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Bajpai V, Raval V, Reddy P VA, Kaliki S. Ruthenium-106 ( 106Ru) plaque brachytherapy for treatment of circumscribed choroidal hemangioma. Eur J Ophthalmol 2024:11206721241257974. [PMID: 38794917 DOI: 10.1177/11206721241257974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2024]
Abstract
PURPOSE To describe the clinical and imaging features of circumscribed choroidal hemangiomas (CCH) and their treatment outcomes with Ruthenium-106 (106Ru) plaque brachytherapy. METHODS Retrospective study of 24 patients (24 eyes) diagnosed with CCH and treated with 106Ru plaque between 2017 and 2022. Analysis included pre- and post-treatment clinical and imaging features such as tumor regression, reduction in height, subretinal fluid (SRF) resolution, and change in best-corrected visual acuity (BCVA). RESULTS The mean age at presentation was 36 years (range, 16-57). The most common tumor location was the temporal quadrant (n = 19) with macular involvement (n = 13). Associated features were macular SRF (n = 22) and inferior exudative retinal detachment (n = 10). Nineteen of the 24 patients underwent primary treatment, whereas 5 patients underwent plaque as a salvage treatment. The mean tumor apex dose was 40 Gy. At a median follow-up of 7.5 months (range 3-65 months), 18 eyes showed complete regression, whereas 6 eyes showed partial regression. The mean height decreased from 4.8 (SD 1.28) mm at presentation to 2.5 (SD 1.63) mm. Median BCVA improved from logMAR 1.2 (IQR 0.4-2) at baseline to logMAR 1.05 (IQR 0.1-1.95) (p = 0.4). Complete resolution of the macula and tumor SRF was observed in 15 (68%) and 13 (57%) eyes, respectively. The radiation-related complications observed were radiation maculopathy (4 eyes), retinopathy (1 eye), and vitreous hemorrhage (1 eye). CONCLUSION Ruthenium-106 plaque brachytherapy is effective for CCH (> 3 mm height) as a primary and salvage treatment for tumors unresponsive to other modalities.
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Affiliation(s)
- Vidhi Bajpai
- Anand Bajaj Retina Institute, L.V. Prasad Eye Institute, Hyderabad, India
| | - Vishal Raval
- Anand Bajaj Retina Institute, L.V. Prasad Eye Institute, Hyderabad, India
- The Operation Eyesight Universal Institute for Eye Cancer, L.V. Prasad Eye Institute, Hyderabad, India
| | - Vijay Anand Reddy P
- The Operation Eyesight Universal Institute for Eye Cancer, L.V. Prasad Eye Institute, Hyderabad, India
| | - Swathi Kaliki
- The Operation Eyesight Universal Institute for Eye Cancer, L.V. Prasad Eye Institute, Hyderabad, India
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Wang W, Emrich J, Mourtada F. Novel 3D printed universal conical holder for eye plaque quality assurance. J Appl Clin Med Phys 2024:e14395. [PMID: 38742823 DOI: 10.1002/acm2.14395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 03/31/2024] [Accepted: 04/18/2024] [Indexed: 05/16/2024] Open
Abstract
PURPOSE For the custom-built construction of eye plaques, the iodine (I-125) seeds of different source strengths are recycled in our eye plaque program. To return I-125 seeds to the correct lot, we developed a novel 3D-printed conical plaque QA holder for relative assay for eye plaques. MATERIALS AND METHODS A universal 3D-printed conical plaque holder was designed to accommodate six plaque sizes and fit reproducibly in a well-type dose calibrator. A reproducibility test was used to compare the plaque placement consistency in the holder versus without the holder. Plaque assays were performed for assembled plaques both before implant and after explant. The explant reading was compared with the implant reading adjusted for decay, and the relative error was calculated. The plaque response fraction (PRF) is defined as the fraction of well chamber implant reading over the total seed strength for a plaque. The PRF was aggregated for each individual plaque to confirm the seed lot before implant. RESULTS The reproducibility test showed the chamber reading's relative standard deviation of 0.40% with the QA holder compared to 0.68% without it. The batch relative assay was performed for 251 plaques. The absolute value of measurement deviation between explant and decay-corrected implant readings is 0.89% ± 0.86% (mean ± standard deviation). The PRFs for individual plaques range from 36.49% to 49.87%, with a maximum standard deviation of 2%. CONCLUSIONS This novel 3D-printed QA holder provides reproducible setup for assaying assembled eye plaques in a well chamber. Batch relative assay can validate the seed batch used and plaque integrity during the implant without assaying individual seeds, saving valuable physicist time and radiation exposure from seed handling.
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Affiliation(s)
- Wentao Wang
- Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | | | - Firas Mourtada
- Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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Lalos F, Flühs D, Guberina M, Bornfeld N, Stuschke M, Sauerwein W, Bechrakis NE. Tumor- and Radiation-Related Complications after Ruthenium-106 Brachytherapy in Small to Medium Uveal Melanomas (Part 1). Klin Monbl Augenheilkd 2024. [PMID: 38354842 DOI: 10.1055/a-2268-0985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2024]
Abstract
PURPOSE The purpose of this study was to analyze tumor-related complications after ruthenium-106 brachytherapy in patients with uveal melanoma, with respect to local tumor control, insufficient radiation response, enucleation, and metastasis rate. PATIENTS/METHODS AND MATERIALS This retrospective study included 608 patients treated consecutively with ruthenium-106 brachytherapy between January 2008 and December 2010 at the Department of Ophthalmology, University Hospital Essen. The occurrence of radiation-induced results was analyzed by estimating the risk by applying the Kaplan-Meier method, i.e., the "time to event" analysis. The Cox model test was used for the univariate and multivariate risk factor analyses. The median follow-up was 51 months after primary treatment. RESULTS Tumor recurrence was found in 21 patients (3.5%) and repeated treatment due to insufficient effect after the initial ruthenium-106 brachytherapy was performed in 40 patients (6.6%). The 5-year cumulative risk of recurrence was 4.0% and that of insufficient effect was 7.3%. Thirteen patients (2.1%) underwent a secondary enucleation; 8 because of a local recurrence and 5 because of severe post-brachytherapy complications. The cumulative enucleation risk was 2.3% after 5 years and 2.9% after 10 years, corresponding to eye preservation of 97.7 and 97.1%, respectively. In forty-two patients (7.2%), metastatic disease was diagnosed during the follow-up. The metastatic rate as calculated by the Kaplan-Meier method was 9.0, and 13.1% at 5 and 10 years, respectively. CONCLUSION Our study demonstrated that ruthenium-106 brachytherapy is an excellent treatment option for achieving local tumor control and eye preservation in well-selected patients. The metastatic rate is in agreement with that of previous studies analyzing small to medium size uveal melanomas.
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Affiliation(s)
- Fotios Lalos
- Department of Ophthalmology, University Hospital of Essen, Germany
| | - Dirk Flühs
- Department of Radiotherapy, University Hospital of Essen, Germany
| | - Maja Guberina
- Department of Radiotherapy, University Hospital of Essen, Germany
| | - Norbert Bornfeld
- Department of Ophthalmology, University Hospital of Essen, Germany
| | - Martin Stuschke
- Department of Radiotherapy, University Hospital of Essen, Germany
- German Cancer Consortium (DKTK), Heidelberg, Partner Site University Hospital Essen, Essen, Germany
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Chvetsov AV. Equivalent uniform RBE-weighted dose in eye plaque brachytherapy. Med Phys 2024; 51:3093-3100. [PMID: 38353266 DOI: 10.1002/mp.16982] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/22/2023] [Accepted: 01/30/2024] [Indexed: 04/05/2024] Open
Abstract
BACKGROUND Brachytherapy for ocular melanoma is based on the application of eye plaques with different spatial dose nonuniformity, time-dependent dose rates and relative biological effectiveness (RBE). PURPOSE We propose a parameter called the equivalent uniform RBE-weighted dose (EUDRBE) that can be used for quantitative characterization of integrated cell survival in radiotherapy modalities with the variable RBE, dose nonuniformity and dose rate. The EUDRBE is applied to brachytherapy with 125I eye plaques designed by the Collaborative Ocular Melanoma Study (COMS). METHODS The EUDRBE is defined as the uniform dose distribution with RBE = 1 that causes equal cell survival for a given nonuniform dose distribution with the variable RBE > 1. The EUDRBE can be used for comparison of cell survival for nonuniform dose distributions with different RBE, because they are compared to the reference dose with RBE = 1. The EUDRBE is applied to brachytherapy with 125I COMS eye plaques that are characterized by a steep dose gradient in tumor base-apex direction, protracted irradiation during time intervals of 3-8 days, and variable dose-rate dependent RBE with a maximum of about 1.4. The simulations are based on dose of 85 Gy prescribed to the farthest intraocular extent of the tumor (tumor apex). To compute the EUDRBE in eye plaque brachytherapy and correct for protracted irradiation, the distributions of physical dose have been converted to non-uniform distributions of biologically effective dose (BED) to include the biological effects of sublethal cellular repair, Our radiobiological analysis considers the combined effects of different time-dependent dose rates, spatial dose non-uniformity, dose fractionation and different RBE and can be used to derive optimized dose regimens brachytherapy. RESULTS Our simulations show that the EUDRBE increases with the prescription depths and the maximum increase may achieve 6% for the tumor height of 12 mm. This effect stems from a steep dose gradient within the tumor that increases with the prescription depth. The simulations also show that the EUDRBE increase may achieve 12% with increasing the dose rate when implant duration decreases. The combined effect of dose nonuniformity and dose rate may change the EUDRBE up to 18% for the same dose prescription of 85 Gy to tumor apex. The absolute dose range of 48-61 Gy (RBE) for the EUDRBE computed using 4 or 5 fractions is comparable to the dose prescriptions used in stereotactic body radiation therapy (SBRT) with megavoltage X-rays (RBE = 1) for different cancers. The tumor control probabilities in SBRT and eye plaque brachytherapy are very similar at the level of 80% or higher that support the hypothesis that the selected approximations for the EUDRBE are valid. CONCLUSIONS The computed range of the EUDRBE in 125I COMS eye plaque brachytherapy suggests that the selected models and hypotheses are acceptable. The EUDRBE can be useful for analysis of treatment outcomes and comparison of different dose regimens in eye plaque brachytherapy.
