Edge effects in 3D dosimetry: characterisation and correction of the non-uniform dose response of PRESAGE®

Physics in Medicine and Biology
F CostaU Oelfke

Abstract

Previous work has shown that PRESAGE® can be used successfully to perform 3D dosimetric measurements of complex radiotherapy treatments. However, measurements near the sample edges are known to be difficult to achieve. This is an issue when the doses at air-material interfaces are of interest, for example when investigating the electron return effect (ERE) present in treatments delivered by magnetic resonance (MR)-linac systems. To study this effect, a set of 3.5 cm-diameter cylindrical PRESAGE® samples was uniformly irradiated with multiple dose fractions, using either a conventional linac or an MR-linac. The samples were imaged between fractions using an optical-CT, to read out the corresponding accumulated doses. A calibration between TPS-predicted dose and optical-CT pixel value was determined for individual dosimeters as a function of radial distance from the axis of rotation. This data was used to develop a correction that was applied to four additional samples of PRESAGE® of the same formulation, irradiated with 3D-CRT and IMRT treatment plans, to recover significantly improved 3D measurements of dose. An alternative strategy was also tested, in which the outer surface of the sample was physically removed prior to irradi...Continue Reading

References

Aug 15, 2002·Radiotherapy and Oncology : Journal of the European Society for Therapeutic Radiology and Oncology·Tom DepuydtDominique Pierre Huyskens
Nov 9, 2006·Medical Physics·Pengyi GuoMark Oldham
Dec 18, 2008·Physics in Medicine and Biology·Stephen G BosiClive Baldock
Feb 13, 2010·Physics in Medicine and Biology·C BaldockL J Schreiner
Jun 28, 2011·Physics in Medicine and Biology·A T Abdul RahmanSimon J Doran
Jul 23, 2011·Medical Physics·Andre MickeXiang Yu
Dec 12, 2012·Physics in Medicine and Biology·Jan Vandecasteele, Yves De Deene
Jun 10, 2014·Medical Dosimetry : Official Journal of the American Association of Medical Dosimetrists·Kieyin TengMoshi Geso
Feb 17, 2015·Physics in Medicine and Biology·Jake JacksonMark Oldham
May 17, 2017·Journal of Cancer Research and Therapeutics·Murugesan KathirvelSubramanian Kala
Sep 7, 2017·Medical Physics·Stewart MeinMark Oldham
Oct 2, 2017·Radiotherapy and Oncology : Journal of the European Society for Therapeutic Radiology and Oncology·Hannah J LeeGeoffrey S Ibbott

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.