Radiosurgery made easy: the role of the Gamma Knife in modern radiotherapy

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Hello, and welcome to the Physics World weekly

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podcast.

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This episode is sponsored

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by Elekta.

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Looking for easy and efficient

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radio surgery?

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Meet Elekta Esprit,

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the latest Lexel gamma knife.

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With less than ten minutes of daily QA

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and no patient specific QA,

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Esprit

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streamlines your workflow,

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allowing you to focus on what matters most,

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your patients.

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Discover the future of efficient radio surgery with

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Elekta

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Esprit.

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Learn more at Elekta.com.

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This episode of the Physics World weekly podcast

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features the medical physicist,

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Alonso Gutierrez,

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in conversation

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with Physics

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World's Tammy Freeman.

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The Lexel Gamma Knife is a high precision

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radiation treatment system,

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but the gamma knife is very different to

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conventional X-ray based radiotherapy

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devices.

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It uses an array of roughly 200 tiny

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radioactive sources to focus gamma rays directly onto

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the target,

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most commonly to destroy brain tumors in one

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fraction using a technique known as radiosurgery.

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I'm speaking today with Alonzo Gutierrez,

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chief physicist at the Miami Cancer Institute,

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about his experience of using the Lexile Gamma

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Knife for radiosurgery

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in a busy radiotherapy department.

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Welcome to the podcast, Alonzo.

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Well, hi. Good morning, good afternoon, depending on

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where in the world you're listening to. So

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it's an absolute pleasure to be here and,

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look forward to,

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to chatting a little bit about the, gamma

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knife,

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dreaming unit.

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Excellent. So first of all, could you briefly

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describe how a gamma knife works and how

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it's different from the more prevalent external beam

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radiotherapy systems?

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Sure. So the, gamma knife,

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radiosurgery unit, is really

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a dedicated platform that is, you know, distinctly

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different compared to,

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you know, linac based radiosurgery delivery approaches. One

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is that it uses different types of sources.

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So linear accelerators

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tend to use a linear accelerating device that

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accelerates electrons and generates photons

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based off of production.

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The gamma knife unit uses cobalt 60,

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has the radio isotope that delivers the gamma

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rays through natural decay. The energy is also

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slightly different. So

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the most linear accelerators tend to use six

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megavoltage,

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photon beam energy, whereas the average decay product

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of cobalt 60 is 1.25

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MeV,

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so it's a slightly lower energy.

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On top of that, in terms of the

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localization,

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for patients,

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both treatment delivery platforms can deliver both

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frame based deliveries where patients are immobilized using

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a

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frame

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that is, you know, placed in via pins

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to the patient's skull

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or with a thermoplastic

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mask that is custom molded to the patient,

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and it serves as sort of a immobilization

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device to prevent the patient's head from moving

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during the course of treatment.

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This could be done on both delivery platforms.

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On top of that, and more more recently

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with the latest platform which is the Gamma

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Knife Esprit,

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you have the addition of onboard imaging

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and typically and historically

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the way that a lot of radiosurgery was

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done was through the frame using lasers

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to align the patients to the isocenter of

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the treatment delivery approach. Similarly with

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Gamma Knife, it was using a frame through

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a coordinate system.

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Now with the addition of image guided, you're

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able to acquire a high resolution

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volumetric

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cone beam CT

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that could be used to localize

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the patient

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and place the patient in the correct position

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before treatment, for each,

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for each lesion or isocenter that's being delivered.

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Okay. So it's the cobalt cobalt 60 sources

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that are emitting the gamma rays that's used

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for the,

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treatment. So you actually have these a 92

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small sources that could be delivering radiation at

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the same time. So,

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when you deliver and you have these radioactive

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sources, you can, have an output of around

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three and a half gray, per minute in

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terms of at the ISO center,

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when you're using the largest columnator size.

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Now

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the difference between that is, as you deliver

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this, the, the radiation, it's been delivered from

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all 360 degrees around the patient head.

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Typically, with linear accelerators, you deliver it

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at specific set angles

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or kind of as

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a kind of rotating dynamic arc in which

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you're able to deliver the radiation as a

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function of time.

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And so these sources stay in place. They're

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calibrated

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at the time that the sort the gamma

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knife unit is loaded.

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And then after that, the dose rate will

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fall off as the system

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as

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a cobalt 60 decays.

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And so that's the key difference, whereas with

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other delivery systems,

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such as a linac based solution, you have

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a linear accelerator that's producing the fixed dose

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rate,

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over time to be able to do the

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actual delivery. In the planning process, which is

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part of, how you would sort of modulate

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the dose from these go out sources,

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you have combinations of different collimator settings as

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well as different sectors. And so there's eight

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sectors that are geometrically spaced around,

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the patient head, and each one has 24

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sources. And by turning on and off these

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sectors, you can modulate the dose and get

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different dose distributions,

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and that's all done as part of the,

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treatment planning system and the, dedicated treatment planning

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software for Gamma

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Knife.

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Okay. And Gamma Knife is

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mostly used for,

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treating brain cancers. So what why is it

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so particularly suited for that cancer type?

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Well, I I I think in in general,

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the system, from his inception was designed, to

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replace the surgeon's knife and the term gamma

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knife and to be able to

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target,

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lesions, that are deep inside the brain are

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very difficult, challenging to get to.

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And with that,

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the design of the system was thought, with

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the understanding that, it would have very high

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accuracy,

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very good precision,

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and would be dedicated to cranial radiations. And

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so

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diseases that we treat are obviously those that

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are particularly with brain tumors, so metastatic brain

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tumors. So here at MCI, we treat about

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eighty five percent of our volume as brain

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tumors. However, there's other types of diseases that

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it's been shown to be very efficacious for.

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So meningiomas,

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vestibular schwannomas,

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some pituitary adenomas,

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and some gliomas, which are very common. On

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top of that, there's other indications,

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that are, not necessarily malignant tumors,

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but, you know, AVM, so any vascular malformations

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and or any functional disorders like trigeminal neuralgia

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or essential tremor, those that are being sort

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of explored,

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using resurgery approaches.

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And Gamma Knife has been a device that's

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been used to, treat, many of these for

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for a number of years and has been

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a proven platform to have,

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good success in treating these diseases.

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Oh, that's interesting. And, it's one of the

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reasons it's particularly suited for the brain that

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you can do this sort of complete

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immobilization

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to make sure that the the patient is

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held completely

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stationary during the treatment.

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Correct. And I I think one of the

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big aspects of that is the accuracy.

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And so many of these lesions that you're

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targeting are very small,

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and especially when you get into the functional

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disorders where your target volumes are two to

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three millimeters.

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And so the resolution is, the resolution and

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accuracy is very important

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in doing so. And, you can accomplish that

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by having frame based immobilization,

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or frameless now with,

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with the

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addition of the

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CBCT

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capabilities and the mass based solution that we

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have there.