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Affiliation(s)
- Alexei V Chvetsov
- Department of Radiation Oncology, University of Washington, Seattle, Washington, USA
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De Brabandere M, Placidi E, Siebert FA, Carlsson Tedgren Å, Slocker Escarpa A, Tagliaferri L, Andrássy M, Schulz C, Fog LS. GEC-ESTRO survey of 106Ru eye applicator practice for ocular melanoma - Physicist survey. Radiother Oncol 2024; 193:110114. [PMID: 38309583 DOI: 10.1016/j.radonc.2024.110114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/16/2024] [Accepted: 01/27/2024] [Indexed: 02/05/2024]
Abstract
AIM 106Ru eye plaque brachytherapy (BT, interventional radiotherapy) is an eye-preserving treatment for uveal melanoma performed in about 100 clinics worldwide. Despite this relatively low number, there is a considerable variation in clinical practice. In 2022, the BRAPHYQS and Head & Neck and Skin GEC-ESTRO working groups conducted a survey to map the current clinical practice. The survey consisted of a physicist and a physician part. This paper describes the physicist results. However, three physician questions with overlapping interest are included here as well. MATERIALS AND METHODS The survey questions pertained to commissioning and quality control (QC) of the plaques, treatment planning, radiobiological correction, as well as more general questions on practice improvement. The questions overlapping with the physician survey were related to dose prescription and margins. RESULTS Sixty-five physicist responses were included. A majority of the centres do not perform an independent measurement of the absorbed dose at reference depth, percentage depth dose (PDD) and off-axis data. A lack of calibration services and suitable equipment are the main reasons. About one third of the centres indicated that they do image based treatment planning. The use of margins and dose prescription showed a large variability, despite the availability of guidelines [1]. Many respondents expressed a strong wish for improvement in a wide range of aspects of clinical practice. CONCLUSION The physics survey showed a wide variability regarding quality control of the 106Ru sources and treatment planning practice.
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Affiliation(s)
| | - Elisa Placidi
- UOC Physics for Life Sciences, Diagnostic Imaging, Oncologic Radiotherapy and Hematology, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy
| | - Frank-André Siebert
- Clinic of Radiotherapy (Radiooncology), University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Åsa Carlsson Tedgren
- Radiation Physics, Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden; Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm, Sweden; Department of Oncology Pathology, Karolinska Institute, Stockholm, Sweden
| | | | - Luca Tagliaferri
- Fondazione Policlinico Universitario A. Gemelli IRCCS, Gemelli ART (Advanced Radiation Therapy), Interventional Oncology Center (IOC), Rome, Italy
| | - Michael Andrássy
- Eckert & Ziegler BEBIG GmbH, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Carmen Schulz
- Eckert & Ziegler BEBIG GmbH, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Lotte S Fog
- Ocular oncology unit, Royal Victorian Eye and Ear Hospital, Melbourne, Australia; Alfred Health Radiation Oncology, Melbourne, VIC, Australia
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Mobit P, Yang CC, Nittala MR, He R, Ahmed HZ, Shultz G, Lin A, Vijayakumar S. Eye Plaque Brachytherapy for Choroidal Malignant Melanoma: A Case Report on the Use of Innovative Technology to Expand Access, Improve Practice, and Enhance Outcomes. Cureus 2024; 16:e54572. [PMID: 38524010 PMCID: PMC10957294 DOI: 10.7759/cureus.54572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2024] [Indexed: 03/26/2024] Open
Abstract
Our institute established an eye plaque interstitial brachytherapy (EPIBT) program in 2007 using the Collaborative Ocular Melanoma Study (COMS) eye plaque. In this case report, we demonstrated an eye plaque treatment planned and executed using Eye Physics Plaque (Los Alamitos, CA) for a 72-year-old male patient with an extra-large tumor with a maximum width of 18.6 mm and height of 13.7 mm. The use of a customized eye plaque, manufactured through three-dimensional (3D) printing, has empowered us to plan and administer treatment for this patient with uveal melanoma. Without this option, enucleation, an option declined by the patient, or proton beam therapy (PBT), which the patient was unwilling to pursue in another state, would have been the alternative course of action. We were able to use more than one activity of the I-125 seeds, which enabled us to shape and reduce the dose to normal surrounding structures at risk within the orbit and in the vicinity of the orbital cavity. Using the dose evaluation tools available with the modern treatment planning system, we reduced the prescription dose from 85 to 70 Gy, with D90 of 140 Gy, thereby providing effective treatment and limiting risk organ doses. In summary, we were able to dose-deescalate without compromising the chances of controlling retinal/scleral tumors. The patient is doing well from a recent follow-up visit 12 months after the eye plaque brachytherapy treatment. The tumor was 4.80 mm high, 1/3 of the original height, and vision is back to 20/60, demonstrating a successful treatment.
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Affiliation(s)
- Paul Mobit
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Claus Chunli Yang
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Mary R Nittala
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Rui He
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Hiba Z Ahmed
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Gary Shultz
- Radiation Oncology, G.V. (Sonny) Montgomery VA Medical Center, Jackson, USA
| | - Albert Lin
- Ophthalmology, University of Mississippi Medical Center, Jackson, USA
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Fletcher EM, Ballester F, Beaulieu L, Morrison H, Poher A, Rivard MJ, Sloboda RS, Vijande J, Thomson RM. Generation and comparison of 3D dosimetric reference datasets for COMS eye plaque brachytherapy using model-based dose calculations. Med Phys 2024; 51:694-706. [PMID: 37665982 DOI: 10.1002/mp.16721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 08/06/2023] [Accepted: 08/15/2023] [Indexed: 09/06/2023] Open
Abstract
PURPOSE A joint Working Group of the American Association of Physicists in Medicine (AAPM), the European Society for Radiotherapy and Oncology (ESTRO), and the Australasian Brachytherapy Group (ABG) was created to aid in the transition from the AAPM TG-43 dose calculation formalism, the current standard, to model-based dose calculations. This work establishes the first test cases for low-energy photon-emitting brachytherapy using model-based dose calculation algorithms (MBDCAs). ACQUISITION AND VALIDATION METHODS Five test cases are developed: (1) a single model 6711 125 I brachytherapy seed in water, 13 seeds (2) individually and (3) in combination in water, (4) the full Collaborative Ocular Melanoma Study (COMS) 16 mm eye plaque in water, and (5) the full plaque in a realistic eye phantom. Calculations are done with four Monte Carlo (MC) codes and a research version of a commercial treatment planning system (TPS). For all test cases, local agreement of MC codes was within ∼2.5% and global agreement was ∼2% (4% for test case 5). MC agreement was within expected uncertainties. Local agreement of TPS with MC was within 5% for test case 1 and ∼20% for test cases 4 and 5, and global agreement was within 0.4% for test case 1 and 10% for test cases 4 and 5. DATA FORMAT AND USAGE NOTES Dose distributions for each set of MC and TPS calculations are available online (https://doi.org/10.52519/00005) along with input files and all other information necessary to repeat the calculations. POTENTIAL APPLICATIONS These data can be used to support commissioning of MBDCAs for low-energy brachytherapy as recommended by TGs 186 and 221 and AAPM Report 372. This work additionally lays out a sample framework for the development of test cases that can be extended to other applications beyond eye plaque brachytherapy.
