CMC specialists show off TrueBeam system at after hours gathering

STATE OF THE ART Hope Center demonstrates radiotherapy technology

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On Thursday, lead radiation therapist Jodi Ward treated an atypical patient at the Hope Center — "Mr. Styrofoam Head."

The foam mannequin prop was used to showcase Cartersville Medical Center's TrueBeam radiotherapy system. The Varian Medical Systems unit was installed in Cartersville last year.

"A long time ago, patients would come in for whole brain radiotherapy and they would have to walk around with 'x's' on their heads and then we'd have to tape them to the table," Ward said at the Cartersville-Bartow County Chamber of Commerce-sponsored Business After Hours event. "We've come a long way in radiation therapy."

The multimillion-dollar system is one of the most advanced imaging models on the market, allowing medical care providers to treat patients with practically microscopic precision.

And it greatly expedites the process, to boot — Ward said the average treatment only takes about 15 minutes.

While the procedure itself isn't that lengthy, getting patients set up for the treatment takes considerably longer.

"It's not a very quick process, it's usually a turnaround of a week, a week and a half for a patient to get started here," Ward said. "And it's done pretty much globally that way, and it's done very accurately that way."

The process, she said, begins with a physician consulting the patient. After that, the doctor comes to the radiation therapists to set up a simulation.

"So we're going to take the patient and put them in our simulator down the hallway, where we have a normal CT scanner that you would normally [use] to have a CAT scan done," she said. "Then we take those slices of that scan we just did and we ship them over to [the dosimetrist] and we put them in our three-dimensional computer planning system."

From there, the dosimetrist meets with physicians to determine how much radiation exposure they should receive. 

"He is the one who tells me how this beam is going to aim at this patient," Ward said. "He looks out for critical structures and normal tissue. For example, in a breast patient we don't want to treat their heart or lungs. We want to treat the minimal amount of area as we can." 

That responsibility falls on the shoulders of CMC's longtime medical dosimetrist Anthony Norcross, who says the TrueBeam system is a boon to both the hospital and patients throughout northern Georgia.

"It's nice to have everything in your hometown, so you don't really have to go to other facilities or go to another state — MD Anderson or the Austin Cancer Center — to get this stuff," he said.

From there, the physician meets up with the dosimetrist one more time and a physicist is called in to check the output of the dose. That specialist does a test run without the patient present, and if it's cleared, the patient is given the green light for a formal procedure.

The system, Ward said, is used for both curative and palliative care. Treatment begins with a computer-generated mask being heated to 169 degrees Fahrenheit for 13 minutes; after it's cooled, it is affixed to the patient's face.

"The mask holds the marks and it also immobilizes them," Ward said. "We try to minimize movement in there because we want it to be accurate ... we want to treat it down to the millimeter."

The table itself is made out of carbon fiber, so it doesn't absorb any radiation. The lasers on the walls are calibrated to what are called isocenters — "which, in this case," Ward said, "is a depth inside Mr. Styrofoam's head, so that's what we calculate our dosage to."

The system also has two imaging arms — one a kilovolt imager used for things like bone injuries and the other a more powerful megavolt imager that actually delivers the stronger radiotherapy treatment.

The kilovolt imager is also capable of producing cone-beam scans, which helps the technicians with precision.

"It's kind of like a half-CT. What we do, particularly when we have a brain patient, is we would lay them on the table and cone-beam them every day before their treatment and then we would line up to their anatomy using that CT," she said. "We also  compare that to the CT we did in the simulator when we made this gentlemen his mask. We overlay those images and we match their coordinates, we match all of their anatomy to the point we're literally treating to a half-millimeter."

Once the patient is prepped and the beams are activated, the radiotherapy technicians take control of the system using a series of computer terminals, complete with a set of tablet-like devices connected to cameras within the treatment room allowing them to zoom in so close they can actually see the screws bolted into the equipment.

It might not be a life-saving amenity, per se, but the treatment does implement another piece of technology; Amazon Prime streaming audio. Ward said many patients opt for gospel music while undergoing the procedure; other times, she said she's heard heavy metal bands like AC/DC blaring out of the speakers.

Count local Chamber Executive Director Cindy Williams among those awed by the Hope Center's investment in cutting edge infrastructure — as well as their good old-fashioned bedside manner.

"I am so impressed with the innovation and the technology," she said. "And the friendliness of everybody — it truly feels like family here."