Characterizing local dose perturbations due to gas cavities in magnetic resonance-guided radiotherapy

Medical Physics
J ShortallM van Herk

Abstract

Due to differences in attenuation and the electron return effect (ERE), the presence of gas can increase the risk of toxicity in organs at risk (OAR) during magnetic resonance-guided radiotherapy (MRgRT). Current adaptive MRgRT workflows using density overrides negate gas from the dose calculation, meaning that the effects of ERE around gas are not taken into account. In order to achieve an accurate adaptive MRgRT treatment, we should be able to quickly evaluate whether gas present during treatment causes dose constraint violation during an MRgRT fraction. We propose an analytic method for predicting dose perturbations caused by air cavities in OARs during MRgRT. Ten virtual water phantoms were created: nine containing a centrally located spherical air cavity and a reference phantom without an air cavity. Monte Carlo dose calculations were produced to irradiate the phantoms with a single 7 MV photon beam under the influence of a 1.5 T transverse magnetic field (Monaco 5.19.02 Treatment Panning System (TPS) (Elekta AB, Stockholm, Sweden)). Dose distributions of the phantoms with and without air cavities were compared. We used a spherical coordinate system originating in the center of the cavity to sample the dose distributions a...Continue Reading

References

Feb 12, 2008·Physics in Medicine and Biology·A J E RaaijmakersJ J W Lagendijk
Aug 25, 2009·Radiotherapy and Oncology : Journal of the European Society for Therapeutic Radiology and Oncology·Marco van VulpenUulke A van der Heide
Aug 25, 2010·International Journal of Radiation Oncology, Biology, Physics·Cheng PengX Allen Li
Feb 26, 2014·Clinical Oncology : a Journal of the Royal College of Radiologists·R JadonJ Staffurth
Sep 16, 2015·Physics in Medicine and Biology·Charis KontaxisB W Raaymakers
Dec 19, 2015·International Journal of Radiation Oncology, Biology, Physics·Sahaja AcharyaJeffrey Olsen
Dec 9, 2016·Journal of Applied Clinical Medical Physics·Moti R PaudelBrian M Keller
May 24, 2018·Physics in Medicine and Biology·Robert W ChuterAlan McWilliam
Sep 12, 2018·Clinical Oncology : a Journal of the Royal College of Radiologists·A HuntS Hafeez
Sep 14, 2018·Clinical Oncology : a Journal of the Royal College of Radiologists·A CreeA McWilliam
Apr 2, 2019·The British Journal of Radiology·Ingrid M WhiteShreerang Bhide
Jul 26, 2019·Clinical and Translational Radiation Oncology·Dennis WinkelBas W Raaymakers

❮ Previous
Next ❯

Citations


❮ 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.