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Affiliation(s)
- Elizabeth M Fletcher
- Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, Ottawa, Ontario, Canada
| | - Facundo Ballester
- Departamento de Física Atómica, Molecular y Nuclear, Universitat de Valencia (UV), Burjassot, Spain
- Unidad Mixta de Investigación en Radiofísica e Instrumentación Nuclear en Medicina (IRIMED), Instituto de Investigación Sanitaria La Fe (IIS-La Fe)-Universitat de Valencia (UV), Burjassot, Spain
| | - Luc Beaulieu
- Service de physique médicale et Axe oncologie du Centre de recherche du CHU de Québec, CHU de Québec, Québec, Québec, Canada
- Département de Physique, de Génie Physique et d'Optique et Centre de Recherche sur le Cancer, Université Laval, Québec, Québec, Canada
| | - Hali Morrison
- Department of Oncology and Department of Physics and Astronomy, University of Calgary, Calgary, AB, Canada
- Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta, Canada
| | - Audran Poher
- Service de physique médicale et Axe oncologie du Centre de recherche du CHU de Québec, CHU de Québec, Québec, Québec, Canada
- Département de Physique, de Génie Physique et d'Optique et Centre de Recherche sur le Cancer, Université Laval, Québec, Québec, Canada
| | - Mark J Rivard
- Department of Radiation Oncology, Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | - Ron S Sloboda
- Department of Medical Physics, Cross Cancer Institute, Edmonton, Alberta, Canada
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada
| | - Javier Vijande
- Departamento de Física Atómica, Molecular y Nuclear, Universitat de Valencia (UV), Burjassot, Spain
- Unidad Mixta de Investigación en Radiofísica e Instrumentación Nuclear en Medicina (IRIMED), Instituto de Investigación Sanitaria La Fe (IIS-La Fe)-Universitat de Valencia (UV), Burjassot, Spain
- Instituto de Física Corpuscular, IFIC (UV-CSIC), Burjassot, Spain
| | - Rowan M Thomson
- Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, Ottawa, Ontario, Canada
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Chang X, Huang L, Liu J, Cao Y, Chang J. Monte Carlo dosimetry of a novel Yttrium-90 disc source for episcleral brachytherapy. J Appl Clin Med Phys 2023; 24:e14140. [PMID: 37708092 PMCID: PMC10691622 DOI: 10.1002/acm2.14140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 08/10/2023] [Accepted: 08/11/2023] [Indexed: 09/16/2023] Open
Abstract
PURPOSE To calculate the dose distribution using Monte Carlo simulations for a novel high-dose-rate Yttrium-90 (Y-90) disc source recently developed for episcleral brachytherapy and provide a lookup table for treatment planning. METHODS Monte Carlo simulations were performed to calculate the in-water dose distribution of the Y-90 disc source using the "GATE", a software based on the "Geant4" Monte Carlo simulation toolkit developed by the international OpenGATE collaboration. The geometry of this novel beta source, its capsule, and the surrounding water medium were accurately modeled in the simulation input files. The standard Y-90 element beta spectrum from ICRU 72 was used, and the physics processes for beta and photon interactions with matters were all included. The dose distribution of this Y-90 disc source was measured in a separate study using Gafchromic EBT-3 films and the results were reported elsewhere. To match the setup of the experiment, a Gafchromic EBT-3 film was also included in the simulation geometry. The simulated dose profiles were exported from the 3D dose distribution results and compared with the measured dose profiles. Transverse dose profiles at different distances from the seed surface were also obtained to study the lateral coverage of the source. RESULTS The measured percent depth dose (PDD) curves along the central axis perpendicular to the surface of the Y-90 disc were constructed from the experimental and simulated data, and normalized to the reference point at 1 mm from the source capsule. Both PDD curves agreed well up to 4 mm from the source surface (maximum difference ± 10%) but deviated from each other beyond 4 mm. The deviation might be caused by the increased measurement uncertainty in the low-dose region. The dose rate at the reference point calculated from the Monte Carlo simulation was 1.09 cGy/mCi-s and agreed very well with the measured dose rate of 1.05 cGy/mCi-s. If the 80% isodose line is selected as the lateral coverage, the lateral dose coverage is maximal (∼4.5 mm) at the plane next to the source surface, and gradually decreases with the increasing distance, approaching 3.5 mm when the plane is 5 mm from the 6-mm diameter source surface. CONCLUSION Monte Carlo simulations were successfully performed to confirm the measured PDD curve of the novel Y-90 disc source. This simulation work laid a solid foundation for characterizing the full dosimetry parameters of this source for episcleral brachytherapy applications.
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Affiliation(s)
- Xiangyun Chang
- MS in Medical Physics Program, Department of Physics and AstronomyHofstra UniversityHempsteadNew YorkUSA
- Radiation MedicineNorthwell HealthLake SuccessNew YorkUSA
| | - Lyu Huang
- Radiation MedicineNorthwell HealthLake SuccessNew YorkUSA
| | - Jian Liu
- Radiation OncologyRhode Island HospitalProvidenceRhode IslandUSA
| | - Yijian Cao
- MS in Medical Physics Program, Department of Physics and AstronomyHofstra UniversityHempsteadNew YorkUSA
- Radiation MedicineNorthwell HealthLake SuccessNew YorkUSA
- Radiation MedicineZucker School of Medicine at Hofstra/NorthwellLake SuccessNew YorkUSA
| | - Jenghwa Chang
- MS in Medical Physics Program, Department of Physics and AstronomyHofstra UniversityHempsteadNew YorkUSA
- Radiation MedicineNorthwell HealthLake SuccessNew YorkUSA
- Radiation MedicineZucker School of Medicine at Hofstra/NorthwellLake SuccessNew YorkUSA
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Pacheco-Callirgos GE, García-Alvarez C, Garcia-Onrubia L, Miguel-Pérez D, Alonso-Martinez P, Diezhandino P, de Frutos Barajas JM, Saornil-Alvarez MA. Brachytherapy in the prevention of recurrence of conjunctival melanoma : Results of a case report in a University Hospital in Valladolid, Spain. Strahlenther Onkol 2023; 199:1025-1030. [PMID: 37280383 DOI: 10.1007/s00066-023-02094-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 04/26/2023] [Indexed: 06/08/2023]
Abstract
AIM Describe the results of brachytherapy in the prevention of recurrences in conjunctival melanoma (CM) and describe a dosimetric protocol. METHODS Retrospective and descriptive case report. Eleven consecutive patients with a confirmed histopathological diagnosis of CM treated with brachytherapy between 1992 and 2023 were reviewed. Demographic, clinical, and dosimetric characteristics as well as recurrences were recorded. Quantitative variables were represented by the mean, median, and standard deviation, and qualitative variables by frequency of distribution. RESULTS Of a total of 27 patients diagnosed with CM, 11 who were treated with brachytherapy were included in the study (7 female; mean age at time of treatment: 59.4 years). Mean follow-up was 58.82 months (range 11-141 months). Of a total of 11 patients, 8 were treated with ruthenium-106 and 3 with iodine-125. Brachytherapy was performed in 6 patients as adjuvant therapy after biopsy-proven CM on histopathology and in the other 5 patients after recurrence. The mean dose was 85 Gy in all cases. Recurrences outside of the previously irradiated area were observed in 3 patients, metastases were diagnosed in 2 patients, and one case of an ocular adverse event was reported. CONCLUSION Brachytherapy is an adjuvant treatment option in invasive conjunctival melanoma. In our case report, only one patient had an adverse effect. However, this topic requires further research. Furthermore, each case is unique and should be evaluated by experts in a multidisciplinary approach involving ophthalmologists, radiation oncologists, and physicists.
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Affiliation(s)
- Gabriela Estefanía Pacheco-Callirgos
- Ocular Oncology Unit, Ophthalmology Department, Hospital Clínico Universitario de Valladolid, Avenida Ramón y Cajal 3, 47003, Valladolid, Spain.
| | - Ciro García-Alvarez
- Ocular Oncology Unit, Ophthalmology Department, Hospital Clínico Universitario de Valladolid, Avenida Ramón y Cajal 3, 47003, Valladolid, Spain
| | - Luis Garcia-Onrubia
- Ocular Oncology Unit, Ophthalmology Department, Hospital Clínico Universitario de Valladolid, Avenida Ramón y Cajal 3, 47003, Valladolid, Spain
| | - David Miguel-Pérez
- Oncology Radiotherapy Department, Hospital Clínico Universitario de Valladolid, 47003, Valladolid, Spain
| | - Pilar Alonso-Martinez
- Oncology Radiotherapy Department, Hospital Clínico Universitario de Valladolid, 47003, Valladolid, Spain
| | - Patricia Diezhandino
- Oncology Radiotherapy Department, Hospital Clínico Universitario de Valladolid, 47003, Valladolid, Spain
| | | | - Maria Antonia Saornil-Alvarez
- Ocular Oncology Unit, Ophthalmology Department, Hospital Clínico Universitario de Valladolid, Avenida Ramón y Cajal 3, 47003, Valladolid, Spain
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10
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Jaarsma-Coes MG, Klaassen L, Marinkovic M, Luyten GPM, Vu THK, Ferreira TA, Beenakker JWM. Magnetic Resonance Imaging in the Clinical Care for Uveal Melanoma Patients-A Systematic Review from an Ophthalmic Perspective. Cancers (Basel) 2023; 15:cancers15112995. [PMID: 37296958 DOI: 10.3390/cancers15112995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/24/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
Conversely to most tumour types, magnetic resonance imaging (MRI) was rarely used for eye tumours. As recent technical advances have increased ocular MRI's diagnostic value, various clinical applications have been proposed. This systematic review provides an overview of the current status of MRI in the clinical care of uveal melanoma (UM) patients, the most common eye tumour in adults. In total, 158 articles were included. Two- and three-dimensional anatomical scans and functional scans, which assess the tumour micro-biology, can be obtained in routine clinical setting. The radiological characteristics of the most common intra-ocular masses have been described extensively, enabling MRI to contribute to diagnoses. Additionally, MRI's ability to non-invasively probe the tissue's biological properties enables early detection of therapy response and potentially differentiates between high- and low-risk UM. MRI-based tumour dimensions are generally in agreement with conventional ultrasound (median absolute difference 0.5 mm), but MRI is considered more accurate in a subgroup of anteriorly located tumours. Although multiple studies propose that MRI's 3D tumour visualisation can improve therapy planning, an evaluation of its clinical benefit is lacking. In conclusion, MRI is a complementary imaging modality for UM of which the clinical benefit has been shown by multiple studies.
