A Comprehensive Risk Management Framework Incorporating FMEA and Quality Indicators for Enhancing Safety during Radiation Therapy System Upgrades
Abstract
Purpose
This study aimed to enhance safety during system upgrades of radiation therapy equipment by developing a comprehensive risk management framework that incorporates Failure Mode and Effects Analysis (FMEA) and Quality Indicators (QIs). The clinical applicability and utility of this framework as a quantitative approach for evaluating operational improvements were investigated.
Methods
The proposed framework was applied to a system upgrade from TomoTherapy (Accuray) to Radixact (Accuray). A multidisciplinary team consisting of a radiation oncologist, nurse, radiation therapist, and medical physicist performed an FMEA in accordance with AAPM TG-100, and constructed a process map spanning machine acceptance through treatment initiation. Failure modes (FMs) were identified at each process step, and Risk Priority Numbers (RPNs) were calculated based on occurrence, severity, and detectability. The top 20% of high-risk FMs were selected for risk-reduction interventions. Concurrently, radiation-therapy-specific QIs proposed by Mizuno et al. were assessed before upgrade and again two months after clinical implementation, and improvement measures were undertaken for indicators with insufficient achievement. Changes in RPNs and QI achievement rates before and after the upgrade were compared, and their relationship was evaluated.
Results
Twenty processes were identified, yielding 214 FMs. Among these, 42 high-risk FMs were prioritized, and their mean RPN decreased markedly from 149.4 to 68.3 following the upgrade, demonstrating substantial risk reduction. The QI achievement rate improved from 46% pre-upgrade to 77% post-implementation. Moreover, the trend in RPNs sreduction was consistent with improvements in QI performance.
Conclusion
The comprehensive risk management framework that incorporates FMEA and QIs demonstrated clinical value by improving safety during a system upgrade and enabling quantitative assessment of risk-reduction effects. This methodology may be applicable to new equipment installations and operational transitions, contributing to continuous quality management in radiation therapy.