Radiation Therapy Manufacturers Readiness Check Initiatives

1. Radiation Therapy Manufacturers Readiness Check Initiatives Jim Schewe, PhD, DABMP Philips

2. Overview • Three safety initiatives introduced by Industry • Radiation Therapy Pre-Treatment Quality Assurance Verification and Approval • Verification of Beam Modifying Accessories • Patient Positioning Confirmation • Based on • Collective experience of RT vendors • Published articles on RT safety (NY Times)

3. Detailed Descriptions • Radiation Therapy Pre-Treatment Quality Assurance Verification and Approval Treatment plans are initially approved and subject to quality assurance (QA) by authorized professional personnel (e.g., physician, assigned medical physicist) before the device can deliver the treatment. With the new verification, if the system has not recorded a QA approval for an initial and/or modified treatment plan, the machine will not run until authorized professional personnel acknowledge that the QA check is complete. • Verification of Beam Modifying Accessories Beam modification techniques are essential to focusing medical radiation to kill cancer cells while minimizing damage to surrounding tissues. The enhanced beam modification check verifies the correct placement of appropriate beam modifying accessories (e.g., wedges, blocks, compensators, etc.) and prevents a machine from operating if the accessories are incorrect, missing, or out of place. • Patient Positioning Confirmation Enhancements to the treatment system will generate a visual representation of the planned relative positions of the patient and the treatment device to allow the operator to quickly compare with the patient’s actual position. The operator can confirm visually that the patient is positioned as intended in the treatment plan. The operator will then have to enter a confirmation of a positive comparison.

4. Diverse Technology Drives Implementation • Technology varies by product and vendor • So do the implementations of safety initiatives

5. Safety Initiative Implementation • The following are examples of solutions to the three initiatives • Variations by product and by vendor • Appropriate to the given technology

6. #1 Pre-Treatment QA Verification & Approval“Right plan for the right patient” • Goal: • Assure treatment cannot be performed without documented approval of treatment plan (new or modified) • Solution: • Delivery of plan requires approval by user with authorized physicist (via login & password). • The patient data record includes a record of the QA authorization for audit purposes. • Treatment cannot be delivered without approval. Figure: Plan QA Approval Check – Select to approve plan for patient delivery.

7. #1 Pre-Treatment QA Verification & Approval“Right plan for the right patient”

8. #2: Verification of Beam Modifying Accessories“Prevent beam modifier errors” • Goal: • Detect correct state (present, absent, orientation) of beam modifiers • Delivery consistent with plan • Solution: • Electrical & Mechanical Interlocks (at linac itself)

9. #2: Verification of Beam Modifying Accessories“Prevent beam modifier errors” • Goal: • Verify correct patient position, beam modifiers • Solution: • Compare reference position, modifiers, and patient identification • Addresses multiple initiatives

10. #2: Verification of Beam Modifying Accessories“Prevent beam modifier errors” • Goal: • Detect correct state (present, absent, orientation) of beam modifiers • Delivery consistent with plan • Solution: • Verify accessories (RFID and visual) • Also verify patient: this addresses #3 as well RF Sensors Camera

11. #3 Patient Positioning Confirmation“Right patient, right procedure, right site” • Goal • Verify correct patient, orientation, and position prior to treatment • Solution • Image patient at the delivery system • Compare treatment image to Planning Image & verify setup

12. #3 Patient Positioning Confirmation“Right patient, right procedure, right site” • Goal • Verify correct patient, orientation, and position prior to treatment • Solution: • Compare daily 3D image (MVCT) to original planning 3D image (kV CT) • If the operator failed to properly position the patient (i.e. ignored the display and attention prompt), the image registration would fail and the incorrect positioning is identified prior to treatment delivery.

13. #3 Patient Positioning Confirmation“Right patient, right procedure, right site” • Goal • Verify correct patient, orientation, and position prior to treatment • Solution: • Room’s Eye View (REV) • Patient orientation: • Visually via image • Orientation key (cube) • Can display • Lasers • Points of interest (tattoo marks) • Modifiers (head frame, mask) • Export to treatment system

14. #3 Patient Positioning Confirmation“Right patient, right procedure, right site”

15. Conclusions & Summary • Safety is embedded into the design of RT products • Safety initiatives have been implemented • Implementations vary by product and vendor • RT vendors have an ongoing commitment to improve safety