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Affiliation(s)
- Myriam G Jaarsma-Coes
- Department of Ophthalmology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
- Department of Radiology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Lisa Klaassen
- Department of Ophthalmology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
- Department of Radiology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
- Department of Radiation Oncology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Marina Marinkovic
- Department of Ophthalmology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Gregorius P M Luyten
- Department of Ophthalmology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - T H Khanh Vu
- Department of Ophthalmology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Teresa A Ferreira
- Department of Radiology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Jan-Willem M Beenakker
- Department of Ophthalmology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
- Department of Radiology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
- Department of Radiation Oncology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
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11
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Trofimov AV, Aronow ME, Gragoudas ES, Keane FK, Kim IK, Shih HA, Bhagwat MS. A Systematic Comparison of Dose Distributions Delivered in 125I Plaque Brachytherapy and Proton Radiation Therapy for Ocular Melanoma. Int J Radiat Oncol Biol Phys 2023; 115:501-510. [PMID: 35878716 DOI: 10.1016/j.ijrobp.2022.07.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 07/06/2022] [Accepted: 07/13/2022] [Indexed: 01/11/2023]
Abstract
PURPOSE To characterize dose distributions with 125I plaque brachytherapy compared with proton radiation therapy for ocular melanoma for relevant clinical scenarios, based on tumor base diameter (d), apical height (h), and location. METHODS AND MATERIALS Plaque and proton treatment plans were created for 4 groups of cases: (1) REF: 39 instances of reference midsize circular-base tumor (d = 12 mm, h = 5 mm), in locations varying by retinal clock hours and distance to fovea, optic disc, and corneal limbus; (2) SUP: 25 superiorly located; (3) TEMP: 25 temporal; and (4) NAS: 25 nasally located tumors that were a fixed distance from the fovea but varying in d (6-18 mm) and h (3-11 mm). For both modalities, 111 unique scenarios were characterized in terms of the distance to points of interest, doses delivered to fovea, optic disc, optic nerve at 3 mm posterior to the disc (ON@3mm), lens, and retina. Comparative statistical evaluation was performed with the Mann-Whitney U test. RESULTS Superior dose distributions favored plaque for sparing of (1) fovea in large (d + h ≥ 21 mm) NAS tumors; (2) ON@3mm in REF cases located ≤4 disc diameters from disc, and in NAS overall. Protons achieved superior dose sparing of (1) fovea and optic disc in REF, SUP, and TEMP; (2) ON@3mm in REF >4 disc diameters from disc, and in SUP and TEMP; and (3) the lens center overall and lens periphery in REF ≤6 mm from the corneal limbus, and in TEMP with h = 3 mm. Although protons could completely spare sections of the retina, plaque dose was more target conformal in the high-dose range (50% and 90% of prescription dose). CONCLUSIONS Although comparison between plaque and proton therapy is not straightforward because of the disparity in dose rate, prescriptions, applicators, and delivery techniques, it is possible to identify distinctions between dose distributions, which could help inform decisions by providers and patients.
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Affiliation(s)
- Alexei V Trofimov
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
| | - Mary E Aronow
- Ocular Melanoma Center, Retina Service, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Evangelos S Gragoudas
- Ocular Melanoma Center, Retina Service, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Florence K Keane
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Ivana K Kim
- Ocular Melanoma Center, Retina Service, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Helen A Shih
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Mandar S Bhagwat
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
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12
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Poder J, Rivard MJ, Howie A, Carlsson Tedgren Å, Haworth A. Risk and Quality in Brachytherapy From a Technical Perspective. Clin Oncol (R Coll Radiol) 2023:S0936-6555(23)00002-X. [PMID: 36682968 DOI: 10.1016/j.clon.2023.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/23/2022] [Accepted: 01/04/2023] [Indexed: 01/15/2023]
Abstract
AIMS To provide an overview of the history of incidents in brachytherapy and to describe the pillars in place to ensure that medical physicists deliver high-quality brachytherapy. MATERIALS AND METHODS A review of the literature was carried out to identify reported incidents in brachytherapy, together with an evaluation of the structures and processes in place to ensure that medical physicists deliver high-quality brachytherapy. In particular, the role of education and training, the use of process and technical quality assurance and the role of international guidelines are discussed. RESULTS There are many human factors in brachytherapy procedures that introduce additional risks into the process. Most of the reported incidents in the literature are related to human factors. Brachytherapy-related education and training initiatives are in place at the societal and departmental level for medical physicists. Additionally, medical physicists have developed process and technical quality assurance procedures, together with international guidelines and protocols. Education and training initiatives, together with quality assurance procedures and international guidelines may reduce the risk of human factors in brachytherapy. CONCLUSION Through application of the three pillars (education and training; process control and technical quality assurance; international guidelines), medical physicists will continue to minimise risk and deliver high-quality brachytherapy treatments.
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Affiliation(s)
- J Poder
- Department of Radiation Oncology, St George Cancer Care Centre, Kogarah, New South Wales, Australia; School of Physics, University of Sydney, Camperdown, New South Wales, Australia; Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales, Australia.
| | - M J Rivard
- Department of Radiation Oncology, Alpert Medical School of Brown University, Providence, RI, USA
| | - A Howie
- Department of Radiation Oncology, St George Cancer Care Centre, Kogarah, New South Wales, Australia
| | - Å Carlsson Tedgren
- Department of Health, Medicine and Caring Sciences (HMV), Radiation Physics, Linköping University, Linköping, Sweden; Medical Radiation Physics and Nuclear Medicine, The Karolinska University Hospital, Stockholm, Sweden; Department of Oncology Pathology, The Karolinska Institute, Stockholm, Sweden
| | - A Haworth
- School of Physics, University of Sydney, Camperdown, New South Wales, Australia
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13
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Meltsner SG, Rodrigues A, Materin MA, Kirsch DG, Craciunescu O. Transitioning from a COMS-based plaque brachytherapy program to using eye physics plaques and plaque simulator treatment planning system: A single institutional experience. J Appl Clin Med Phys 2023; 24:e13902. [PMID: 36637797 PMCID: PMC10161060 DOI: 10.1002/acm2.13902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 11/08/2022] [Accepted: 12/15/2022] [Indexed: 01/14/2023] Open
Abstract
The aim of this work is to describe the implementation and commissioning of a plaque brachytherapy program using Eye Physics eye plaques and Plaque Simulator treatment planning system based on the experience of one institution with an established COMS-based plaque program. Although commissioning recommendations are available in official task groups publications such as TG-129 and TG-221, we found that there was a lack of published experiences with the specific details of such a transition and the practical application of the commissioning guidelines. The specific issues addressed in this paper include discussing the lack of FDA approval of the Eye Physics plaques and Plaque Simulator treatment planning system, the commissioning of the plaques and treatment planning system including considerations of the heterogeneity corrected calculations, and the implementation of a second check using an FDA-approved treatment planning system. We have also discussed the use of rental plaques, the analysis of plans using dose histograms, and the development of a quality management program. By sharing our experiences with the commissioning of this program this document will assist other institutions with the same task and act as a supplement to the recommendations in the recently published TG-221.
