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Gafchromic film

Margherita Zani, Cinzia Talamonti, Marta Bucciolini, Marco Marinelli, Gianluca Verona-Rinati, Pierluigi Bonomo, Fabiola Paiar, Stefania Pallotta
PURPOSE: Aim of this work is the assessment of build-up and superficial doses of different clinical Head&Neck plans delivered with Helical TomoTherapy (HT) (Accuray, Sunnyvale, CA). Depth dose profiles and superficial dose points were measured in order to evaluate the Treatment Planning System (TPS) capability of an accurate dose modeling in regions of disequilibrium. Geometries and scattering conditions were investigated, similar to the ones generally encountered in clinical treatments...
October 15, 2016: Physica Medica: PM
Satish C Uniyal, Vineet Chaturvedi, Sunil D Sharma, Anurag Rawat
Cardiac interventions often result in high radiation dose to patient's skin, so a reliable indicator in terms of a commonly used dose descriptor is required to monitor skin exposures. In the present study, Gafchromic XR-RV3 film was used to measure the peak skin dose (PSD) during 40 coronary angiography (CA) and 50 percutaneous transluminal coronary angioplasty (PTCA) procedures. Corresponding values of kerma-area product (PKA), fluoroscopy time (FT) and reference air-kerma (Ka,r) were recorded and correlated with PSD...
October 15, 2016: Radiation Protection Dosimetry
L Sim
The purpose of this study was to evaluate if MED610 3D printed material can be used as a surrogate for acrylic in the manufacturing of a replacement insert used in an eye plaque brachytherapy applicator. Measurement of the dose distributions from a standard acrylic insert were compared with dose obtained from MED610 3D printed replica using GafChromic(®) EBT3 films. The study used a 15 mm Radiation Oncology Physics and Engineering Services, Australia (ROPES) type eye plaque applicator loaded with I-125 (model 6711) seeds...
October 11, 2016: Australasian Physical & Engineering Sciences in Medicine
Clara Ferreira, Daniel Johnson, Karl Rasmussen, Clinton Leinweber, Salahuddin Ahmad, Jae Won Jung
PURPOSE: To develop a novel conformal superficial brachytherapy (CSBT) device as a treatment option for the patient-specific radiation therapy of conditions including superficial lesions, postsurgical positive margins, Dupuytren's contractures, keloid scars, and complex anatomic sites (eyelids, nose, ears, etc.). METHODS AND MATERIALS: A preliminary CSBT device prototype was designed, built, and tested using readily available radioactive seeds. Iodine-125 ((125)I) seeds were independently guided to the treatment surface to conform to the target...
October 3, 2016: Brachytherapy
M F Ahmed, N Shrestha, E Schnell, S Ahmad, M S Akselrod, E G Yukihara
This work evaluates the dosimetric properties of newly developed optically stimulated luminescence (OSL) films, fabricated with either Al2O3:C or Al2O3:C,Mg, using a prototype laser scanning reader, a developed image reconstruction algorithm, and a 6 MV therapeutic photon beam. Packages containing OSL films (Al2O3:C and Al2O3:C,Mg) and a radiochromic film (Gafchromic EBT3) were irradiated using a 6 MV photon beam using different doses, field sizes, with and without wedge filter. Dependence on film orientation of the OSL system was also tested...
October 7, 2016: Physics in Medicine and Biology
Ning Wen, Siming Lu, Jinkoo Kim, Yujiao Qin, Yimei Huang, Bo Zhao, Chang Liu, Indrin J Chetty
PURPOSE: The purpose of this study is to evaluate the dosimetric uncertainty associated with Gafchromic™ (EBT3) films and establish a practical and efficient film dosimetry protocol for Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiotherapy (SBRT). METHOD AND MATERIALS: EBT3 films were irradiated at each of seven different dose levels between 1 and 15 Gy with open fields and standard deviations of dose maps were calculated at each color channel for evaluation...
October 4, 2016: Radiation Oncology
James L Grafe, Jennifer Owen, J Eduardo Villarreal-Barajas, Rao F H Khan
A new megavoltage (MV) energy was recently introduced on Varian TrueBeam linear accelerators for imaging applications. This work describes the experimental characterization of a 2.5 MV inline portal imaging beam for commissioning, routine clinical use, and quality assurance purposes. The beam quality of the 2.5 MV beam was determined by measuring a percent depth dose, PDD, in water phantom for 10 × 10 cm2 field at source-to-surface distance 100 cm with a CC13 ion chamber, plane parallel Markus chamber, and GafChromic EBT3 film...
