SVMC Radiologic Therapists Complete VisionRT Training

LinacRadOncTeam300X200Earlier this year, Southwestern Vermont Medical Center (SVMC) became one of the first hospitals in the area to be equipped with the latest in linear accelerator (linac) technology. 

More recently, SVMC’s Radiologic Therapists completed advanced training in VisionRT on the linac. 

According to Radiation Oncologist Matthew Vernon, MD, the training ensures the department is maximizing the capabilities of the technology. “In particular,” he notes, “the training in Deep Breath Hold Inspiration (DBHI) will be particularly useful in the treatment of patients with breast cancer.”

Using the technique with the VisionRT enables the radiation therapist to instruct the patient to inhale or exhale so as to move the heart away from the area to be treated. The VisionRT screen allows the therapist to see the positioning and determine when the patient is within the predetermined positional tolerance. Radiation is then administered for approximately 20 seconds at a time, with patients breathing between administrations of radiation.

The precision of the administration is important as, according to research, for left breast cancer patients, radiation therapy involving a mean dose to the heart of 3 Gy increases the patient’s risk of death from ischemic heart disease before the age of 80 years by over 26% [1]. A recent study with 20 patients being treated with DIBH led to 0% of patients exhibiting heart damage following radiation therapy [2], contrasting with a similar study showing 27% incidence of heart damage using standard methods [3].

“This technique, known as the deep-inspiration breath-hold technique, is extremely helpful in minimizing radiation exposure to healthy neighboring organs such as the heart, especially in left-sided breast cancer cases. The breath-hold lifts the breast upward away from the heart, so the exposure of the heart to radiation is minimized. I am excited our staff has completed this advanced training so we can begin utilizing some of these advanced techniques to maximize the capabilities of our technology, to the benefit of our patients.”

[1] Darby et al. Risk of Ischemic Heart Disease in Women after Radiotherapy for Breast Cancer. N Engl J Med 2013; 368:987-998

[2] As according to: ‘Prospective Assessment of Deep Inspiration Breath Hold to Prevent Radiation-Associated Cardiac Perfusion Defects in Patients with Left-Sided Breast Cancer’, T.M. Zagar et al., UNC, 2015. Full study not yet published.

[3] Marks et al. The incidence and functional consequences of RT-associated cardiac perfusion defects. Int. J. Radiation Oncology Biol. Phys., Vol. 63, No. 1, pp. 214–223, 2005