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Affiliation(s)
- Sheridan G Meltsner
- Department of Radiation Oncology, Duke University, Durham, North Carolina, USA
| | - Anna Rodrigues
- Department of Radiation Oncology, Duke University, Durham, North Carolina, USA
| | - Miguel A Materin
- Departments of Ophthalmology, Duke University, Durham, North Carolina, USA
| | - David G Kirsch
- Department of Radiation Oncology, Duke University, Durham, North Carolina, USA
| | - Oana Craciunescu
- Department of Radiation Oncology, Duke University, Durham, North Carolina, USA
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14
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Fernandes AG, Tavares JHC, Branco AMC, Morales MC, Belfort Neto R. Choroidal melanoma tumor profile and treatment pattern for newly diagnosed patients at a reference public hospital in Sao Paulo, Brazil. BMC Ophthalmol 2022; 22:511. [PMID: 36578013 PMCID: PMC9798647 DOI: 10.1186/s12886-022-02742-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 12/16/2022] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Choroid, ciliary body, and iris melanomas are often grouped as uveal melanoma, the most common intraocular primary malignancy. The purpose of the current study was to analyze the tumor profile of newly diagnosed cases of choroidal melanoma at a reference center in Sao Paulo, Brazil, and to investigate the frequency of eyes treated by enucleation that could have been treated with brachytherapy if available in the service. METHODS Medical records of patients referred to our service with initial diagnostic hypothesis of choroidal melanoma from July 2014 to June 2020 were analysed on demographics, diagnosis confirmation, tumor measurement by ultrasonography and established treatment. Data were evaluated on clinical and demographic characteristics as age, sex, affected eye, ultrasound parameters, and treatment management of patients with clinically diagnosed choroidal melanoma. Among the patients submitted to enucleation, we investigated how many could have been selected to receive brachytherapy. RESULTS From the 102 patients referred with the choroidal melanoma diagnosis hypothesis, 70 (68.62%) were confirmed. Mean measurements from the tumors in millimetres were: 9.19 ± 3.69 at height and 12.97 ± 3.09 by 13.30 ± 3.30 at basal. A total of 48 cases (68.57%) were enucleated, 8 (11.43%) were treated by brachytherapy in a different service, and 14 patients (20.00%) returned for enucleation at their original referral center. Out of the 48 patients enucleated, 26 (54.17%) could have been selected to brachytherapy treatment. CONCLUSIONS The results indicate a late diagnosis of choroidal melanoma cases referred to our service. Most enucleated cases could have been treated with brachytherapy if it was broadly available at the national public health insurance. Further public health political efforts should focus on early diagnosis and better quality of life post-treatment for oncologic patients.
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Affiliation(s)
- Arthur Gustavo Fernandes
- grid.411249.b0000 0001 0514 7202Departament of Ophthalmology and Visual Sciences, Escola Paulista de Medicina, Universidade Federal de São Paulo – UNIFESP, Rua Botucatu, 816, 04023-062, SP Sao Paulo, Brazil ,grid.22072.350000 0004 1936 7697Department of Anthropology and Archaeology, University of Calgary, Calgary, AB Canada
| | - Jorge Henrique Cavalcante Tavares
- grid.411249.b0000 0001 0514 7202Departament of Ophthalmology and Visual Sciences, Escola Paulista de Medicina, Universidade Federal de São Paulo – UNIFESP, Rua Botucatu, 816, 04023-062, SP Sao Paulo, Brazil
| | - Ana Marisa Castello Branco
- grid.411249.b0000 0001 0514 7202Departament of Ophthalmology and Visual Sciences, Escola Paulista de Medicina, Universidade Federal de São Paulo – UNIFESP, Rua Botucatu, 816, 04023-062, SP Sao Paulo, Brazil
| | - Melina Correa Morales
- grid.411249.b0000 0001 0514 7202Departament of Ophthalmology and Visual Sciences, Escola Paulista de Medicina, Universidade Federal de São Paulo – UNIFESP, Rua Botucatu, 816, 04023-062, SP Sao Paulo, Brazil
| | - Rubens Belfort Neto
- grid.411249.b0000 0001 0514 7202Departament of Ophthalmology and Visual Sciences, Escola Paulista de Medicina, Universidade Federal de São Paulo – UNIFESP, Rua Botucatu, 816, 04023-062, SP Sao Paulo, Brazil
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15
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Liakopoulos DA, Perisinakis K, Solomou G, Kouvidakis A, Drakonaki EE, Bontzos G, Papadaki E, Detorakis ET. Individualized dosimetry in Ru-106 ophthalmic brachytherapy based on MRI-derived ocular anatomical parameters. Brachytherapy 2022; 21:904-911. [PMID: 35995724 DOI: 10.1016/j.brachy.2022.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 06/01/2022] [Accepted: 07/01/2022] [Indexed: 12/14/2022]
Abstract
PURPOSE To estimate ocular geometry-related inaccuracies of the dosimetric plan in Ru-106 ophthalmic brachytherapy. METHODS AND MATERIALS Thirty patients with intraocular lesions were treated with brachytherapy using a Ru-106 plaque-shell of inner radius of 12 mm. Magnetic resonance imaging was employed to determine the external scleral radius at tumor site and the tumor margins. A mathematical model was developed to determine the distance between the external sclera and the internal surface of the plaque associated with the tangential application of the plaque on the treated eye. Differences in delivered dose to the tumor apex, sclera and tumor margins as derived by considering the default eye-globe of standard size (external sclera radius = 12 mm) against the individual-specific eye globe were determined. RESULTS The radius of external sclera at the tumor site was found to range between 10.90 and 13.05 mm for the patient cohort studied. When the patient specific eye-globe/tumor geometry is not taken into account, the delivered dose was found to be overestimated by 8.1% ± 4.1% (max = 15.3%) at tumor apex, by 1.5% ± 2.8% (max = 5.7%) at anterior tumor margin, by 16.6% ± 7.5% (max = 36.4%) at posterior tumor margin and 8.1% ± 3.8% (max = 13.2%) at central sclera of eyes with lower than the default radius. The corresponding dose overestimations for eyes with higher than the default radius was 13.5% ± 4.3% (max = 22.3%), 1.5% ± 2.8% (max = 5.7%), 12.6% ± 4.5% (max = 20.0%), and 15.1% ± 5.0% (max = 24.4%). CONCLUSIONS The proposed patient-specific approach for Ru-106 brachytherapy treatment planning may improve dosimetric accuracy. Individualized treatment planning dosimetry may prevent undertreatment of intraocular tumors especially for highly myopic or hyperopic eyes.
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Affiliation(s)
| | - Kostas Perisinakis
- Department of Medical Physics, University of Crete, Medical School, Heraklion, Crete, Greece; Computational BioMedicine Laboratory (CBML), Foundation for Research and Technology-Hellas (FORTH), Heraklion, Greece
| | - Georgia Solomou
- Department of Medical Physics, University of Crete, Medical School, Heraklion, Crete, Greece
| | | | | | | | - Efrosini Papadaki
- Department of Radiology, University Hospital of Heraklion, Crete, Greece
| | - Efstathios T Detorakis
- Department of Ophthalmology, Medical School, University of Crete, Heraklion, Crete, Greece
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16
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Oare C, Sun S, Dusenbery K, Reynolds M, Koozekanani D, Gerbi B, Ferreira C. Analysis of dose to the macula, optic disc, and lens in relation to vision toxicities - A retrospective study using COMS eye plaques. Phys Med 2022; 101:71-78. [PMID: 35981450 DOI: 10.1016/j.ejmp.2022.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 07/08/2022] [Accepted: 08/03/2022] [Indexed: 11/28/2022] Open
Abstract
PURPOSE The aim of this study was to relate common toxicity endpoints with dose to the macula, optic disc, and lens for uveal melanoma patients treated with Iodine-125 Collaborative Ocular Melanoma Study (COMS) eye plaque brachytherapy. METHODS A cohort of 52 patients treated at a single institution between 2005 and 2019 were retrospectively reviewed. Demographics, dosimetry, and clinical outcomes were recorded. Univariate, relative risk, and Kaplan-Meier analyses were performed to relate dose to toxicity endpoints including retinopathy, vision decline, and cataracts. RESULTS By the end of follow up (Median = 3.6 years, Range = 0.4 - 13.5 years), 65 % of eyes sustained radiation retinopathy, 40 % demonstrated moderate vision decline (>5 Snellen lines lost), and 56 % developed cataracts. Significant (p < 0.05) risk estimates exist for retinopathy and VA decline for doses >52 Gy to the macula and >42 Gy to the optic disc. Moreover, dose to the lens > 16 Gy showed a significant risk for cataract formation. Kaplan-Meier analysis demonstrated significantly different incidence of radiation retinopathy for > 52 Gy to the macula and > 42 Gy to the optic disc. In addition, the Kaplan-Meier analysis showed significantly different incidence of cataract formation for patients with lens dose > 16 Gy. CONCLUSIONS Dose-effect relationships exist for the macula and optic disc with respect to the loss of visual acuity and the development of retinopathy. To better preserve vision after treatment, further research is needed to reduce macula, optic disc, and lens doses while maintaining tumor control.