2016: Journal of Applied Clinical Medical Physics
Grzegorz Zwierzchowski, Grzegorz Bielęda, Janusz Skowronek, Magdalena Mazur
PURPOSE: Well-known defect of TG-43 based algorithms used in brachytherapy is a lack of information about interaction cross-sections, which are determined not only by electron density but also by atomic number. TG-186 recommendations with using of MBDCA (model-based dose calculation algorithm), accurate tissues segmentation, and the structure's elemental composition continue to create difficulties in brachytherapy dosimetry. For the clinical use of new algorithms, it is necessary to introduce reliable and repeatable methods of treatment planning systems (TPS) verification...
August 2016: Journal of Contemporary Brachytherapy
A S Jagtap, T Palani Selvam, B J Patil, S T Chavan, S N Pethe, Gauri Kulkarni, S S Dahiwale, V N Bhoraskar, S D Dhole
A Telecobalt unit has wide range of applications in cancer treatments and is used widely in many countries all around the world. Estimation of surface dose in Cobalt-60 teletherapy machine becomes important since clinically useful photon beam consist of contaminated electrons during the patient treatment. EGSnrc along with the BEAMnrc user code was used to model the Theratron 780E telecobalt unit. Central axis depth dose profiles including surface doses have been estimated for the field sizes of 0×0, 6×6, 10×10, 15×15, 20×20, 25×25, 30×30cm(2) and at Source-to-surface distance (SSD) of 60 and 80cm...
September 12, 2016: Applied Radiation and Isotopes
Luis Munoz, Amy Ziebell, Jason Morton, Madhava Bhat
An in-house solution for the verification of dose delivered to a moving phantom as required for the clinical implementation of lung stereotactic ablative body radiation therapy was developed. The superior-inferior movement required to simulate tumour motion during a normal breathing cycle was achieved via the novel use of an Arduino Uno™, a low-cost open-source microcontroller board connected to a high torque servo motor. Slow CT imaging was used to acquire the image set and a 4D cone beam CT (4D-CBCT) verified the efficacy of contoured margins before treatment on the moving phantom...
September 15, 2016: Australasian Physical & Engineering Sciences in Medicine
Alexander F I Osman, Nabil Maalej, Khateeb Ul-Rahman, Wamied Abdel Rahman
We studied the effects of the presence of an air cavity and scatter due to patient size on dose distribution near an Iriduim-192 brachytherapy source (Ir-192). The source was modeled using Monte Carlo (MC) code MCNP5. The Radial dose, gL(r), and the anisotropy function, F(r,θ) specified by the AAPM TG-43 have been determined and compared with the consensus data (AAPM report No. 229). We compared our MC results to the measured dose distribution using an EBT3 Gafchromic® film measurement. The dose was determined in the presence of an air cavity of 3, 5, and 7mm diameters located at 2mm distance from Ir-192...
September 10, 2016: Physica Medica: PM
Rosalinda Ricotti, Andrea Vavassori, Alessia Bazani, Delia Ciardo, Floriana Pansini, Ruggero Spoto, Vittorio Sammarco, Federica Cattani, Guido Baroni, Roberto Orecchia, Barbara Alicja Jereczek-Fossa
PURPOSE: Dosimetric assessment of high dose rate (HDR) brachytherapy applicators, printed in 3D with acrylonitrile butadiene styrene (ABS) at different infill percentage. MATERIALS AND METHODS: A low-cost, desktop, 3D printer (Hamlet 3DX100, Hamlet, Dublin, IE) was used for manufacturing simple HDR applicators, reproducing typical geometries in brachytherapy: cylindrical (common in vaginal treatment) and flat configurations (generally used to treat superficial lesions)...
September 1, 2016: Physica Medica: PM
G P Liney, B Dong, J Begg, P Vial, K Zhang, F Lee, A Walker, R Rai, T Causer, S J Alnaghy, B M Oborn, L Holloway, P Metcalfe, M Barton, S Crozier, P Keall
PURPOSE: The pursuit of real-time image guided radiotherapy using optimal tissue contrast has seen the development of several hybrid magnetic resonance imaging (MRI)-treatment systems, high field and low field, and inline and perpendicular configurations. As part of a new MRI-linac program, an MRI scanner was integrated with a linear accelerator to enable investigations of a coupled inline MRI-linac system. This work describes results from a prototype experimental system to demonstrate the feasibility of a high field inline MR-linac...
