our breast board, we put our phantom, and we turn them the vision rt. And we recorded the deltas. So we just turn around and see how far our deltas from the isocenter. And we repeated this last step like several times.

Alexander Pevsner, PhD, DABR (11:19):

So we basically took the breast board we put the couch in a random position, repeated like several times, and it’s only took us maybe like an hour. And within sort of lunchtime, we were able to repeat this about five times. And we found that our worst-case scenario was 1.5 cm. So we use it as sort of a, in our SOP as the action level. If we put a patient on a table and our deviation is larger than 1.5 cm, then we have to review our setup procedure. And I think it’s a very important step. Vision RT is a, a very powerful tool. And you can even put a patient as far as 10 cm away from the isocenter. It will still detect it. But if you putting a patient 10 cm from the isocenter, there’s something really wrong with your setup, I think you should be putting close to like one, one, you know, one and a half.

Alexander Pevsner, PhD, DABR (12:20):

So we did one and a half, but we don’t see anything more than one in, in our, in our practice. So this is just because sort of a tolerance to make sure to alert or like have a red flag saying that, Hey, you know what, if there’s more than that, stop it. Take a look review. Maybe indexing is not, or maybe board is not in the, in the right position. So it was a very good test, very easy to do, and we got really a lot out of it. So once we start our markerless flow we said, well, we started, but let’s evaluate our, our process. So here’s what we did. So to evaluate the accuracy, we assessed by examining radiation oncologist approved table shifts after patient was positioned with a markerless vision RT on the first day of treatment.

Alexander Pevsner, PhD, DABR (13:12):

So what we are doing, we’re having a PA patient is on a table, we are positioning patient with vision rt, then we take our ports and then physician says, well, I need to move a patient. And then at the time we have a, a, a mosaic r and v, a recurring verify system. And we were pre, we were able to get the, the shifts the final shifts. So our therapist, our lead therapist Jonathan he I’m credited him with giving this stable. So we just randomly selected 20 patients. So patients from align mark flow cohort one with align it plus tattoos, and one where we just have a tattoo only workflow. So we just, just randomly selected 20 breast patients. So, and we have like two tables with a summary. So one table, I just recorded like a maximums shifts.

Alexander Pevsner, PhD, DABR (14:12):

And the other table is just a statistical comparison. So I’m just going to go straight to a statistical comparison test. So first we compare Marla versus tattoo plus vision rt. So no significant difference. We’re getting very comparable setup accuracies, but where we compare markerless and conventional, we see a significant difference. So with the mark less four flow, we actually able to get a better accuracy for the setup. So we’re very comfortable that what we’re doing is what we intended to do. So we, we getting very good results and we are very happy with our workflow and there is no need to make any adjustments to what we have.

Alexander Pevsner, PhD, DABR (14:59):

So there were many discussions here about vision rt. What is Vision rt? And a recurrent theme is it’s an efficiency tool. So there was excellent talks showing how efficient it is, how, you know, the time savings. But to me, visionary is not only a time saving tool, it’s a, it’s a really a radiation safety tool. And, and here’s an example. When know we do a three field breast, I noticed that we have cases where SCL is extremely close to the chin. And if you think about a little motion chin, you know, could have patient exposed to it. So I started requesting the, we have therapies doing ROI, doing the chin contour and using as a, as an auxiliary to the main tangents, ROI. So just to make sure that chin position is out of the, you know, what it’s intended to be and it’s not in the way of scl. And you know, we can monitor during that, that during a treatment. So it’s not an efficiency tool. It’s also you can utilize as really as a radiation safety tool.

Alexander Pevsner, PhD, DABR (16:12):

So this is a summary. So we successfully implemented markerless workflow and it requires efficient preparation, planning, and teamwork. We SGRT the mark less workflow is used for every site we’re using for every single patient, for every site. And I would like to stress one more time that SGRT is not only efficiency too, but it’s also radiation safety tool. And we’re constantly looking for new ways to use RGRT for everyday treatments and quality assurance work.