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Affiliation(s)
- Courtney Oare
- University of Minnesota Medical School, 420 Delaware St SE, MMC 494, Minneapolis, MN 55455, United States.
| | - Susan Sun
- University of Minnesota Medical School, 420 Delaware St SE, MMC 494, Minneapolis, MN 55455, United States
| | - Kathryn Dusenbery
- University of Minnesota Medical School, 420 Delaware St SE, MMC 494, Minneapolis, MN 55455, United States
| | - Margaret Reynolds
- University of Minnesota Medical School, 420 Delaware St SE, MMC 494, Minneapolis, MN 55455, United States
| | - Dara Koozekanani
- University of Minnesota Medical School, 420 Delaware St SE, MMC 494, Minneapolis, MN 55455, United States
| | - Bruce Gerbi
- University of Minnesota Medical School, 420 Delaware St SE, MMC 494, Minneapolis, MN 55455, United States
| | - Clara Ferreira
- University of Minnesota Medical School, 420 Delaware St SE, MMC 494, Minneapolis, MN 55455, United States
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17
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Modified Geometry of 106Ru Asymmetric Eye Plaques to Improve Dosimetric Calculations in Ophthalmic Brachytherapy. J Pers Med 2022; 12:jpm12050723. [PMID: 35629144 PMCID: PMC9144752 DOI: 10.3390/jpm12050723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/22/2022] [Accepted: 04/27/2022] [Indexed: 11/29/2022] Open
Abstract
Ru/Rh asymmetric plaques for ophthalmic brachytherapy have special geometric designs with a cutout intended to prevent irradiation of critical ocular structures proximal to the tumor. In this work, we present new geometric models for PENELOPE+PenEasy Monte Carlo simulations of these applicators, differing from the vendor-reported geometry, that better match their real geometry to assess their dosimetric impact. Simulation results were benchmarked to experimental dosimetric data from radiochromic film measurements, data provided by the manufacturer in the calibration certificates, and other experimental results published in the literature, obtaining, in all cases, better agreement with the modified geometries. The clinical impact of the new geometric models was evaluated by simulating real clinical cases using patient-specific eye models. The cases calculated using the modified geometries presented higher doses to the critical structures proximal to the cutout region. The modified geometric models presented in this work provide a more accurate representation of the asymmetric plaques, greatly improving the agreement between Monte Carlo calculations and experimental measurements. Lack of consideration of accurate geometric models has been shown to be translated into notable increases in dose to organs at risk in clinical cases.
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18
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Nakamura S, Murakami N, Suzuki S, Ito K, Takemori M, Nakayama H, Kaga K, Chiba T, Iijima K, Takahashi K, Goka T, Itami J, Okamoto H, Igaki H. Monte Carlo simulation of tilted contact plaque brachytherapy placement for juxtapapillary retinoblastoma. Radiat Oncol 2022; 17:16. [PMID: 35073956 PMCID: PMC8785594 DOI: 10.1186/s13014-022-01986-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 01/10/2022] [Indexed: 11/24/2022] Open
Abstract
Background The 106-Ruthenium contact plaque applicator is utilized for the treatment of intraocular tumor within a thickness of less than 6 mm. If anything obstructs the placement of the plaque applicator, the treatment is generally difficult because the applicator has to be temporarily located just on the opposite side of the retinal tumor. Furthermore, the plaque applicator edge of approximately 1 mm does not contain 106Ru, estimating the delivered radiation dose for eccentric tumor is challenging because the lateral dose profile is inadequately provided by the manufacture’s certification. This study aims to simulate tumor coverage of the tilted applicator placement for treating an infant with juxtapapillary retinoblastoma and to achieve the effective treatment. Case presentation We present an infant with retinoblastoma whose tumor involved macular and was invading just temporal side of the optic disc. Additionally, posterior staphyloma was induced by a series of previous treatments, making it more difficult to treat the standard plaque placement. Thus, the applicator type of CCA was intentionally tilted to the eyeball and the distance between the posterior edge of the applicator and the eyeball had to be then equal to or more than 2 mm based on the dose distribution of the applicator calculated using Monte Carlo simulation to minimize damage to surrounding tissues while covering the tumor. It was then comparable to the certification and previous reports. Based on the acquired dose distribution, the optimal placement of the applicator was derived from varying the distance between the applicator’s edge and the eyeball, and the distance was then determined to be 2 mm. In this case, the minimum dose rate in the tumor was 25.5 mGy/min, and the time required to deliver the prescribed dose was 26.2 h. Therefore, the tilted 106Ru plaque applicator placement could deliver the required dose for the treatment. The physical examination revealed no active tumor as a result of the treatment. Conclusions Optimizing the placement of the 106Ru plaque applicator, it was possible to guarantee that the prescribed dose will be delivered to the tumor even if the standard placement is not possible for the juxtapapillary tumor.
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19
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Buonanno F, Conson M, de Almeida Ribeiro C, Oliviero C, Itta F, Liuzzi R, Pacelli R, Cella L, Clemente S. Local tumor control and treatment related toxicity after plaque brachytherapy for uveal melanoma: A systematic review and a data pooled analysis. Radiother Oncol 2021; 166:15-25. [PMID: 34774654 DOI: 10.1016/j.radonc.2021.11.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/29/2021] [Accepted: 11/02/2021] [Indexed: 01/02/2023]
Abstract
Uveal melanoma (UM) represents the most common primary intraocular tumor, and nowadays eye plaque brachytherapy (EPB) is the most frequently used visual acuity preservation treatment option for small to medium sized UMs. The excellent local tumor control (LTC) rate achieved by EPB may be associated with severe complications and adverse events. Several dosimetric and clinical risk factors for the development of EPB-related ocular morbidity can be identified. However, morbidity predictive models specifically developed for EPB are still scarce. PRISMA methodology was used for the present systematic review of articles indexed in PubMed in the last sixteen years on EPB treatment of UM which aims at determining the major factors affecting local tumor control and ocular morbidities. To our knowledge, for the first time in EPB field, local tumor control probability (TCP) and normal tissue complication probability (NTCP) modelling on pooled clinical outcomes were performed. The analyzed literature (103 studies including 21,263 UM patients) pointed out that Ru-106 EPB provided high local control outcomes while minimizing radiation induced complications. The use of treatment planning systems (TPS) was the most influencing factor for EPB outcomes such as metastasis occurrence, enucleation, and disease specific survival, irrespective of radioactive implant type. TCP and NTCP parameters were successfully extracted for 5-year LTC, cataract and optic neuropathy. In future studies, more consistent recordings of ocular morbidities along with accurate estimation of doses through routine use of TPS are needed to expand and improve the robustness of toxicity risk prediction in EPB.
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Affiliation(s)
- Francesca Buonanno
- University Federico II, Post Graduate School in Medical Physics, Department of Advanced Biomedical Sciences, Napoli, Italy
| | - Manuel Conson
- University Federico II, Department of Advanced Biomedical Sciences, Napoli, Italy
| | | | - Caterina Oliviero
- University Hospital Federico II, Unit of Medical Physics and Radioprotection, Napoli, Italy
| | - Francesca Itta
- University Federico II, Post Graduate School in Medical Physics, Department of Advanced Biomedical Sciences, Napoli, Italy
| | - Raffaele Liuzzi
- National Research Council (CNR), Institute of Biostructures and Bioimaging, Napoli, Italy
| | - Roberto Pacelli
- University Federico II, Department of Advanced Biomedical Sciences, Napoli, Italy
| | - Laura Cella
- National Research Council (CNR), Institute of Biostructures and Bioimaging, Napoli, Italy.
| | - Stefania Clemente
- University Hospital Federico II, Unit of Medical Physics and Radioprotection, Napoli, Italy
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Shah C, Vicini F, Beriwal S, Thaker N, Frank SJ, Rossi P, Orio P, Chang AJ, Joshi N, Campbell SR, Naghavi A, Chao S, Kamrava M, Deufel CL, Mourtada F, Suh JH. American brachytherapy society radiation oncology alternative payment model task force: Quality measures and metrics for brachytherapy. Brachytherapy 2021; 21:63-74. [PMID: 34732290 DOI: 10.1016/j.brachy.2021.10.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 09/26/2021] [Accepted: 10/05/2021] [Indexed: 12/21/2022]
Abstract
PURPOSE Brachytherapy is an essential technique to deliver radiation therapy and is involved in the treatment of multiple disease sites as monotherapy or as an adjunct to external beam radiation therapy. With a growing focus on the cost and value of cancer treatments as well new payment models, it is essential that standardized quality measures and metrics exist to allow for straightforward assessment of brachytherapy quality and for the development of clinically significant and relevant clinical data elements. We present the American Brachytherapy Society consensus statement on quality measures and metrics for brachytherapy as well as suggested clinical data elements. METHODS AND MATERIALS Members of the American Brachytherapy Society with expertise in disease site specific brachytherapy created a consensus statement based on a literature review and clinical experience. RESULTS Key quality measures (ex. workup, clinical indications), dosimetric metrics, and clinical data elements for brachytherapy were evaluated for each modality including breast cancer, cervical cancer, endometrial cancer, prostate cancer, keratinocyte carcinoma, soft tissue sarcoma, and uveal melanoma. CONCLUSIONS This consensus statement provides standardized quality measures and dosimetric quality metrics as well as clinical data elements for each disease site to allow for standardized assessments of brachytherapy quality. Moving forward, a similar paradigm can be considered for external beam radiation therapy as well, providing comprehensive radiation therapy quality measures, metrics, and clinical data elements that can be incorporated into new payment models.