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But, historically,

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the frame based solution has shown exceptional accuracy,

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submillimeter accuracy. And I think one of the

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key attributes and one of the reasons why

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we sort of looked,

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to Gamma Knife as our our workhorse with

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radiosurgery delivery is the ability to have, you

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know, sustained and stable accuracy.

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The system inherently is very heavy.

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There are, minimal moving parts. The couch and

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the sectors are principally the ones that move

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the most. And and the idea there is

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because of this, the accuracy is sustained over

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amount of time. So,

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we aren't so concerned with potential parts wearing

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over time.

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Then we've seen that as we've sort of

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published our own results on the stability and

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the accuracy

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of systems, and we are able to sustain,

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submillimetric

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accuracy,

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over a number of years. And this has

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been our case for us since we've been

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treating with it for over eight years.

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Okay. And

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so why is there a a need for

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a dedicated system such as this for the

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brain,

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when linear accelerators can do intracranial and extracranial

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stereotactic radiosurgery?

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No. Very, very fair point and very good

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question, especially now in in modern day era

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where, we see a number of,

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universal delivery systems, such as CRM Linacs,

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that have the capability of delivering radiosurgery. We

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also see other,

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dedicated radiosurgery platforms that are available in the

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market.

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I think part of it comes with, the

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abilities,

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or the capabilities of the delivery system and

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also the volume.

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You know, generally, busier practices such as Miami

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Cancer Institute see a high volume, so we

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typically treat over three hundred fifty patients in

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cases per year. And so for us, having

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a dedicated platform to sustain

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and to be able to support this volume

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is very key.

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At the same time, I think one of

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the big attributes with the GavenLife platform is

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the dedicated and and really efficient workflows.

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And so, for us, given that we treat

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principally,

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brain metastases

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as as our common disease on the platform,

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one of the things that we stay true

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is to ensure that we have very accurate

279
00:10:34,460 --> 00:10:36,914
imaging before we treat, and so all our

280
00:10:36,914 --> 00:10:39,315
MRIs are within forty eight hours of the

281
00:10:39,315 --> 00:10:41,414
treatment of the Gamma Knife platform.

282
00:10:41,954 --> 00:10:43,554
And so in order to do that, we

283
00:10:43,554 --> 00:10:45,154
have to be able to be very efficient,

284
00:10:45,154 --> 00:10:47,414
and Gamma Knife does allow us to,

285
00:10:48,115 --> 00:10:49,714
gives us that that ability to have a

286
00:10:49,714 --> 00:10:52,580
platform where we can quickly take an MR,

287
00:10:52,799 --> 00:10:53,700
create a plan,

288
00:10:54,160 --> 00:10:56,399
and have the plan ready for execution within

289
00:10:56,399 --> 00:10:58,240
forty eight hours. And when you do that

290
00:10:58,240 --> 00:11:00,340
for a large number of patients, it actually

291
00:11:00,639 --> 00:11:03,360
is really a staple to, what we're able

292
00:11:03,360 --> 00:11:03,940
to do.

293
00:11:04,745 --> 00:11:08,105
Couple that with our sort of ability to

294
00:11:08,105 --> 00:11:10,985
ensure that we deliver high quality treatment plans.

295
00:11:10,985 --> 00:11:14,024
And so given its limited mobility, we also

296
00:11:14,024 --> 00:11:16,840
firmly that the quality assurance of the treatment

297
00:11:16,840 --> 00:11:18,700
system itself is very stable,

298
00:11:19,320 --> 00:11:20,379
and very accurate.

299
00:11:20,759 --> 00:11:22,519
So these are some of the the factors

300
00:11:22,519 --> 00:11:24,840
that we sort of, incorporated as we made

301
00:11:24,840 --> 00:11:25,980
the decision to use,

302
00:11:26,519 --> 00:11:29,580
the gamma knife esprits, our our our radiosurgery,

303
00:11:30,519 --> 00:11:32,434
sort of platform of choice.

304
00:11:32,894 --> 00:11:34,014
Yeah. I mean, that was that was my

305
00:11:34,014 --> 00:11:36,735
next question, that you're using the the latest

306
00:11:36,735 --> 00:11:39,214
generation of the Lexel Gamma Knife, which is

307
00:11:39,214 --> 00:11:41,454
the Electro Esprit. How long have you been

308
00:11:41,454 --> 00:11:43,615
using that system, and what what are you

309
00:11:43,615 --> 00:11:45,320
finding its key benefits to

310
00:11:45,779 --> 00:11:47,539
be? Sure. So when we first launched the

311
00:11:47,539 --> 00:11:48,759
center in 2017,

312
00:11:49,139 --> 00:11:51,000
we did a launch with the

313
00:11:51,460 --> 00:11:52,919
Gamma Knife Icon platform.

314
00:11:53,539 --> 00:11:56,340
And at the time, we, launched and and

315
00:11:56,340 --> 00:11:58,500
and really found a nice balance between frame

316
00:11:58,500 --> 00:12:00,434
and frameless cases. So it was sort of

317
00:12:00,514 --> 00:12:02,355
the first time that we'd seen that,

318
00:12:03,075 --> 00:12:04,934
frameless treatments could be performed,

319
00:12:05,634 --> 00:12:07,254
on the Gamma Knife unit.

320
00:12:07,715 --> 00:12:08,534
Since then,

321
00:12:08,914 --> 00:12:10,375
obviously, there's been the

322
00:12:10,835 --> 00:12:12,215
introduction to the Esprit.

323
00:12:12,835 --> 00:12:15,554
And so, once the opportunity presented itself to

324
00:12:15,554 --> 00:12:16,054
upgrade,

325
00:12:16,509 --> 00:12:18,350
we ended up looking at an upgrade for

326
00:12:18,350 --> 00:12:20,269
that system. And what we found so far

327
00:12:20,269 --> 00:12:22,990
is, exactly, what we've seen in the past

328
00:12:22,990 --> 00:12:24,769
is very accurate and consistent,

329
00:12:25,629 --> 00:12:28,529
quality insurance and quality performance of the platform.

330
00:12:29,284 --> 00:12:31,204
There are some changes to the system to

331
00:12:31,204 --> 00:12:33,865
get a refresh. The treatment couch

332
00:12:34,804 --> 00:12:35,625
is updated.

333
00:12:36,164 --> 00:12:38,404
We also have seen that there are some

334
00:12:38,404 --> 00:12:40,745
cover changes with the inclusion of a new

335
00:12:41,170 --> 00:12:43,410
monitor that's now mounted on the treatment unit,

336
00:12:43,410 --> 00:12:44,230
which facilitates

337
00:12:44,769 --> 00:12:46,610
information for the therapists that are signing up

338
00:12:46,610 --> 00:12:47,269
the patients.

