Investigation of the spatial resolution of an online dose verification device

Asuni, G; Rickey, Daniel W.; McCurdy, Boyd

doi:10.1118/1.3675972

Cited by 10 publications

(7 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…suggests that a 5 mm resolution (at an isocenter) is sufficient to detect errors in IMRT delivery. Also, Asuni et al . reported the spatial resolution of the COMPASS transmission detector using narrow slit fields.…”

Section: Discussionmentioning

confidence: 99%

Validation of a method for in vivo 3D dose reconstruction in SBRT using a new transmission detector

Nakaguchi

Ono

Maruyama

et al. 2017

J Applied Clin Med Phys

View full text Add to dashboard Cite

Stereotactic body radiation therapy (SBRT) involves the delivery of substantially larger doses over fewer fractions than conventional therapy. Therefore, SBRT treatments will strongly benefit patients using vivo patient dose verification, because the impact of the fraction is large. For in vivo measurements, a commercially available quality assurance (QA) system is the COMPASS system (IBA Dosimetry, Germany). For measurements, the system uses a new transmission detector (Dolphin, IBA Dosimetry). In this study, we evaluated the method for in vivo 3D dose reconstruction for SBRT using this new transmission detector. We confirmed the accuracy of COMPASS with Dolphin for SBRT using multi leaf collimator (MLC) test patterns and clinical SBRT cases. We compared the results between the COMPASS, the treatment planning system, the Kodak EDR2 film, and the Monte Carlo (MC) calculations. MLC test patterns were set up to investigate various aspects of dose reconstruction for SBRT: (a) simple open fields (2 × 2–10 × 10 cm2), (b) a square wave chart pattern, and (c) the MLC position detectability test in which the MLCs were changed slightly. In clinical cases, we carried out 6 and 8 static IMRT beams for SBRT in the lung and liver. For MLC test patterns, the differences between COMPASS and MC were around 3%. The COMPASS with the dolphin system showed sufficient resolution in SBRT. For clinical cases, COMPASS can detect small changes for the dose profile and dose–volume histogram. COMPASS also showed good agreement with MC. We can confirm the feasibility of SBRT QA using the COMPASS system with Dolphin. This method was successfully operated using the new transmission detector and verified by measurements and MC.

show abstract

Section: Discussionmentioning

confidence: 99%

Validation of a method for in vivo 3D dose reconstruction in SBRT using a new transmission detector

Nakaguchi

Ono

Maruyama

et al. 2017

J Applied Clin Med Phys

View full text Add to dashboard Cite

show abstract

“…Some approaches lead to detailed checklists, but research has shown that a risk of “checklist fatigue” occurs when such lists grow to be too long, thus, defeating their primary purpose . Other groups have chosen to focus their efforts on the development of automated approaches, using software and/or hardware, to automatically identify potentially dangerous discrepancies . Some software approaches evaluate plan quality to ensure that planners did not inadvertently fail to achieve important quality metrics .…”

Section: Introductionmentioning

confidence: 99%

A systematic evaluation of the error detection abilities of a new diode transmission detector

Sarkar

Paxton

Kunz

et al. 2019

J Applied Clin Med Phys

View full text Add to dashboard Cite

Transmission detectors meant to measure every beam delivered on a linear accelerator are now becoming available for monitoring the quality of the dose distribution delivered to the patient daily. The purpose of this work is to present results from a systematic evaluation of the error detection capabilities of one such detector, the Delta4 Discover. Existing patient treatment plans were modified through in‐house‐developed software to mimic various delivery errors that have been observed in the past. Errors included shifts in multileaf collimator leaf positions, changing the beam energy from what was planned, and a simulation of what would happen if the secondary collimator jaws did not track with the leaves as they moved. The study was done for simple 3D plans, static gantry intensity modulated radiation therapy plans as well as dynamic arc and volumetric modulated arc therapy (VMAT) plans. Baseline plans were delivered with both the Discover device and the Delta4 Phantom+ to establish baseline gamma pass rates. Modified plans were then delivered using the Discover only and the predicted change in gamma pass rate, as well as the detected leaf positions were evaluated. Leaf deviations as small as 0.5 mm for a static three‐dimensional field were detected, with this detection limit growing to 1 mm with more complex delivery modalities such as VMAT. The gamma pass rates dropped noticeably once the intentional leaf error introduced was greater than the distance‐to‐agreement criterion. The unit also demonstrated the desired drop in gamma pass rates of at least 20% when jaw tracking was intentionally disabled and when an incorrect energy was used for the delivery. With its ability to find errors intentionally introduced into delivered plans, the Discover shows promise of being a valuable, independent error detection tool that should serve to detect delivery errors that can occur during radiotherapy treatment.

show abstract

“…Estas metodologias foram escolhidas para este trabalho por ambas dependerem da Função de Espalhamento Pontual (do inglês Point Spread Function -PSF). A PSF, que é uma função de resposta do sistema a um estímulo pontual, é amplamente utilizada em análises de resolução espacial de vários sistemas, inclusive nos de diagnóstico [3][4][5][6][7][8] .…”

Section: Introductionunclassified

Aplicação de Métodos Matemáticos para Análise de Resolução Espacial em Sensores BAC

et al. 2019

View full text Add to dashboard Cite

Neste trabalho foram analisadas as resoluções espaciais de sensores de Biosusceptometria AC (BAC) com diferentes diâmetros de bobinas e distâncias do objeto simulador. Com o uso de ferrita de manganês, como um fantoma pontual, foram adquiridas as Funções de Espalhamento Pontual dos sistemas e, através delas, foram quantificadas as resoluções dos sensores. Para isso, foram utilizados dois métodos consagrados em análise de resolução: a função de transferência modulada e a largura à meia altura. Os resultados demonstraram que para todos os diâmetros a menor distância apresentou melhores resoluções, enquanto para ambas distâncias o menor diâmetro apresentou melhores resoluções. Ao correlacionar os dois métodos para todos os casos foram obtidos perfis lineares, portanto, os métodos possuem alta similaredade quando aplicados ao sistema BAC. Com isso, podemos aferir a resolução espacial do sensor, onde foi possível realizar otimizações de geometria do sistema e posicionamentos conforme a medida a ser realizada e possíveis aplicações.

show abstract

Investigation of the spatial resolution of an online dose verification device

Cited by 10 publications

References 29 publications

Validation of a method for in vivo 3D dose reconstruction in SBRT using a new transmission detector

Validation of a method for in vivo 3D dose reconstruction in SBRT using a new transmission detector

A systematic evaluation of the error detection abilities of a new diode transmission detector

Aplicação de Métodos Matemáticos para Análise de Resolução Espacial em Sensores BAC

Contact Info

Product

Resources

About