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Affiliation(s)
- Chirag Shah
- Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH.
| | | | - Sushil Beriwal
- Department of Radiation Oncology, UPMC Hillman cancer Center, Pittsburgh, PA
| | - Nikhil Thaker
- Division of Radiation Oncology, Arizona Oncology, Tucson, AZ
| | - Steven J Frank
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX
| | | | - Peter Orio
- Department of Radiation Oncology, Dana Farber Cancer Institute, Boston, MA
| | - Albert J Chang
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA
| | - Nikhil Joshi
- Department of Radiation Oncology, Rush University, Chicago, IL
| | - Shauna R Campbell
- Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH
| | - Arash Naghavi
- Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL
| | - Samuel Chao
- Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH
| | - Mitchell Kamrava
- Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, CA
| | | | - Firas Mourtada
- Department of Radiation Oncology, Helen F. Graham Cancer Center, ChristianaCare, Newark, DE
| | - John H Suh
- Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH
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Bakshi AK, Shrivastava V, Chattaraj A, Samuel K, Palani Selvam T, Sapra BK, Sinharoy P, Banerjee D, Sugilala G, Manohar S, Kaushik CP. Surface dose rate variations in planar and curved geometries of 106Ru/ 106Rh plaque sources for ocular tumors. Phys Med 2021; 89:200-209. [PMID: 34399207 DOI: 10.1016/j.ejmp.2021.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 07/31/2021] [Accepted: 08/02/2021] [Indexed: 11/19/2022] Open
Abstract
PURPOSE Investigation of surface dose rate variation with respect to the source configuration of 106Ru/106Rh eye plaque. To explore an alternate way to determine activity of brachytherapy plaques. METHODS The surface dose rates of 106Ru/106Rh plaque developed indigenously were measured by extrapolation chamber. To rule out possibility of any error in the activity distribution and quantity, same source was used in two different configurations namely planar and curved. EBT3 Gafchromic film was used for determination of uniformity in activity. Monte Carlo-based Codes EGSnrc and FLUKA were used to calculate dose rate in tissue, percentage depth dose and for determination of activity. Parameters and correction factors were estimated using simulations. RESULTS The measured reference absorbed dose rates for planar and curved 106Ru/106Rh eye plaques are found to be 589 ± 29 mGy/h and 560 ± 28 mGy/h, respectively. The difference in the reference absorbed dose rate of curved eye plaque is about ~5% as compared to planar configuration. The FLUKA-calculated dose values are almost independent of cavity length of the extrapolation chamber for both eye plaques. The FLUKA-based dose rates per μCi 106Ru/106Rh are about 17.28 ± 0.08 mGy/h and 16.48 ± 0.06 mGy/h, respectively for planar and curved eye plaques which match well with the measurements. The calculated activities for planar and curved eye plaques are 34.08 μCi and 33.98 μCi, respectively. CONCLUSIONS Surface dose rates for a prototype 106Ru/106Rh eye plaque with different configurations were estimated using simulations and measured experimentally. An alternate way to determine activity of beta-gamma brachytherapy plaque has been proposed.
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Affiliation(s)
- A K Bakshi
- Radiological Physics & Advisory Division, India; Homi Bhabha National Institute, Mumbai 400 094, India.
| | | | | | | | - T Palani Selvam
- Radiological Physics & Advisory Division, India; Homi Bhabha National Institute, Mumbai 400 094, India
| | - B K Sapra
- Radiological Physics & Advisory Division, India; Homi Bhabha National Institute, Mumbai 400 094, India
| | - Prithwish Sinharoy
- Nuclear Recycle Group, Bhabha Atomic Research Centre, Mumbai 400 085, India; Homi Bhabha National Institute, Mumbai 400 094, India
| | - Dayamoy Banerjee
- Nuclear Recycle Group, Bhabha Atomic Research Centre, Mumbai 400 085, India; Homi Bhabha National Institute, Mumbai 400 094, India
| | - G Sugilala
- Nuclear Recycle Group, Bhabha Atomic Research Centre, Mumbai 400 085, India; Homi Bhabha National Institute, Mumbai 400 094, India
| | - Smitha Manohar
- Radiological Physics & Advisory Division, India; Nuclear Recycle Group, Bhabha Atomic Research Centre, Mumbai 400 085, India; Homi Bhabha National Institute, Mumbai 400 094, India
| | - C P Kaushik
- Nuclear Recycle Group, Bhabha Atomic Research Centre, Mumbai 400 085, India; Homi Bhabha National Institute, Mumbai 400 094, India
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Miras Del Río H, Ortiz Lora A, Bertolet Reina A, Terrón León JA. A Monte Carlo dose calculation system for ophthalmic brachytherapy based on a realistic eye model. Med Phys 2021; 48:4542-4559. [PMID: 34250607 DOI: 10.1002/mp.15045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 05/11/2021] [Accepted: 06/03/2021] [Indexed: 01/13/2023] Open
Abstract
PURPOSE There is a growing trend towards the adoption of model-based calculation algorithms (MBDCAs) for brachytherapy dose calculations which can properly handle media and source/applicator heterogeneities. However, most of dose calculations in ocular plaque therapy are based on homogeneous water media and standard in-silico ocular phantoms, ignoring non-water equivalency of the anatomic tissues and heterogeneities in applicators and patient anatomy. In this work, we introduce EyeMC, a Monte Carlo (MC) model-based calculation algorithm for ophthalmic plaque brachytherapy using realistic and adaptable patient-specific eye geometries and materials. METHODS We used the MC code PENELOPE in EyeMC to model Bebig IsoSeed I25.S16 seeds in COMS plaques and 106 Ru/106 Rh applicators that are coupled onto a customizable eye model with realistic geometry and composition. To significantly reduce calculation times, we integrated EyeMC with CloudMC, a cloud computing platform for radiation therapy calculations. EyeMC is equipped with an evaluation module that allows the generation of isodose distributions, dose-volume histograms, and comparisons with Plaque Simulator three-dimensional dose distribution. We selected a sample of patients treated with 125 I and 106 Ru isotopes in our institution, covering a variety of different type of plaques, tumor sizes, and locations. Results from EyeMC were compared to the original plan calculated by the TPS Plaque Simulation, studying the influence of heterogeneous media composition as well. RESULTS EyeMC calculations for Ru plaques agreed well with manufacturer's reference data and data of MC simulations from Hermida et al. (2013). Significant deviations, up to 20%, were only found in lateral profiles for notched plaques. As expected, media composition significantly affected estimated doses to different eye structures, especially in the 125 I cases evaluated. Dose to sclera and lens were found to be about 12% lower when considering real media, while average dose to tumor was 9% higher. 106 Ru cases presented a 1%-3% dose reduction in all structures using real media for calculation, except for the lens, which showed an average dose 7.6% lower than water-based calculations. Comparisons with Plaque Simulator calculations showed large differences in dose to critical structures for 106 Ru notched plaques. 125 I cases presented significant and systematic dose deviations when using the default calculation parameters from Plaque Simulator version 5.3.8., which were corrected when using calculation parameters from a custom physics model for carrier-attenuation and air-interface correction functions. CONCLUSIONS EyeMC is a MC calculation system for ophthalmic brachytherapy based on a realistic and customizable eye-tumor model which includes the main eye structures with their real composition. Integrating this tool into a cloud computing environment allows to perform high-precision MC calculations of ocular plaque treatments in short times. The observed variability in eye anatomy among the selected cases justifies the use of patient-specific models.
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Affiliation(s)
- Héctor Miras Del Río
- Department of Medical Physics, Hospital Universitario Virgen Macarena, Seville, Spain
| | - Antonio Ortiz Lora
- Department of Medical Physics, Hospital Universitario Virgen Macarena, Seville, Spain
| | - Alejandro Bertolet Reina
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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23
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Oare CC, Deufel CL, McCauley Cutsinger J, De La Fuente Herman T, Ferreira C. On the importance of quality assurance (QA) for COMS eye plaque Silastic inserts: A guide to measurement methods, typical variations, and an example of how QA intercepted a manufacturing aberration. J Appl Clin Med Phys 2021; 22:72-82. [PMID: 34231949 PMCID: PMC8364280 DOI: 10.1002/acm2.13325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/22/2021] [Accepted: 05/26/2021] [Indexed: 12/15/2022] Open
Abstract
PURPOSE Eye plaques are widely used for ocular melanoma and provide an effective alternative to enucleation with adequate tumor control. A COMS plaque utilizes a Silastic insert for precise positioning of the radioactive seeds with respect to the scleral surface of the eye; however, due to manufacturing variability, the insert may unintentionally increase or decrease the distance between the sources and tumor. The purpose of this work is to provide guidance in measuring and identifying outliers in Silastic inserts. The importance of regular quality assurance (QA) is illustrated in an experience where a systematic problem was detected and the manufacturer's 22-mm mold was corrected. METHODS A detailed description of the molds and manufacturing process used to produce Silastic inserts is provided, including photographs of the process steps. The variability in Silastic insert production was evaluated by measuring the thickness of 124 Silastic inserts. An estimate of how the observed Silastic thickness discrepancies impact the dose to the tumor and critical eye structures was performed using homogeneous dose calculations. A standard QA protocol was developed to guide the clinical user. RESULTS Thickness of the measured Silastic inserts ranged from 1.22 to 2.67 mm, demonstrating variation from the 2.25 mm standard. Six of the 22-mm inserts were outliers (Δthickness >3 standard deviations) and were excluded from the statistics. The outliers were investigated with the help of the manufacturer, who discovered that a systematic error was accidentally introduced into the 22-mm mold. CONCLUSIONS Due to manufacturing errors or variability, the Silastic inserts used in COMS eye plaques may be thicker or thinner than the design standard. Such variations may impact tumor control or increase the risk of normal tissue side effects. A standardized QA program is recommended to detect variations and communicate unusual findings to the manufacturer.