339
00:12:47,730 --> 00:12:49,170
I think one of the biggest things have

340
00:12:49,170 --> 00:12:51,190
been the improvements in the

341
00:12:51,649 --> 00:12:54,129
Vantage frame, so changing from the g frame

342
00:12:54,129 --> 00:12:55,334
to the Vantage

343
00:12:55,634 --> 00:12:57,414
frame for stereotactic localization,

344
00:12:58,115 --> 00:13:00,355
as well as the introduction to improvements at

345
00:13:00,355 --> 00:13:02,455
the treatment planning system, most notably,

346
00:13:03,075 --> 00:13:03,975
with lightning.

347
00:13:04,914 --> 00:13:05,394
And,

348
00:13:05,955 --> 00:13:09,154
from a workflow ease, the integrated console has

349
00:13:09,154 --> 00:13:10,294
been something that

350
00:13:10,730 --> 00:13:14,330
our therapists have, have commented on, being that

351
00:13:14,330 --> 00:13:16,809
it's much easier with, you know, single monitor

352
00:13:16,809 --> 00:13:18,809
and the keypad is much easier to use

353
00:13:18,809 --> 00:13:20,190
and more intuitive to use,

354
00:13:20,570 --> 00:13:22,509
compared to its predecessor. So,

355
00:13:22,970 --> 00:13:24,190
you know, for these reasons,

356
00:13:24,490 --> 00:13:26,595
it seems like, you know, our our team

357
00:13:26,595 --> 00:13:28,154
has been very happy with the,

358
00:13:28,674 --> 00:13:30,754
with the upgrade, and and it really has

359
00:13:30,754 --> 00:13:32,914
helped us improve in a number of aspects

360
00:13:32,914 --> 00:13:34,695
in terms of, our overall treatments.

361
00:13:35,235 --> 00:13:37,315
And what what's the Vantage frame that you

362
00:13:37,315 --> 00:13:37,815
mentioned?

363
00:13:38,730 --> 00:13:41,370
So, you know, over the years, there's, in

364
00:13:41,370 --> 00:13:42,990
terms of the frame based treatments,

365
00:13:43,370 --> 00:13:45,529
there's been, sort of the the g frame,

366
00:13:45,529 --> 00:13:46,350
which has been,

367
00:13:46,809 --> 00:13:47,929
the tried and true,

368
00:13:48,649 --> 00:13:51,485
stereotactic frame used for positioning. And,

369
00:13:52,345 --> 00:13:54,504
Elekta has now moved towards using the Vantage

370
00:13:54,504 --> 00:13:56,845
frame, which is a more patient friendly focus,

371
00:13:57,464 --> 00:13:59,865
Vantage frame. And, and so it's actually or

372
00:13:59,865 --> 00:14:03,065
stereotactic frame. And so, it's one that allows

373
00:14:03,065 --> 00:14:05,600
for, you know, openness in front for the

374
00:14:05,600 --> 00:14:07,059
patient. It's a lighter frame,

375
00:14:07,680 --> 00:14:10,320
and it's sort of the new platform moving

376
00:14:10,320 --> 00:14:12,240
forward for Electa to be able to use

377
00:14:12,240 --> 00:14:13,540
for stereotactic localization

378
00:14:14,160 --> 00:14:16,960
when when when when using a frame based

379
00:14:16,960 --> 00:14:17,460
approach.

380
00:14:18,034 --> 00:14:19,735
It's also made of a lighter material,

381
00:14:20,115 --> 00:14:21,095
and it's less,

382
00:14:21,634 --> 00:14:23,975
you know, less prone to artifacts

383
00:14:24,595 --> 00:14:27,315
when doing CT scans. And so overall, the

384
00:14:27,315 --> 00:14:29,954
the the frame is, has been, useful in

385
00:14:29,954 --> 00:14:30,629
terms of,

386
00:14:31,110 --> 00:14:33,910
you know, patient satisfaction and also for, a

387
00:14:33,910 --> 00:14:36,330
number of, you know, treatment planning considerations,

388
00:14:37,269 --> 00:14:39,370
in in the sense of reducing artifacts.

389
00:14:41,429 --> 00:14:43,669
Okay. So, how does the treatment planning for

390
00:14:43,669 --> 00:14:46,024
gamma knife, how does that differ from other

391
00:14:46,024 --> 00:14:47,245
radiotherapy devices?

392
00:14:48,745 --> 00:14:50,424
Well, given that it's a sort of a

393
00:14:50,424 --> 00:14:51,884
a a unique, delivery,

394
00:14:52,424 --> 00:14:52,924
system,

395
00:14:54,105 --> 00:14:54,605
the

396
00:14:56,024 --> 00:14:59,245
gamma knife has its own, Lexile, gamma plan

397
00:14:59,490 --> 00:15:02,289
system. So, the idea there, the LGP as

398
00:15:02,289 --> 00:15:02,950
it's referred

399
00:15:03,330 --> 00:15:05,009
to, is a dedicated trim and planning system

400
00:15:05,009 --> 00:15:06,210
that allows you to do,

401
00:15:06,610 --> 00:15:07,110
essentially,

402
00:15:08,129 --> 00:15:08,950
forward planning,

403
00:15:09,330 --> 00:15:10,769
I e, where you're able to sort of

404
00:15:10,769 --> 00:15:12,375
place ISO centers at shots.

405
00:15:12,934 --> 00:15:15,575
And the principle in which, you know, the

406
00:15:15,575 --> 00:15:16,075
gamma

407
00:15:16,615 --> 00:15:18,154
knife system works is that

408
00:15:18,534 --> 00:15:21,335
once you have a lesion identified, you place

409
00:15:21,335 --> 00:15:22,235
shots or

410
00:15:22,695 --> 00:15:24,875
and you and you and you spheres back

411
00:15:25,095 --> 00:15:27,240
these targets or the contours to be able

412
00:15:27,240 --> 00:15:29,000
to place a number of shots on top

413
00:15:29,000 --> 00:15:30,540
of one another and

414
00:15:31,480 --> 00:15:33,240
the convolution or the sum of all these

415
00:15:33,240 --> 00:15:35,480
shots creates a dose distribution in which you're

416
00:15:35,480 --> 00:15:35,980
targeting

417
00:15:36,759 --> 00:15:37,899
that particular lesion.

418
00:15:38,360 --> 00:15:40,460
And so this historically has been done

419
00:15:41,335 --> 00:15:43,254
forward plan. And so part of the art

420
00:15:43,254 --> 00:15:44,554
of of treatment planning

421
00:15:44,934 --> 00:15:47,014
was to be able to know how to

422
00:15:47,014 --> 00:15:49,754
place these these isosenders and shots.

423
00:15:50,695 --> 00:15:53,414
And over time, there's sort of been improvements

424
00:15:53,414 --> 00:15:55,669
in the way of doing so, mostly in

425
00:15:55,669 --> 00:15:58,070
having inverse planning approaches. And so there's been

426
00:15:58,070 --> 00:15:59,590
a couple of generations of,

427
00:15:59,910 --> 00:16:01,690
inverse planning, most notably,

428
00:16:02,149 --> 00:16:02,389
the,

429
00:16:03,110 --> 00:16:05,669
fast inverse planning or or or lightning as

430
00:16:05,669 --> 00:16:07,904
the trademark is has been a solution that

431
00:16:07,904 --> 00:16:08,545
has been,

432
00:16:09,024 --> 00:16:10,725
has done has done very well.

