The Elekta Leksell Gamma Knife Icon stereotactic radiosurgery (SRS) system has been used for the first time in the USA, on 1 March 2016 at the Sutter Medical Center, Sacramento, USA.
The patient, a 52-year-old male, from El Dorado Hills, USA, had previously undergone successful treatment for primary melanoma and for melanoma metastases to his lung. He was treated for a metastatic brain tumour. The patient’s treatment was planned and guided using a frameless approach. The frameless mask solution is one of several new features of Icon and is integrated with a novel high definition motion management. According to a company release, the system provides accuracy similar to that of frame-based SRS systems while minimising dose to normal tissue.
“Increasing the precision of frameless cranial SRS is essential for effectively targeting tumour tissue while protecting healthy brain tissue from damage,” says Samuel Ciricillo, medical director of Adult and Pediatric Neurosurgery at the Sutter Neuroscience Institute. “The new Gamma Knife system, Icon, now provides the most accurate motion tracking during treatment. Additionally, with Gamma Knife there is a two- to four-fold improvement in sparing normal brain tissue compared to other linear accelerator platforms.
These features allow for greater potential to protect patient quality of life both during treatment and after recovery.”
The Icon system will make cranial SRS available to more patients and to improve the efficacy of cranial SRS with fewer side effects, according to a company release. Icon also provides the flexibility for single dose administration or multiple treatment sessions over time, which enables treatment of larger tumour volumes, targets close to critical brain structures and new or recurring brain metastases.
At the time of SRS, pre-treatment magnetic resonance images and cone beam computed tomography (CT) images are aligned to identify precise coordinates for radiation targeting within the brain. This technology is especially important for patients who undergo multiple treatment sessions. Because the cone beam CT images are based on fixed structures within the brain, they ensure that dosage and delivery area are calculated correctly for each session, even if the patient’s head is in a slightly different position from one treatment session to another.
Ciricillo worked with Sutter Medical Center radiation oncologist Harvey Wolkov and physicist Stanley Skubic, on the procedure. They are founding members of the team that started the Sutter Gamma Knife program in 1998.
Bill Yaeger, Elekta’s executive vice president of Region North America, says, ” We are excited to be working with other leading centres across the US to install additional Gamma Knife Icon systems over the coming months.”