Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Aug;46(8):926-932.
doi: 10.15537/smj.2025.46.8.20240844.

Effectiveness of EPID-based in-vivo dosimetry with EPIgray® Software for head and neck VMAT treatments

Ghassan Al-Murshedi  1 , Yasmin Md Radzi  1 , Noor Naslinda Noor Rizan  1 , Azhar Abdul Rahman  1
Affiliations

Effectiveness of EPID-based in-vivo dosimetry with EPIgray® Software for head and neck VMAT treatments

Ghassan Al-Murshedi et al. Saudi Med J. 2025 Aug.

Abstract

Objectives: To evaluate the effectiveness of in-vivo dosimetry (IVD) utilizing an electronic portal imaging device (EPID) in conjunction with EPIgray® software (DOSIsoft, Cachan, France) for assessing the accuracy of dose delivery for the patient when undertaking head and neck (H&N) treatments.

Methods: Using cross-sectional analysis, data were collected from the linear accelerator of twenty patients undergoing (H&N) radiotherapy treatments using the Volumetric Modulated Arc Therapy (VMAT) modality from June 2019 to October 2023 at Gleneagles Hospital Penang, Penang, Malaysia. EPIgray® software reconstructed the delivered dose based on EPID images. These reconstructed doses were compared with the planned doses to evaluate dose accuracy, specifically looking at how many patient doses fell within the set tolerance range. In addition, RTsafe PseudoPatient™ phantom was involved in this study, and the reconstructed dose with EPIgray® was compared with the delivered dose and was established as a benchmark for accuracy.

Results: The percentage difference between the reconstructed doses and planned doses (ΔD%) for patients ranged from (1.96) to (-11.1), and the results showed that 60% of the patients' doses were within the tolerance range (±5%). The phantom study resulted in a percentage dose difference (ΔD%) of -1.73%, and this was established as a benchmark for accuracy.

Conclusion: The study proves that using EPID-based in-vivo dosimetry with EPIgray® software is a precise way to check that the right amount of radiation is being delivered for patients during radiotherapy to head and neck (H&N) treatments. Integrating EPIgray® into clinical practice enhances dose accuracy and patient safety.

Keywords: EPIgray®; PseudoPatient™ phantom; Radiotherapy; Volumetric Modulated Arc Therapy (VMAT).

PubMed Disclaimer

Figures

Figure 1
Figure 1
- Illustrates RTsafe PseudoPatient™ phantom (left) and VMAT planning (right).
Figure 2
Figure 2
- Illustrates RTsafe PseudoPatient ™ phantom (RTsafe. P.C., Athens, Greece).
Figure 3
Figure 3
- Percentage dose difference (ΔD%) for patients and RTsafe PseudoPatient™ phantom.
Figure 4
Figure 4
- Distribution of the points of interest for EPIgray Software in RTsafe Phantom.
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Bartnikowska A, Cieślik G, Młodzik M, Garcia-Argibay M.. Comparison of pre-treatment and in-vivo dosimetry for advanced radiotherapy of prostate cancer. Rep Pract Oncol Radiother 2022; 27: 189-197. - PMC - PubMed
    1. IAEA. Development of procedures for in vivo dosimetry in radiotherapy. Vienna, Austria: International Atomic Energy Agency, IAEA; 2013.
    1. Petoukhova A, Snijder R, Vissers T, Ceha H, Struikmans H.. In vivo dosimetry in cancer patients undergoing intraoperative radiation therapy. Phys Med Biol 2023; 68: 18TR01. - PubMed
    1. Kutuzov I, Rivest R, VanUytven E, McCurdy B.. Long-term performance monitoring of a-Si 1200 electronic portal imaging device for dosimetric applications. J Appl Clin Med Phys 2024; 26: e14551. - PMC - PubMed
    1. Avelino SR, Dias JR, Peron TM, Vidal GS.. Evaluation of an EPID in vivo monitoring system using local and external independent audit measurements. J Appl Clin Med Phys 2022; 23: e13822. - PMC - PubMed

LinkOut - more resources