Ehime University Hospital has over three years experience of using the Delta4 Discover for pre treatment QA and in-vivo dosimetry.

Interview with Dr. Hirofumi Honda, chief physicist at the Ehime University Hospital in Japan, about their daily work with a transmission detector.

Delta4 Discover user since 2017.
"Our department has two physicists and three technologists who are responsible for performing treatment and QA on our two linacs, TrueBeam and Clinic IX. We treat 385 new patients per year, in total 515 including recurrence patients. We have used the Delta4 Discover clinically since November 2017. We use it in two ways: as a QA tool during treatment to confirm the dose in the patient and as a pre-treatment verification tool.
We use the Delta4 Discover to improve patient safety
Prior incidents show us that pre-treatment verification cannot detect errors during treatment, so we use the Delta4 Discover to improve patient safety. By using the Delta4 Discover during treatment we can confirm the actual dose in the patient.


Treatment adaptability without any stress and extra efforts.
The real-time dose verification from the Delta4 Discover plays an important role when physicians do treatment planning. They can adapt the plan if they find out that any errors have occurred during treatment. Thanks to the Delta4 Discover´s ability to detect errors immediately after treatment we can perform treatments without any stress and extra efforts like re-calculations.


A good reference for Machine QA.
We have not tried yet but we have high expectations for using the Delta4 Discover as a Machine QA tool for linac systems and VMAT observing the trends. Today the Delta4 Discover can analyze the MLC position errors precisely and detect errors in the DD, DTA, and Gamma. It can also judge the source of errors like MLC position errors, dose, effects of gantry, and collimator angles. It will help us guarantee the dose to the patient and also be a good reference for Machine QA."


About Delta4 Discover
An ultra‐thin transmission detector which enables users to perform everything from machine QA to dose delivery verification at treatment. Ensures patients are treated according to plan while immediately detecting errors. Approved for use by Varian on TrueBeam and Clinac systems. Learn more


About Ehime University Hospital
The Ehime University Hospital’s mission is to provide undergraduate and graduate school education to students and medical personnel, and carry out research and development efforts aimed at the fostering of high-quality medicine and advancements in medicine and medical treatments. The Hospital includes 24 departments, 42 central care facilities and 644 beds. It employs more than 500 doctors, approximately 700 nurses, and various other staff for a total personnel force of just under 2,000 people.