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FDA Public Meeting: Device Improvements to Reduce the Number of Under-Doses, Over-Doses, and Misaligned Exposures From Therapeutic Radiation. Impacting Radiotherapy Safety and QA with Device Improvements . Benedick A Fraass, PhD, FAAPM, FASTRO, FACR
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FDA Public Meeting: Device Improvements to Reduce the Number of Under-Doses, Over-Doses, and Misaligned Exposures From Therapeutic Radiation Impacting Radiotherapy Safety and QA with Device Improvements Benedick A Fraass, PhD, FAAPM, FASTRO, FACR Allen S. Lichter Professor of Radiation Oncology and Director of Radiation Physics, Dept. of Radiation Oncology, University of Michigan Chair: ASTRO Multidisciplinary QA Subcommittee AAPM Science Council, Therapy Physics Committee, TG100, Chair: Research Committee
Impacting Radiotherapy Safety and QA with Device Improvements Goal: Describe several issues in which vendor or FDA efforts may help us improve patient safety and QA efficiency and effectiveness
Need 1: Process-based Analysis + QA Imaging, Targets, Normal Anatomy, Beams Dose Calcs Plan Evaluation Inverse Planning MLC Leaf Sequencing Tx Delivery Planning, Prep Download to Delivery System Patient-specific IMRT QA • RT process is complex: we need process-oriented QA to deal with that complexity • The vendor can never “provide” all the QA needed for each potential technique • Vendors, regulators and clinicians all must recognize that we need more than just QA tests for machine features e-chart, Billing Patient Setup w/ Imaging AutomatedTx Delivery, Verification
Imaging, Targets, Normal Anatomy, Beams Dose Calcs Plan Evaluation Inverse Planning MLC Leaf Sequencing Tx Delivery Planning, Prep Patient-specific IMRT QA Download to Delivery System e-chart, Billing Patient Setup w/ Imaging AutomatedTx Delivery, Verification Need 2: Flexibility to put together new and more effective QA processes Patient-specific IMRT QA IMRT Leaf Sequencing Patient-specific IMRT QA Download to Delivery System
Need 2: Flexibility to put together new and more effective QA processes Typical Patient-Specific IMRT QA Check: • Apply IMRT plan to QA phantom • Deliver plan to QA phantom + ion chamber • Check each beam’s intensity (+ dose distrib?) vs calc (with film or 2-D electronic system) • Result: Total dose at one point + confirmation of beam intensities – after lots of work!
Need 2: Flexibility to put together new and more effective QA processes Automating Patient-Specific IMRT QA: By having the flexibility to combine devices and techniques in novel ways:
Need 2: Flexibility to put together new and more effective QA processes Automating Patient-Specific IMRT QA: Litzenberg
Need 2: Flexibility to put together new and more effective QA processes Automating Patient-Specific IMRT QA: When we are driven by clinical needs to look for better ways to do things – we need the flexibility to do things that individual vendors will not have the resources or motivation to do 4% 4%
Imaging, Targets, Normal Anat Beam Arrangement+ Technique Dose to Points Calcs Plan Evaluation MLC Leaf Sequencing Prescription, Inverse Planning MLC Leaf Sequencing Patient-specific IMRT QA Tx Delivery Planning, Prep Download to Delivery System e-chart, Billing Automated Tx Delivery, Verification (Automated) Patient Setup w/ Imaging Need 3: Flexibility to rearrange clinical process workflow The clinical workflow is directly related to the QA needed for modern RT: modifications can make crucial improvements If we identify a process change that can improve safety/quality, we need to have flexibility to implement that change We need better workflow adjustment tools...
Need 4: Vendor-provided QA Tools, Updates • Vendors must make new QA-related devices, tools, methods quickly accessible to users • Note: QA devices must be used routinely before their value, or best uses can be known or proven • FDA: A slow or difficult marketing approval process can make potential products impossible to get, test, develop or implement • This is particularly problematic for software enhancements or modifications that can fix important bugs or make a hardware device or technique useful
Imaging, Targets, Normal Anat Beam Arrangement+ Technique Dose to Points Calcs Plan Evaluation MLC Leaf Sequencing Prescription, Inverse Planning MLC Leaf Sequencing Patient-specific IMRT QA Tx Delivery Planning, Prep Download to Delivery System e-chart, Billing Automated Tx Delivery, Verification (Automated) Patient Setup w/ Imaging Need 5: Treatment Delivery QA and Monitoring: Integrated or Independent ? • Tx delivery QA and monitoring must involve RTTs and convey both qualitative + quantitative info easily and clearly • Monitoring must be integrated for efficiency • Monitoring must be independent for safety
Imaging, Targets, Normal Anat Beam Arrangement+ Technique Dose to Points Calcs Plan Evaluation MLC Leaf Sequencing Prescription, Inverse Planning MLC Leaf Sequencing Patient-specific IMRT QA Tx Delivery Planning, Prep Download to Delivery System e-chart, Billing Automated Tx Delivery, Verification (Automated) Patient Setup w/ Imaging about to move move finished Need 5: Treatment Delivery QA and Monitoring: Integrated or Independent ? (Relatively) independent verification is possible: UM CCRS System: IJROBP 95
Need 6: Collaborative + independent input into vendor design, hazard analyses, usability, and workflow efforts… • Detailed checks of software or hardware design at the end of the product development process are toolate to fix problems or weaknesses • Vendors should incorporate independent input (by clinically knowledgeable experts) into design, hazard analyses, test plan designs, usability • The earlier this happens in the development process, the better for everyone !
Need 7: Vendor support for user groups for sharing of QA methods, issues • Users of a given vendor’s system all have much in common: • QA needs and techniques • Experience with system-specific issues • Knowledge how to solve or avoid problems • Improvements to suggest • Vendors should support user’s groups which help with sharing of this info!
Impacting Radiotherapy Safety and QA with Device Improvements • Support process-based analysis and QA • Flexibility for new + more effective QA processes • Flexibility to rearrange clinical process workflow • More vendor-provided QA tools + methods • Integrated vs independent monitoring • Vendors need collaborative + independent input into design, hazard analysis, usability, workflow • Support of user groups for QA: sharing processes, methods, issues