RTsafe introduces successREF, a new dosimetry audit service designed to strengthen confidence in radiotherapy beam calibration through independent, scientifically robust verification of absorbed dose under reference conditions.
Modern radiotherapy relies on increasingly complex technologies, tighter treatment margins and higher dose gradients. In this environment, confidence in beam output calibration is directly linked to patient safety, treatment quality and institutional credibility.
A relatively small deviation in absolute dose delivery may affect the entire clinical workflow. For clinicians, this translates into uncertainty regarding tumour control and normal tissue toxicity. For medical physicists, it creates additional pressure on already demanding quality assurance programmes. For hospital administrators, it introduces operational and regulatory risk, particularly as external quality standards and accreditation requirements continue to evolve.
Independent dosimetry audits have therefore become an essential component of modern radiotherapy practice. However, conventional audit approaches are often resource-intensive, time-consuming and difficult to integrate into busy clinical schedules.
RTsafe developed successREF to address these challenges. successREF is an absolute dosimetry audit service focused on verifying absorbed dose under reference conditions for megavoltage photon and electron beams. The service was designed to combine scientific rigor with operational simplicity, enabling radiotherapy centres to access independent dosimetric verification without interrupting routine clinical activity.
The added value of successREF extends beyond compliance testing. For medical physicists, the service provides an independent confirmation of beam output calibration using traceable dosimetry systems and transparent reporting. The audit supports confidence in local reference dosimetry procedures while helping identify potential inconsistencies before they can propagate into clinical treatments.
For radiation oncologists and multidisciplinary clinical teams, successREF provides reassurance that the prescribed dose is delivered accurately and consistently. In high-precision treatments, where small deviations may have a significant clinical impact, this independent verification contributes directly to safer patient care.
For hospital management and administrators, successREF offers a practical external quality assurance solution that demonstrates commitment to quality, safety and continuous improvement. The workflow minimises operational burden while supporting institutional readiness for audits, accreditation processes and regulatory expectations.
Scientific credibility was a central principle during the development of successREF. The service combines calibrated Optically Stimulated Luminescence Dosimeters (OSLDs) and Gafchromic EBT4 film dosimetry within a dedicated water equivalent phantom geometry. All detectors are calibrated in a Secondary Standard Dosimetry Laboratory (SSDL) with traceability to primary standards (BIMP France). The methodology incorporates internationally recognised reference dosimetry recommendations, including IAEA TRS – 398 and TRS – 483 for reference conditions, AAPM TG-191 guidance for OSL dosimetry and established protocols for radiochromic film analysis. Appropriate correction factors have been determined by RTsafe’s medical physics team and are applied whenever necessary. RTsafe provides the dosimeters, while the participating centre performs irradiations under reference conditions using a standard setup. The audit can be applied to standard C-arm linear accelerators, CyberKnife systems and Tomotherapy/Radixact platforms.
Figures. (a) Measurement setup in practice.(b) Irradiated film by a machine specific reference field for reference dose verification purposes
Beyond the methodology itself, RTsafe brings extensive expertise in independent radiotherapy quality assurance. The RTsafe team includes medical physicists and researchers with long-standing experience in end-to-end dosimetry audits, stereotactic radiotherapy verification, phantom development and clinical QA methodologies. RTsafe solutions are already used internationally in advanced radiotherapy applications, supporting centres in maintaining high standards of treatment accuracy.
As radiotherapy continues to advance toward greater precision and complexity, external verification of reference dosimetry becomes increasingly important. successREF reflects RTsafe’s vision of making high-level independent QA more accessible, efficient and clinically relevant.
With successREF, RTsafe aims to help radiotherapy centres strengthen confidence in one of the most fundamental elements of cancer treatment: delivering the right dose, accurately and consistently, for every patient.
AUTHOR:
Aliki Stergiou
Medical Physicist/Physics Engineer
Aliki executes current worldwide projects at RTsafe and is responsible for monitoring and supporting research and other hospital projects across Greece. She holds an Applied Mathematical and Physical Sciences diploma from the National Technical University of Athens (NTUA) and two Master’s degrees, one in Medical Physics from the National and Kapodistrian University of Athens. Aliki has a strong interest in dosimetry audits and data analysis, aiming to develop her expertise in medical physics.