433
00:16:11,345 --> 00:16:13,585
We've, we were one of the first adopters

434
00:16:13,585 --> 00:16:15,424
of the lightning treatment planning system, and the

435
00:16:15,424 --> 00:16:17,424
idea here is that we're able to get

436
00:16:17,424 --> 00:16:20,485
very high quality plans very, very fast.

437
00:16:21,879 --> 00:16:25,080
And so the inverse planning approach there gave

438
00:16:25,080 --> 00:16:25,740
good quality,

439
00:16:26,040 --> 00:16:26,519
plans,

440
00:16:26,920 --> 00:16:28,139
for many of our cases.

441
00:16:28,759 --> 00:16:30,600
We have published on this or our our

442
00:16:30,600 --> 00:16:33,100
our group has done extensive work with Lightning,

443
00:16:33,634 --> 00:16:35,875
and we've shown that we can, in essence,

444
00:16:35,875 --> 00:16:38,835
improve the quality of our clinical plans with

445
00:16:38,835 --> 00:16:39,335
Lightning.

446
00:16:39,875 --> 00:16:41,955
We could do it substantially faster. I think

447
00:16:41,955 --> 00:16:44,754
over, the cases that we evaluated, plans were

448
00:16:44,754 --> 00:16:46,995
completed in less than five minutes, especially for

449
00:16:46,995 --> 00:16:47,815
multi targets.

450
00:16:49,050 --> 00:16:51,070
At the same time, we also showed that,

451
00:16:51,610 --> 00:16:53,070
there's sort of a

452
00:16:54,009 --> 00:16:56,090
emphasis on quality of these plans. And so

453
00:16:56,090 --> 00:16:56,830
these plans,

454
00:16:57,529 --> 00:16:59,850
required, you know, minor tweaking after the fact.

455
00:16:59,850 --> 00:17:00,490
And and,

456
00:17:00,889 --> 00:17:02,750
as solutions came from Lightning,

457
00:17:03,404 --> 00:17:05,424
they were very, you know, high quality.

458
00:17:06,125 --> 00:17:08,045
At the same time, we also noted that,

459
00:17:08,605 --> 00:17:09,744
it was somewhat

460
00:17:10,365 --> 00:17:12,204
not dependent on the planner and so we

461
00:17:12,204 --> 00:17:13,664
did a study where we evaluated,

462
00:17:14,204 --> 00:17:16,204
you know, a novice, an intermediate, and an

463
00:17:16,204 --> 00:17:17,099
expert planner,

464
00:17:17,900 --> 00:17:19,839
And if they were able to plan manually

465
00:17:19,900 --> 00:17:20,960
compared to lightning,

466
00:17:21,259 --> 00:17:22,640
the lightning plans were

467
00:17:23,019 --> 00:17:23,519
essentially

468
00:17:24,059 --> 00:17:25,980
eliminated the need of experience. And so we

469
00:17:25,980 --> 00:17:28,779
were able to generate very fast high quality

470
00:17:28,779 --> 00:17:29,279
plans

471
00:17:29,615 --> 00:17:31,615
with Lightning. So that's a testament to a

472
00:17:31,615 --> 00:17:33,215
lot of the work that's been done with

473
00:17:33,215 --> 00:17:35,375
Electa to be able to show that, the

474
00:17:35,375 --> 00:17:37,795
improvements in in in in quality are there.

475
00:17:38,335 --> 00:17:40,494
And we feel confident that that helps standardize

476
00:17:40,494 --> 00:17:41,154
us irrespective

477
00:17:41,640 --> 00:17:43,079
of the number or the different types of

478
00:17:43,079 --> 00:17:44,839
physicists that are planning that we can obtain

479
00:17:44,839 --> 00:17:46,539
very high quality plans for our patients.

480
00:17:47,320 --> 00:17:49,799
Okay. And then so you're mentioning these shots.

481
00:17:49,799 --> 00:17:51,900
I presume these are the shots of radiation

482
00:17:52,039 --> 00:17:53,420
from the cobalt sources.

483
00:17:53,924 --> 00:17:54,424
So

484
00:17:55,924 --> 00:17:57,945
how does, how is this radiation

485
00:17:58,325 --> 00:18:00,644
steered onto the target to get it really

486
00:18:00,644 --> 00:18:01,144
conformal?

487
00:18:02,565 --> 00:18:03,125
So the,

488
00:18:03,924 --> 00:18:05,365
the way that it works is the,

489
00:18:05,924 --> 00:18:08,644
sources, the 92 sources are focused to an

490
00:18:08,644 --> 00:18:09,144
isocenter,

491
00:18:09,619 --> 00:18:12,019
and they're collimated. And the way that the,

492
00:18:12,420 --> 00:18:12,920
sources

493
00:18:13,299 --> 00:18:14,759
are you know, the

494
00:18:15,700 --> 00:18:17,240
shots are placed is,

495
00:18:17,539 --> 00:18:19,460
you can have a combination of all these

496
00:18:19,460 --> 00:18:21,700
eight sectors being open with the same collimator,

497
00:18:21,700 --> 00:18:23,805
and so that would produce a shot of,

498
00:18:23,884 --> 00:18:25,664
for instance, eight millimeters,

499
00:18:26,525 --> 00:18:28,684
if you have that. So that would be

500
00:18:28,684 --> 00:18:30,465
one shot. You can, in essence,

501
00:18:31,325 --> 00:18:33,244
block some of these sectors so you can

502
00:18:33,244 --> 00:18:34,845
have, you know, one or two or a

503
00:18:34,845 --> 00:18:36,839
couple of these sectors be off, and the

504
00:18:36,839 --> 00:18:39,400
remainders could be turned on, to eight millimeters,

505
00:18:39,400 --> 00:18:41,079
and then you would have a different shape

506
00:18:41,079 --> 00:18:42,140
of a dose distribution.

507
00:18:42,519 --> 00:18:45,819
And similarly, you can have combinations of four,

508
00:18:46,279 --> 00:18:47,339
eight, and sixteen

509
00:18:47,640 --> 00:18:48,859
in any given pattern

510
00:18:49,294 --> 00:18:50,434
to be able to

511
00:18:50,734 --> 00:18:52,194
create different dose distributions.

