SGRT Forum

At one of our centers have been using VARIAN RPM in CT SIM to coach the patient into an appropriate breath hold level for DIBH. At another center where we recently installed a new linac and VisionRT, we do not have VARIAN RPM at all. I was just informed that GateCT is not useful for determining breath hold level in CT SIM. How do centers determine appropriate breath hold levels for their DIBH patients in CT SIM? I assume one can use the lateral scout image to coach the patient into an appropriate breath hold or one could use skin marks and a ruler, but is there a better way to go about this in the absence of a VARIAN RPM system in CT SIM?

Hi, at our clinic we have been using GateCT to coach DIBH patients, capture breathing curves and measure the DIBH amplitude at our CT for six years. It works fine.

Watching for responses... we'll be in the same situation before too long.

Hi Jose. Hope you're well. GateCT can be used to determine if the patient consistently achieves the same level of breath hold (coaching prior to acquiring the breath hold scan) as well as ensuring the patient maintains the breath hold during the scan acquisition (tracking). It is a slightly different approach/concept to determining an absolute amplitude. A clinical applications specialist will reach out to you shortly to discuss this in further detail.

Hi Jose
We use the lasers in the room and pen marks to coach the patients in the room, then have a camera positioned to look at the pen mark on the left hand side to ensure the patient recreates the same breathold immediately prior to scanning. We use this in combination with AlignRT for DIBH on the linacs, and ensuring that the patient is adequately coached and selected at CT, it works really well. The new version of GateCT (SimRT) has the ability to use the same coaching tool at treatment in the CT room, but we haven't tried this out yet so I can't give you any guidance on how it works. We've managed without it successfully though since 2017, so it can be done easily.

Hi JOse，In our center, we have 2 CT scanners and only one RPM System. We don't start DIBH either. The main reason is we can't assurance the breath level by using Varian RPM System, cause if you use laser and base on the pen marks on the patient's hand side, you can't sure that every deep breath is in one same level, but if you have the real-time video camera to verify the every laser line and see is there two sign are matched, however, we also can't quite confirm immediately is RPM shows the breath curves are correct, cus it only shows a part of our breath process, the lowest point on the breath curves in RPM system is not the actual deep breath reference. So you can prepare for DIBH make sure you have the real-time camera in CT room.

At Auckland Hospital NZ and in my previous experience I have only used the personal BH coaching and pen marks for measure. The camera is angled towards the pen mark and the patient is instructed to breath in/out. It works well for some but not for all there can be inconsistencies.

Thanks everyone for your responses.

Hello,
We are going to install the RGSC on our radiotherapy scanner and we are thinking about the VisionRT solution at the treatment stations.
I would like to know if any of you had this setup and if it worked well?
If so, are there any particularities to know?
Thanks in advance
Have a nice day