Note: The animation has been setup to continuously loop. The animation is intended to allow the audience to pass the time while the room fills. Note that RapidArc treatment delivery requires one single rotation of the gantry.
Over last 12 yrs or so, Varian has made great progress in developing systems for more conformal therapy. Starting in the early 90s with IMRT which automatically shaped the beam to match the shape of the tumor, to IGRT which added imaging devices on the machine to target tumor more accurately, to SRS which uses this precision to complete treatments of small tumors and metastatic lesions in only 1-5 sessions. Institutions have been able to attract more patients with these new capabilities, achieving higher revenue streams and obtaining a ROI in as little as 12-18 mos.
RapidArc does not require major process changes from the physician, physicist, dosimetrist or therapist. While the treatment time is much faster, the steps for planning and delivering treatments are virtually the same as today’s IMRT and IGRT treatment techniques. As a result, a single arc can deliver essentially similar dose distributions compared with IMRT plans that incorporate as many as 36 fields.
Objectives: increase dose conformity and tissue sparing while reducing plan complexity, treatment time and risk of secondary cancer Major benefit of RapidArc is actually SPEED (when differentiated against existing techniques). This is a testament to the quality of standard IMRT approaches, there is little room for improvement in plan quality using external beam radiation.
The perfect treatment system must be fast, efficient, and simple for a clinician to implement without compromise. It must support the full range of treatment options from basic conformal therapy to IMRT, to IGRT, and SRS. It should have electron and photon beams, multiple beam energies, and thousands upon thousands of beam angles. To meet state-of-the art requirements in treatment precision, this treatment system must have efficient motion management and multiple imaging modalities, including fast radiographic, fluoroscopic and 3D cone beam CT. It must be a solid investment – offering real value in price and service and a rapid ROI. Finally, it must have ability to be upgraded easily with new technology in order to keep it state of the art.
Note that a complete RapidArc treatment, including imaging and patient positioning, can be completed in just over 3 minutes. This is possible by taking advantage of many of the characteristics of Varian&apos;s current range of linear accelerators and multileaf collimators, including: Leaf interdigitation uniquely possible with a Varian multileaf collimator Varian&apos;s dynamic &quot;sliding window&quot; approach to beam shaping The Varian patented &quot;gridded gun&quot; to vary the dose rate as a function of the gantry angle
What is the importance of treatment time? The reduction of patient motion or the “wiggle” factor. When a patient is placed on the table, in even the best of immobile devices, we still rely on the patient to lie still throughout the entire treatment so that we can measure and monitor the patient position with optical guidance type of systems. By decreasing the treatment time, we can decrease the occurrence of patient motion. This also includes internal motions such as peristaltic motions and other motions that occur on long timescales. The shorter the treatment time, the less these effects come into play. Certainly treatment time is important from the standpoint of patient comfort.
The unique differentiating value proposition of RapidArc is that it simultaneously achieves fastest treatments, most conformal dose distribution (precision), efficient delivery (low MU), and simple planning and delivery. No other vendor/technique offers all 4 values in one solution. Other solutions might match RapidArc in conformity, efficiency, or simplicity, but with a trade off in one of the other categories. RapidArc allows for treatment without compromise.
RapidArc PowerPoint Presentation
Vasthi Wilson, MD, MSc
New Jersey Health Network
Egg Harbor Township, NJ
The Evolution of Arc Therapy
I M P R O V I N G P R E C I S I O N A N D S P E E D
Dynamic Conformal Arcs
Slice Based Arcs
RapidArc Treatment Time
– Treat 16 more patients per day
• Increase from 32 to 48 treatments
• 15 minute standard treatment schedule
• 10 minute RapidArc treatment schedule
• Make time for more complex treatments
• SRS, IGRT, DART™ dynamic adaptive radiation
• Dose conformity
• Tissue sparing
• Plan complexity
• Treatment time
• Risk of secondary
RapidArc Reduced Risk
• 30-60% fewer monitor units
– Lower risk of secondary
– Less head scatter
– Less MLC leakage
• Treat in under 2 minutes
• Reduce out of field dose
• Simple planning and treatment
• Large treatment volume
• No compromises