512
00:18:53,134 --> 00:18:55,315
There are some benefits, of course, to using

513
00:18:55,375 --> 00:18:57,454
larger shots, so you tend to reduce some

514
00:18:57,454 --> 00:18:59,454
of the treatment time. So there are improvements

515
00:18:59,454 --> 00:19:01,454
in efficiency as you use larger shots. And

516
00:19:01,454 --> 00:19:03,054
so I think one of the key things

517
00:19:03,054 --> 00:19:04,950
that we found with lightning was

518
00:19:05,429 --> 00:19:06,089
the combinations

519
00:19:06,470 --> 00:19:08,169
of these shots in sectors,

520
00:19:08,869 --> 00:19:11,269
change, when you have an inverse planning solution

521
00:19:11,269 --> 00:19:14,309
versus a forward plan or manual plan. As

522
00:19:14,309 --> 00:19:16,710
you can imagine, computers do a great job

523
00:19:16,710 --> 00:19:19,065
and do it much faster, in terms of

524
00:19:19,065 --> 00:19:21,065
determining solutions. And so what we've noticed is

525
00:19:21,065 --> 00:19:23,544
that, with Lightning, we're able to get, you

526
00:19:23,544 --> 00:19:25,224
know, you know, as a equivalent or better

527
00:19:25,224 --> 00:19:27,144
quality plans in a much faster time than

528
00:19:27,144 --> 00:19:29,384
someone that would do it manually because we

529
00:19:29,384 --> 00:19:31,544
end up seeing the use of, you know,

530
00:19:31,544 --> 00:19:32,285
you know, unconventional

531
00:19:32,950 --> 00:19:34,710
sort of distributions where we tend to see

532
00:19:34,710 --> 00:19:37,109
bigger shots more commonly used than smaller shots,

533
00:19:37,109 --> 00:19:39,269
which allows us to reduce the overall treatment

534
00:19:39,269 --> 00:19:40,090
time. So,

535
00:19:40,549 --> 00:19:42,390
with that said, you know, the manipulation of

536
00:19:42,390 --> 00:19:44,490
being able to generate the optimal combination,

537
00:19:45,794 --> 00:19:48,034
obviously improves with lightning as opposed to an

538
00:19:48,034 --> 00:19:50,434
individual doing a manual plan. And and you

539
00:19:50,434 --> 00:19:52,434
see this more case when the lesions get

540
00:19:52,434 --> 00:19:54,694
bigger and bigger. For very small lesions,

541
00:19:54,994 --> 00:19:56,515
you don't, you know, tend to see a

542
00:19:56,515 --> 00:19:57,335
lot of modulation

543
00:19:57,730 --> 00:19:59,909
in terms of selection of these different shots,

544
00:20:00,210 --> 00:20:02,450
but as they become more complicated, you do.

545
00:20:02,450 --> 00:20:03,809
And then that's really where you see the

546
00:20:03,809 --> 00:20:06,049
testament of, of using the system like the,

547
00:20:06,289 --> 00:20:07,509
like lightning for that.

548
00:20:08,130 --> 00:20:10,865
Okay. So, basically, you've got this array of

549
00:20:10,865 --> 00:20:13,024
cobalt sources around the skull, and then you

550
00:20:13,024 --> 00:20:13,845
use the collimators

551
00:20:14,704 --> 00:20:17,825
to shape the beams coming from these different

552
00:20:17,825 --> 00:20:18,325
sources,

553
00:20:19,664 --> 00:20:21,585
based on the treatment planning to to sort

554
00:20:21,585 --> 00:20:24,085
of really target as conformally as possible.

555
00:20:24,640 --> 00:20:26,319
Correct. And and and I think the the

556
00:20:26,319 --> 00:20:28,579
two, you know, key parameters typically

557
00:20:28,880 --> 00:20:31,119
are, you know, conformity at the prescription dose

558
00:20:31,119 --> 00:20:32,980
and and the fall off. And so,

559
00:20:33,279 --> 00:20:35,200
you wanna ensure that you're covering the target.

560
00:20:35,200 --> 00:20:37,519
So target coverage is key and principle, to

561
00:20:37,519 --> 00:20:38,960
make sure that you're not missing part of

562
00:20:38,960 --> 00:20:39,615
the tumor.

563
00:20:40,095 --> 00:20:42,494
Typically, you have very little margin of error

564
00:20:42,494 --> 00:20:44,335
there, so you have to ensure that the

565
00:20:44,335 --> 00:20:46,494
accuracy and the delivery and your and and

566
00:20:46,494 --> 00:20:48,674
the coverage of the lesion is is paramount.

567
00:20:49,214 --> 00:20:51,615
Then, you look at how conformal is your

568
00:20:51,615 --> 00:20:52,115
dose,

569
00:20:52,494 --> 00:20:54,335
sorry, is your is your shape of your

570
00:20:54,335 --> 00:20:56,019
dose cloud to your

571
00:20:56,319 --> 00:20:58,259
target, and that's at the prescription level.

572
00:20:58,880 --> 00:20:59,539
And then,

573
00:21:00,399 --> 00:21:02,799
typically, half of the prescription level, you make

574
00:21:02,799 --> 00:21:05,200
sure that that's also very tight, and that

575
00:21:05,200 --> 00:21:06,799
really just is an indicator of the measure

576
00:21:06,799 --> 00:21:08,399
of the fall off of the radiation because

577
00:21:08,399 --> 00:21:10,704
you wanna make sure that you also don't

578
00:21:10,704 --> 00:21:12,164
spread a lot of lower doses

579
00:21:12,944 --> 00:21:14,964
without really controlling it. And so

580
00:21:15,345 --> 00:21:17,105
that typically is measured by sort of a

581
00:21:17,105 --> 00:21:19,365
gradient index and then you have a conformity

582
00:21:19,505 --> 00:21:22,464
index that that quantifies both of these parameters.

583
00:21:22,464 --> 00:21:23,125
And so

584
00:21:23,509 --> 00:21:25,829
that's something that we actively monitor, in our

585
00:21:25,909 --> 00:21:27,589
in in in all our treatment plans, and

586
00:21:27,589 --> 00:21:30,409
we make sure that, we have very tight

587
00:21:30,629 --> 00:21:31,129
prescription

588
00:21:31,669 --> 00:21:33,750
and dose fall offs for all our treatment

589
00:21:33,750 --> 00:21:34,250
plans.

590
00:21:34,789 --> 00:21:36,710
Right. And and the tight dose fall off

591
00:21:36,710 --> 00:21:39,014
is to stop, the radiation getting to the

592
00:21:39,014 --> 00:21:40,394
normal tissue in the brain?

593
00:21:40,855 --> 00:21:42,454
Correct. And and and I think in part

594
00:21:42,454 --> 00:21:43,835
of the reason is is typically,

595
00:21:44,375 --> 00:21:45,974
when you have these lesions that are kind

596
00:21:45,974 --> 00:21:47,335
of in in the brain,

597
00:21:47,974 --> 00:21:48,855
the only other,

598
00:21:49,255 --> 00:21:51,500
normal tissue is the brain that's surrounding

599
00:21:51,880 --> 00:21:53,500
it. When it's normally

600
00:21:53,960 --> 00:21:56,200
adjacent to the brain stem, optic eyes and

601
00:21:56,200 --> 00:21:57,099
optic nerve,

602
00:21:57,559 --> 00:21:59,579
you do have constraints there and you and

603
00:21:59,640 --> 00:22:01,160
and you do plan to ensure that you

604
00:22:01,160 --> 00:22:02,700
meet those radiation dose constraints.

