For kids undergoing radiation therapy as part of their cancer treatment, holding still can be a challenge. Radiation therapy requires precision tumor targeting so healthy tissue around a tumor is not injured and the tumor is fully treated. That means the patient must remain still during the entire session, which can last from 20 minutes to a full hour. For kids, this can be difficult due to restlessness and short attention span, as well as anxiety, claustrophobia, and fear. General anesthesia is used when there is a concern that a patient will not be able to remain still during treatment. However, anesthesia has potential health risks, including medical risks, potential long-term neurocognitive risks, a cost to the patient and health care system, and much more time spent at the hospital.
In a new study, a video distraction intervention was found to be a successful alternative that helped some kids undergo radiation therapy while remaining still without anesthesia (Int J Radiat Oncol Biol Phys 2023; https://doi.org/10.1016/j.ijrobp.2023.03.063). "If a child can undergo radiation therapy without anesthesia while remaining calm and still, we consider this a much better way for the child to undergo treatment," said Susan Hiniker, MD, Associate Professor of Radiation Oncology at Stanford School of Medicine. She shared her thoughts on the findings.
1 Why did you and your colleagues decide to conduct this research now?
"Several years ago, we began to notice that children we saw in consultation frequently remained calm and still while we spoke with their parents, as long as the children had the ability to watch streaming video on a tablet during this time. We felt that if there was a way that children were able to be immersed in a streaming video of their choosing during daily radiation therapy (RT), with a screen in front of the child's face about the distance that a tablet might be, this might make anesthesia-free RT possible for them.
"Together, our team, including physicist Lawrie Skinner, PhD, who co-led this project together with me; Bill Loo, MD, PhD, who came up with the concept; and Sarah Donaldson, MD, who pioneered its clinical use, developed the Audio-Visual Assisted Therapeutic Ambience in Radiotherapy (AVATAR) system, which allows children to watch streaming video during RT using a portable projector mounted to the treatment table and a custom-designed radiolucent screen that does not significantly affect the radiation beam passing through it."
2 Has other research evaluated a similar type of intervention?
"There have been some previous efforts to utilize video distraction in kids undergoing RT, and ours mainly differ from those efforts through our development and use of a radiolucent screen, through which the beam can pass with minimal perturbation of dose. This allows the screen to be placed at an optimal viewing distance and position with respect to the patient to create an immersive atmosphere almost like a personal movie theater. Previous studies using video distraction generally used prefabricated screens that were not radiolucent and, therefore, had to be positioned outside of the beam at potentially suboptimal viewing angles.
"In this study, we and the 10 participating centers prospectively enrolled children ages 3-10 years preparing to undergo radiation therapy, who were able and willing to participate in three serial quality-of-life and anxiety assessments using validated metrics during their course of radiation therapy. We excluded patients for whom eye movement could potentially cause a problem to the success of their radiation therapy. We defined patients able to undergo at least one fraction of RT without anesthesia using AVATAR as successful. Patients who required anesthesia for every fraction were unsuccessful with the intervention. We defined the success of the participating center as more than 50 percent of patients being successful with the intervention.
"Among 81 children enrolled in this study, 78 percent were successful in using AVATAR to avoid anesthesia. This was significantly higher than age-matched historical controls from four previously reported cohorts in the literature, where 49 percent of similarly aged children were able to undergo RT without anesthesia. While we defined success as the ability to undergo one fraction of RT without anesthesia, it was generally much greater than that. For successful patients, anesthesia was avoided for a median of 20 fractions per patient. We also found that all 10 institutions were successful with this intervention (>50% patients at each institution successfully avoided anesthesia using AVATAR). In addition, we found that overall anxiety significantly decreased over the RT course, more in successful patients than unsuccessful patients, and quality of life improved in some subsets."
3 What is most important to know about this work?
"Incorporation of a novel video immersion system used during RT can be successfully implemented across institutions and is associated with significantly lower need for daily anesthesia as compared to historical controls. In addition, the feasibility of a supportive care intervention can be tested across multiple cooperating institutions working together to complete a study independent of any preexisting consortium.
"Our next step is two-pronged; first, we are working with collaborating centers in Tanzania, India, and Romania to study the incorporation of AVATAR into global radiation oncology centers. This is exciting to us because some centers have limited access to anesthesia and we think that AVATAR may have an even greater value in that setting. Second, we are working on further technical enhancements to the AVATAR system, including features involving two-way communication, interactive gamification, and virtual reality."