September 2016: Medical Physics
J Greffier, G Moliner, F Pereira, L Cornillet, B Ledermann, L Schmutz, M Lomma, G Cayla, J P Beregi
To assess the interest of Gafchromic films in detection of patient's peak skin dose (PSD) in interventional cardiology. A prospective study of 112 patients was conducted (July-December 2015). Three diagnostic and therapeutic procedures were evaluated: coronary angiography (CA), coronary angiography and coronary angioplasty for one or two vessels disease (CA-PTCA) and coronary angioplasty of complex chronic total occlusion (CTO). Dosimetric indicators (DIs) were collected and PSD were measured with Gafchromic films...
August 13, 2016: Radiation Protection Dosimetry
Paul Z Y Liu, Giacomo Reggiori, Francesca Lobefalo, Pietro Mancosu, Stefano Tomatis, David R McKenzie, Natalka Suchowerska
The IBA Razor diode supersedes the IBA SFD and is intended for use in small fields. However, its behaviour in small fields has not yet been quantified. In this work, we examine the response of the Razor diode against the air core scintillation dosimeter (FOD) and Gafchromic film in photon beams from three Varian linac beams. Fields between 4mm and 30mm in width were measured, both with and without a flattening filter and at two energies. The Razor exhibited an over-response of up to 4.5% for MLC collimated fields and 7...
August 2016: Physica Medica: PM
Somayeh Gholami, Hamid Reza Mirzaei, Ali Jabbary Arfaee, Ramin Jaberi, Hassan Ali Nedaie, Seied Rabi Mahdavi, Eftekhar Rajab Bolookat, Ali S Meigooni
AIM: Verification of dose distributions for gynecological (GYN) brachytherapy implants using EBT Gafchromic film. BACKGROUND: One major challenge in brachytherapy is to verify the accuracy of dose distributions calculated by a treatment planning system. MATERIALS AND METHODS: A new phantom was designed and fabricated using 90 slabs of 18 cm × 16 cm × 0.2 cm Perspex to accommodate a tandem and Ovoid assembly, which is normally used for GYN brachytherapy treatment...
September 2016: Reports of Practical Oncology and Radiotherapy
Hali Morrison, Geetha Menon, Matthew P Larocque, Hans-Sonke Jans, Ezekiel Weis, Ron S Sloboda
PURPOSE: To estimate the total dosimetric uncertainty at the tumor apex for ocular brachytherapy treatments delivered using 16 mm Collaborative Ocular Melanoma Study (COMS) and Super9 plaques loaded with (125)I seeds in order to determine the size of the apex margin that would be required to ensure adequate dosimetric coverage of the tumor. METHODS: The total dosimetric uncertainty was assessed for three reference tumor heights: 3, 5, and 10 mm, using the Guide to the expression of Uncertainty in Measurement/National Institute of Standards and Technology approach...
August 2016: Medical Physics
Johnny E Morales, Martin Butson, Scott B Crowe, Robin Hill, J V Trapp
PURPOSE: An experimental extrapolation technique is presented, which can be used to determine the relative output factors for very small x-ray fields using the Gafchromic EBT3 film. METHODS: Relative output factors were measured for the Brainlab SRS cones ranging in diameters from 4 to 30 mm(2) on a Novalis Trilogy linear accelerator with 6 MV SRS x-rays. The relative output factor was determined from an experimental reducing circular region of interest (ROI) extrapolation technique developed to remove the effects of volume averaging...
August 2016: Medical Physics
E Mastella, S Vigorito, E Rondi, G Piperno, A Ferrari, E Strata, D Rozza, B A Jereczek-Fossa, F Cattani
PURPOSE: To evaluate the geometric and dosimetric accuracies of the CyberKnife Synchrony respiratory tracking system (RTS) and to validate a method for pretreatment patient-specific delivery quality assurance (DQA). METHODS: An EasyCube phantom was mounted on the ExacTrac gating phantom, which can move along the superior-inferior (SI) axis of a patient to simulate a moving target. The authors compared dynamic and static measurements. For each case, a Gafchromic EBT3 film was positioned between two slabs of the EasyCube, while a PinPoint ionization chamber was placed in the appropriate space...
August 2016: Medical Physics
Jamal Ahmad Mirza, Hyeonsuk Park, So-Yeon Park, Sung-Joon Ye
PURPOSE: Due to increasing demand for high-spatial resolution dosimetry, radiochromic films have been investigated as potential candidates but are often limited by the scanning system, e.g., flatbed optical scanner. In this study, Raman spectroscopy in conjunction with a microscope was selected as an alternative method for high-spatial resolution dosimetry of radiochromic film. METHODS: Unlaminated Gafchromic™ EBT3 films were irradiated with doses between 0 and 50 Gy using 6 MV x-rays of a clinical linear accelerator...
August 2016: Medical Physics
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