605
00:22:03,045 --> 00:22:04,404
But when you don't have something,

606
00:22:04,805 --> 00:22:06,884
adjacent to it, in reality, you just have

607
00:22:06,884 --> 00:22:08,085
to make sure that you have the fastest

608
00:22:08,085 --> 00:22:10,325
fall off. You know, typically, the concern, of

609
00:22:10,325 --> 00:22:12,265
course, with normal brain is is brain necrosis,

610
00:22:12,805 --> 00:22:15,445
and we know there's correlations between increased volumes

611
00:22:15,445 --> 00:22:17,990
of, you know, various dose levels, leads to

612
00:22:17,990 --> 00:22:19,369
higher rates of necrosis.

613
00:22:19,909 --> 00:22:21,509
And so you really wanna ensure that you

614
00:22:21,509 --> 00:22:23,750
can, minimize the amount of normal brain tissue

615
00:22:23,750 --> 00:22:24,650
that's being rated.

616
00:22:25,990 --> 00:22:28,150
Okay. And then in terms of ease of

617
00:22:28,150 --> 00:22:30,644
use, how does the Gamma Knife compare to

618
00:22:30,644 --> 00:22:31,464
other technologies?

619
00:22:33,125 --> 00:22:34,804
You know, I I I think, you know,

620
00:22:34,804 --> 00:22:37,125
one of the key aspects in terms of

621
00:22:37,125 --> 00:22:40,424
of of any type of, dedicated platform is,

622
00:22:41,460 --> 00:22:43,299
they tend to approach it with an integrated

623
00:22:43,299 --> 00:22:44,680
solution. And so,

624
00:22:45,059 --> 00:22:46,579
what you end up seeing is that you

625
00:22:46,579 --> 00:22:47,480
have a dedicated,

626
00:22:47,779 --> 00:22:50,519
you know, software package that follows a workflow

627
00:22:50,579 --> 00:22:52,200
of how you wanna do the deliveries.

628
00:22:52,945 --> 00:22:55,345
You have an integrated treatment planning system that

629
00:22:55,345 --> 00:22:57,045
supports the way in which you deliver,

630
00:22:57,505 --> 00:22:59,845
and then you have, you know, QA devices

631
00:23:00,065 --> 00:23:01,845
and or this delivery system,

632
00:23:02,305 --> 00:23:04,785
that's able to facilitate its overall delivery. So

633
00:23:04,785 --> 00:23:06,144
you don't have much of a mix and

634
00:23:06,144 --> 00:23:08,420
match, and so the system is sort of

635
00:23:08,420 --> 00:23:10,500
built for a purpose. And I think that's

636
00:23:10,500 --> 00:23:12,019
one of the key things in terms of

637
00:23:12,019 --> 00:23:13,240
the overall workflow

638
00:23:13,539 --> 00:23:15,220
of of the system is that it allows

639
00:23:15,220 --> 00:23:16,039
for it to be,

640
00:23:16,900 --> 00:23:18,039
you know, very efficient.

641
00:23:18,580 --> 00:23:20,180
And I think for us, that's key, you

642
00:23:20,180 --> 00:23:21,884
know, given the the the idea that we

643
00:23:21,884 --> 00:23:23,644
talked about is ensuring that we can, you

644
00:23:23,644 --> 00:23:24,705
know, treat patients,

645
00:23:25,085 --> 00:23:25,904
rather quickly,

646
00:23:26,445 --> 00:23:28,225
once we know that there's a diagnosis.

647
00:23:28,924 --> 00:23:30,445
On top of that, I I would say,

648
00:23:30,445 --> 00:23:32,125
you know, in terms of the ease of

649
00:23:32,125 --> 00:23:34,785
use on the physics side of things, there's,

650
00:23:35,069 --> 00:23:36,529
although there's a QA program,

651
00:23:37,549 --> 00:23:40,349
associated with it, it is very simple to

652
00:23:40,349 --> 00:23:42,049
use. I mean, I think,

653
00:23:42,349 --> 00:23:44,509
given its longevity and years of history, the

654
00:23:44,509 --> 00:23:46,990
overall performance is well characterized for a Gamma

655
00:23:46,990 --> 00:23:47,809
Knife unit.

656
00:23:48,825 --> 00:23:50,204
And, Electa was

657
00:23:51,304 --> 00:23:52,125
does provide

658
00:23:52,744 --> 00:23:55,304
a very efficient QA tools to be able

659
00:23:55,304 --> 00:23:57,244
to quickly test key parameters

660
00:23:58,025 --> 00:24:00,684
such as, you know, cone beam CTS eccentricity,

661
00:24:01,399 --> 00:24:02,779
radiation focus point,

662
00:24:03,159 --> 00:24:04,940
in congruence with imaging isocenter.

663
00:24:05,960 --> 00:24:08,519
And in reality, as you mentioned, we we

664
00:24:08,519 --> 00:24:11,079
don't expect to see fluctuations in dose rate

665
00:24:11,079 --> 00:24:13,240
because it is a, you know, a radioactive

666
00:24:13,240 --> 00:24:14,654
source that decays with time.

667
00:24:15,615 --> 00:24:18,095
At the same time, as I mentioned before,

668
00:24:18,255 --> 00:24:20,095
given sort of the the minimal amount of

669
00:24:20,095 --> 00:24:20,914
moving parts,

670
00:24:21,775 --> 00:24:23,855
you don't expect there to be significant wear

671
00:24:23,855 --> 00:24:26,015
with a lot of these these components. And

672
00:24:26,015 --> 00:24:26,515
so,

673
00:24:26,974 --> 00:24:29,700
for us, as we've shown, it's been very

674
00:24:29,700 --> 00:24:32,180
stable. Although we have a very robust quality

675
00:24:32,180 --> 00:24:34,740
assurance program with it, it is very efficient

676
00:24:34,740 --> 00:24:36,340
in terms of the metrics that we measure,

677
00:24:36,500 --> 00:24:37,700
to be able to make sure that the

678
00:24:37,700 --> 00:24:39,400
the system is consistent over time.

679
00:24:40,235 --> 00:24:42,634
And why is it so important that, the

680
00:24:42,634 --> 00:24:43,134
radiosurgery

681
00:24:43,674 --> 00:24:46,414
is both easy to perform and efficient?

682
00:24:47,595 --> 00:24:49,035
No. I I I think, you know, part

683
00:24:49,035 --> 00:24:50,634
of it is time. You know, every everyone's

684
00:24:50,634 --> 00:24:52,015
time is, is important.

685
00:24:52,399 --> 00:24:53,039
And so,

686
00:24:53,359 --> 00:24:56,399
in an ever evolving platform within radiotherapy where,

687
00:24:56,559 --> 00:24:58,640
I would say on the physics side physicist

688
00:24:58,640 --> 00:25:01,279
side of things, procedures are becoming more complicated

689
00:25:01,279 --> 00:25:02,019
and more involved.

690
00:25:02,480 --> 00:25:04,559
Obviously, anytime that you can make things more

691
00:25:04,559 --> 00:25:06,579
efficient, and maintain quality,

692
00:25:07,365 --> 00:25:09,525
I think no one would ever be be

693
00:25:09,525 --> 00:25:12,085
against that. And I think from our end,

694
00:25:12,085 --> 00:25:13,845
that's why it's a very similar case for

695
00:25:13,845 --> 00:25:15,224
for radiosurgery. So,

696
00:25:15,924 --> 00:25:18,265
we wanna make sure that, we can facilitate

697
00:25:18,484 --> 00:25:20,759
the overall efficiency, And I think we see

698
00:25:20,759 --> 00:25:22,600
that at least with the Gamma Knife platform

699
00:25:22,600 --> 00:25:23,420
using lightning,

700
00:25:23,799 --> 00:25:25,480
and so we're able to be very efficient

701
00:25:25,480 --> 00:25:28,119
in acquiring MRs for our patients, in in

702
00:25:28,119 --> 00:25:28,619
time.

703
00:25:28,920 --> 00:25:31,000
We can generate plans very quickly. We can

704
00:25:31,000 --> 00:25:32,140
ensure that the machine,

705
00:25:32,519 --> 00:25:34,539
is QA'd and ready to go with treatment,

706
00:25:34,634 --> 00:25:36,315
and then we could feel confident with the

707
00:25:36,315 --> 00:25:38,494
quality of the treatment that we're delivering,

708
00:25:39,355 --> 00:25:42,234
you know, over time. So, I think for

709
00:25:42,234 --> 00:25:44,075
us, those are some of the factors that

710
00:25:44,075 --> 00:25:45,214
are that are very important.

711
00:25:45,515 --> 00:25:47,630
And at the same time, it does save,

712
00:25:48,089 --> 00:25:49,470
you know, what I would say,

713
00:25:49,849 --> 00:25:51,769
it it ensures that, you know, people are

714
00:25:51,769 --> 00:25:53,529
more focused on the key aspects of the

715
00:25:53,529 --> 00:25:54,829
treatment delivery versus

716
00:25:55,130 --> 00:25:57,390
smaller processes that just take more time.

717
00:25:58,089 --> 00:26:00,484
So so what are the key success factors

718
00:26:00,484 --> 00:26:02,884
when you're integrating a gamma knife into a

719
00:26:02,884 --> 00:26:03,384
radiotherapy

720
00:26:03,924 --> 00:26:04,424
department?

721
00:26:05,524 --> 00:26:06,964
You know, I I would say for for

722
00:26:06,964 --> 00:26:08,884
MCI's experience, I mean, I I think we

723
00:26:08,884 --> 00:26:10,724
have sort of a a a unique approach

724
00:26:10,724 --> 00:26:12,884
to it. I I think one, it comes

725
00:26:12,884 --> 00:26:13,289
with,

726
00:26:13,850 --> 00:26:14,570
in general,

727
00:26:15,289 --> 00:26:17,289
you know, understanding that the machine is a

728
00:26:17,289 --> 00:26:19,210
component of the radiosurgery program and it's not

729
00:26:19,210 --> 00:26:20,509
the radiosurgery program.

730
00:26:20,970 --> 00:26:22,730
And so for us, you know, we took

731
00:26:22,730 --> 00:26:25,529
a very programmatic approach where we ensured a

732
00:26:25,529 --> 00:26:26,830
very multi multidisciplinary

733
00:26:27,289 --> 00:26:30,035
approach with racial oncologists, medical physicists, neurosurgeons,

734
00:26:30,575 --> 00:26:33,134
neuro oncologists to make sure that we developed

735
00:26:33,134 --> 00:26:35,714
a program that, you know, had key pillars

736
00:26:35,775 --> 00:26:38,815
in terms of overall quality, make sure that

737
00:26:38,815 --> 00:26:39,795
the that the

738
00:26:41,000 --> 00:26:42,919
that the machine was being utilized to its

739
00:26:42,919 --> 00:26:45,559
full potential and it was appropriate in terms

740
00:26:45,559 --> 00:26:47,319
of the treatment diseases that we what we

741
00:26:47,319 --> 00:26:47,819
gave,

742
00:26:48,279 --> 00:26:50,859
make sure that, we, you know, ensure that

743
00:26:51,000 --> 00:26:53,159
specific quality metrics for all treatment plans were

744
00:26:53,159 --> 00:26:54,380
insured, you know,

745
00:26:54,765 --> 00:26:56,384
conformity, dose fall off,

746
00:26:56,845 --> 00:26:59,505
and we ensure that we deliver appropriate doses,

747
00:27:00,045 --> 00:27:02,125
in terms of, the different disease types that

748
00:27:02,125 --> 00:27:03,825
we were, you know, going to treat.

749
00:27:04,285 --> 00:27:06,205
At the same time, you know, this is

750
00:27:06,205 --> 00:27:08,000
not sort of a one and done. You

751
00:27:08,000 --> 00:27:08,880
know, we do have,

752
00:27:09,600 --> 00:27:11,059
peer meetings and peer review.

753
00:27:11,440 --> 00:27:13,920
And so, on a weekly basis, we present

754
00:27:13,920 --> 00:27:15,360
all the cases that are, you know, going

755
00:27:15,360 --> 00:27:16,720
to go up to gamma knife for for

756
00:27:16,720 --> 00:27:18,720
gamma knife treatment to make sure that they're

757
00:27:18,720 --> 00:27:21,505
appropriate. We also discuss location, immobilization

758
00:27:22,125 --> 00:27:25,005
type, not just within physicists or radiation oncologist,

759
00:27:25,005 --> 00:27:26,065
but also as a multidisciplinary

760
00:27:26,524 --> 00:27:28,605
care team, to make sure that, you know,

761
00:27:28,605 --> 00:27:30,944
we we're looking at it as a programmatic

762
00:27:31,085 --> 00:27:33,164
approach and not just because we have a

763
00:27:33,164 --> 00:27:35,005
device that can treat radiosurgery. We wanna treat

764
00:27:35,005 --> 00:27:37,380
everything with radiosurgery. So I I think for

765
00:27:37,380 --> 00:27:40,180
us, those have been very important success factors,

766
00:27:40,660 --> 00:27:42,340
in terms of how we've, you know, what

767
00:27:42,340 --> 00:27:43,000
we've done.

768
00:27:43,299 --> 00:27:45,059
It's also important for us to understand how

769
00:27:45,059 --> 00:27:46,820
well we're doing so ensuring that we have

770
00:27:46,820 --> 00:27:47,559
good follow-up,

771
00:27:48,019 --> 00:27:50,660
and and understanding our local control of the

772
00:27:50,660 --> 00:27:52,664
diseases that we treat. And so for us,

773
00:27:52,664 --> 00:27:54,285
we've had a fair number of publications

774
00:27:54,745 --> 00:27:57,465
looking at how accurately we're we're targeting, looking

775
00:27:57,465 --> 00:27:59,705
at how well our our patients are doing.

776
00:27:59,705 --> 00:28:01,065
And so I I think all of those

777
00:28:01,065 --> 00:28:02,985
are just, you know, a handful of of

778
00:28:02,985 --> 00:28:03,644
of key,

779
00:28:03,945 --> 00:28:06,345
you know, factors that, if you really wanna

780
00:28:06,345 --> 00:28:07,404
ensure a very

781
00:28:07,839 --> 00:28:09,859
successful program that you take into account.

782
00:28:10,319 --> 00:28:11,919
And just like with anything, you wanna make

783
00:28:11,919 --> 00:28:13,220
sure you plan for it,

784
00:28:13,759 --> 00:28:15,679
and, you know, you have goals in mind

785
00:28:15,679 --> 00:28:17,279
in terms of what you would wanna accomplish,

786
00:28:17,279 --> 00:28:18,799
and then you just follow-up on that. So,

787
00:28:19,759 --> 00:28:21,424
I I think I would attribute all those

788
00:28:21,424 --> 00:28:23,424
factors to to the success we've had so

789
00:28:23,424 --> 00:28:23,924
far.

790
00:28:24,945 --> 00:28:27,445
Excellent. And then the final question,

791
00:28:27,904 --> 00:28:30,005
both now and looking into the future,

792
00:28:30,384 --> 00:28:32,559
are there any disease types that could be

793
00:28:32,559 --> 00:28:35,119
treated using the gamma knife that perhaps weren't

794
00:28:35,119 --> 00:28:36,180
treatable before?

795
00:28:37,200 --> 00:28:38,799
And I I will say, I mean, as

796
00:28:38,799 --> 00:28:40,720
as as I mentioned earlier in in the,

797
00:28:40,960 --> 00:28:42,559
in the podcast, I I I do think

798
00:28:42,559 --> 00:28:44,400
there's a large number of indications in which

799
00:28:44,400 --> 00:28:46,799
radiosurgery has has has has proven and shown

800
00:28:46,799 --> 00:28:48,804
itself. I think for us, one of the

801
00:28:48,804 --> 00:28:51,304
key things that, we've been able to do

802
00:28:51,524 --> 00:28:52,964
is, you know, there's been sort of a

803
00:28:52,964 --> 00:28:56,264
movement sort of for preoperative surgery. So, obviously,

804
00:28:56,325 --> 00:28:59,304
for cases that have larger, you know, lesions

805
00:29:00,169 --> 00:29:01,929
and are gonna go to resection to be

806
00:29:01,929 --> 00:29:03,769
able to remove them or to be able

807
00:29:03,769 --> 00:29:06,409
to, you know, provide an irradiation or do

808
00:29:06,409 --> 00:29:08,970
a preoperative surgery before the removal, and there's

809
00:29:08,970 --> 00:29:10,890
a lot of advantages. And I think one

810
00:29:10,890 --> 00:29:13,164
of the key aspects of, you know, the

811
00:29:13,164 --> 00:29:14,924
Gamma Knife platform is the ability to do

812
00:29:14,924 --> 00:29:16,865
that. Right? Because it is very efficient,

813
00:29:17,404 --> 00:29:18,785
has a very streamlined workflow,

814
00:29:19,404 --> 00:29:21,404
and you can, you know, turn around and

815
00:29:21,404 --> 00:29:23,345
read a surgery plan in a day.

816
00:29:23,884 --> 00:29:25,724
And, you know, there are other platforms that

817
00:29:25,724 --> 00:29:27,005
you could do it, but when you do

818
00:29:27,005 --> 00:29:29,309
four or five patients, the efficiency is very

819
00:29:29,309 --> 00:29:30,829
important. And so being able to do many

820
00:29:30,829 --> 00:29:32,210
patients very quickly,

821
00:29:33,230 --> 00:29:35,789
has been something that historically has been beneficial

822
00:29:35,789 --> 00:29:37,150
to us. So I would say that if

823
00:29:37,150 --> 00:29:39,390
we look at the diseases that we, likely

824
00:29:39,390 --> 00:29:41,309
wouldn't be treating with other platforms, it would

825
00:29:41,309 --> 00:29:43,815
be these preoperative surgery cases. And, you know,

826
00:29:43,815 --> 00:29:45,815
there are, you know, there is growing data

827
00:29:45,815 --> 00:29:48,534
to to ensure that, you know, that there's

828
00:29:48,534 --> 00:29:50,634
benefits associated with preoperative surgery.

829
00:29:51,174 --> 00:29:53,255
Obviously, one of them being that volumes are

830
00:29:53,255 --> 00:29:55,095
smaller and smaller. You don't you're not worried

831
00:29:55,095 --> 00:29:55,589
about

832
00:29:56,150 --> 00:29:57,049
potential seeding

833
00:29:57,429 --> 00:29:58,329
after the fact

834
00:29:59,349 --> 00:30:01,109
and not knowing what the disease is. And

835
00:30:01,109 --> 00:30:03,509
so for us, this is an area that

836
00:30:03,509 --> 00:30:04,329
we have

837
00:30:04,869 --> 00:30:07,029
to have done here and have a growing

838
00:30:07,029 --> 00:30:09,365
need for it and, have been successful in

839
00:30:09,365 --> 00:30:11,125
terms of being able to accomplish it in

840
00:30:11,125 --> 00:30:12,825
a very efficient time time period.

841
00:30:14,085 --> 00:30:16,964
Excellent. Right. Well, thank you very much. Thanks

842
00:30:16,964 --> 00:30:18,664
for your time speaking to us today.

843
00:30:19,285 --> 00:30:21,750
Oh, my pleasure. And, thank you very much

844
00:30:21,750 --> 00:30:23,910
for for doing this podcast, and and and

845
00:30:23,910 --> 00:30:25,509
great to be able to share this information

846
00:30:25,509 --> 00:30:27,609
to to all the users out there.

847
00:30:34,875 --> 00:30:36,974
That was Alonso Gutierrez

848
00:30:37,355 --> 00:30:40,654
in conversation with Physics World's Tammy Freeman.

849
00:30:41,035 --> 00:30:42,875
I'm afraid that's all the time we have

850
00:30:42,875 --> 00:30:44,095
for this week's podcast.

851
00:30:44,474 --> 00:30:47,775
Thanks to Alonso and Tammy for a fascinating

852
00:30:48,075 --> 00:30:48,575
discussion,

853
00:30:49,259 --> 00:30:50,720
And thanks to our producer,

854
00:30:51,180 --> 00:30:52,160
Fred Isles.

855
00:30:52,779 --> 00:30:55,279
This podcast is sponsored by Elekta.

856
00:30:55,900 --> 00:30:59,039
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