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Affiliation(s)
- Courtney C Oare
- Department of Radiation Oncology, University of Minnesota Medical School, Minneapolis, MN, 55455, USA
| | | | | | - Tania De La Fuente Herman
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA
| | - Clara Ferreira
- Department of Radiation Oncology, University of Minnesota Medical School, Minneapolis, MN, 55455, USA
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Lee YC, Lin SC, Kim Y. Optic Disc Dose Comparison Between 125I and 103Pd Collaborative Ocular Melanoma Study (COMS) Plaques Based on Current Clinical Practice. Cureus 2021; 13:e15980. [PMID: 34336471 PMCID: PMC8317005 DOI: 10.7759/cureus.15980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/27/2021] [Indexed: 11/17/2022] Open
Abstract
Purpose The purpose of this study is to compare optic disc dose (ODD) between 125I and 103Pd Collaborative Ocular Melanoma Study (COMS) plaques in ocular brachytherapy. Methods A previously validated in-house brachytherapy dose calculation program was used for ODD calculations. ODD was calculated as a function of tumor margin-to-optic disc distance (DT) up to 5 mm for various tumor basal dimensions (BDs), for a prescription depth of 5 mm, and for standard and notched COMS plaques loaded with 125I (model: IAI-125A) and 103Pd (model: IAPd-103A) seeds. ODD calculations were repeated for prescription depths from 2 mm to 10 mm in 1 mm intervals. A prescribed dose of 85 Gy (irradiation time: 120 hours) was normalized to each prescription depth. Dose conversion factors (DCFs) for each prescription depth were calculated by taking a ratio of [total reference air kerma (TRAK) per seed]prescription depth to [TRAK per seed]5 mm. ODD reduction by notched COMS plaques was calculated for each prescription depth by subtracting ODD for notched COMS plaques from ODD for standard COMS plaques. Results Trends of ODD as a function of DT for various BDs are similar between the two seed types in both standard and notched COMS plaques. However, due to the energy difference, there exists a transition distance (dt) for each BD in each plaque at which ODD for 125I COMS plaques equals that for 103Pd COMS plaques. For small BDs, at DT <dt, ODD for 103Pd COMS plaques is higher than that for 125I COMS plaques while at DT >dt, the opposite is observed. For the largest 1-3 BD(s), contrarily, dt occurs within the tumor, and thus, ODD for 125I COMS plaquesis always higher. Trends of ODD reduction by notched COMS plaques as a function of DT for various BDs are the same for the two seed types except that maximum ODD reduction by 103Pd COMS notched plaques is larger. DCF increases with increasing prescription depth for both seed types. Conclusions There exist ODD differences between 125I and 103Pd COMS plaques and the differences depend on DT, BD, plaque size, and prescription depth.
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Affiliation(s)
| | - Shih-Chi Lin
- Radiation Oncology, Norwalk Hospital, Norwalk, USA
| | - Yongbok Kim
- Radiation Oncology, Duke University, Durham, USA
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25
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Outpatient ocular brachytherapy: The USC Experience. Adv Radiat Oncol 2021; 6:100737. [PMID: 34307966 PMCID: PMC8283325 DOI: 10.1016/j.adro.2021.100737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/13/2021] [Accepted: 04/27/2021] [Indexed: 02/06/2023] Open
Abstract
Purpose Ocular brachytherapy is a standard-of-care surgical procedure for globe salvage in the treatment of uveal melanoma. The procedure involves the placement and subsequent removal of a radioactive plaque several days later. At many locations, patients are admitted on an inpatient basis until plaque removal due to radiation safety concerns. However, patients may be discharged to home after plaque insertion, and subsequently return to the medical facility for plaque removal. This study aimed to evaluate the safety and systematic financial benefit of the outpatient ocular brachytherapy program at "?>the University of Southern California (USC) Roski Eye Institute for 30 years. Methods and Materials A single-institution retrospective record review was performed on all 275 patients who underwent brachytherapy for ocular tumors between January 1, 1989 and December 31, 2019 to assess for occurrences of reportable radiation and/or patients safety events. The treatment protocols at our institution are described. Data on hospital-adjusted expenses per inpatient day from the American Hospital Association's 2018 Annual Survey were used as a proxy for costs to patients and the health care system to perform a cost–benefit analysis comparing outpatient versus inpatient brachytherapy. Results Of the 275 plaque procedures over a 30-year period that were reviewed, there were no internally or externally reportable patient or radiation safety events. There were no adverse events related to patient transportation to the hospital, the patient not returning for plaque removal, operative issues in removing the plaque on time due to cancelled or delayed cases, or loss of radioactive material. Additionally, our cost–benefit analysis estimates that outpatient brachytherapy reduced costs for USC’s patients in 2018 by an average of $24,722 per patient treated with ocular brachytherapy. Conclusions With appropriate measures, outpatient ocular brachytherapy allows patients to safely return home with the added benefit of decreased financial burden for both patients and the broader health care system.
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26
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Kaveckyte V, Carlsson Tedgren Å, Fernández-Varea JM. Impact of the I-value of diamond on the energy deposition in different beam qualities. Phys Med Biol 2021; 66. [PMID: 34014176 DOI: 10.1088/1361-6560/ac028f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 05/18/2021] [Indexed: 11/12/2022]
Abstract
Diamond detectors are increasingly employed in dosimetry. Their response has been investigated by means of Monte Carlo (MC) methods, but there is no consensus on what mass densityρ, mean excitation energyIand number of conduction electrons per atomnceto use in the simulations. The ambiguity occurs due to its seeming similarity with graphite (both are carbon allotropes). Except for the difference inρbetween crystalline graphite (2.265 g cm-3) and diamond (3.515 g cm-3), their dielectric properties are assumed to be identical. This is incorrect, and the two materials should be distinguished: (ρ= 2.265 g cm-3,I= 81.0 eV,nce= 1) for graphite and (ρ= 3.515 g cm-3,I= 88.5 eV,nce= 0) for diamond. Simulations done with the MC codepenelopeshow that the energy imparted in diamond decreases by up to 1% with respect to 'pseudo-diamond' (ρ= 3.515 g cm-3,I= 81.0 eV,nce= 0) depending on the beam quality and cavity thickness. The energy imparted changed the most in cavities that are small compared with the range of electrons. The difference in the density-effect term relative to graphite was the smallest for diamond owing to an interplay effect thatρ,Iandncehave on this term, in contrast to pseudo-diamond media when eitherρorIalone were adjusted. The study also presents a parameterized density-effect correction function for diamond that may be used by MC codes like EGSnrc. Theestarprogram assumes thatnce= 2 for all carbon-based materials, hence it delivers an erroneous density-effect correction term for graphite and diamond. Despite the small changes of the energy imparted in diamond simulated with two differentIvalues and expected close-to-negligible deviation from the published small-field output correction data, it is important to pay attention to material properties and model the medium faithfully.
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Affiliation(s)
- Vaiva Kaveckyte
- Department of Health, Medicine and Caring Sciences, Linköping University, SE-58185 Linköping, Sweden.,Department of Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, SE-17176 Stockholm, Sweden
| | - Åsa Carlsson Tedgren
- Department of Health, Medicine and Caring Sciences, Linköping University, SE-58185 Linköping, Sweden.,Department of Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, SE-17176 Stockholm, Sweden
| | - José M Fernández-Varea
- Facultat de Física (FQA and ICC), Universitat de Barcelona, Diagonal 645, E-08028 Barcelona, Catalonia, Spain
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27
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Dupere JM, Munro JJ, Medich DC. Shielded high dose rate ocular brachytherapy using Yb-169. Phys Med Biol 2021; 66. [PMID: 34010825 DOI: 10.1088/1361-6560/ac02d6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 05/19/2021] [Indexed: 11/12/2022]
Abstract
Purpose.We propose an approach for treating ocular melanoma using a new type of brachytherapy treatment device. This device couples Yb-169, a middle-energy high dose rate (HDR) brachytherapy source, with a gold shielded ring applicator to better conform radiation exposures to the tumor. In this study, we computationally test the dosimetric output of our proposed shielded ring applicator design using MCNP6 and validate it against an I-125 COMS plaque.Methods.The proposed Yb-169 ring applicator consists of an assembly of discrete sources delivered into an applicator with a conical collimated opening; this opening is tangent to the outside of the source tube. Using MCNP6, we simulated the dosimetric output of a ring of Yb-169 pellets placed within the collimator at various conical diameters and angles to demonstrate the dosimetric distribution for various prescription dose depths and target sizes using static intensity modulation.Results.Using various angles of collimation, the prescription dose was delivered to target apex depths of 3.5-8.0 mm into the eye covering target sizes ranging from 10 to 15 mm in diameter. This proposed device reduced the maximum absorbed dose to critical structures relative to I-125 by 5.2% to the posterior lens, 9.3% to the iris, 13.8% to the optic nerve, and 1.3% to the sclera.Conclusions.This proposed eye plaque design provides a more conformal dose distribution to the ocular tumor while minimizes dose to healthy ocular structures. In addition, the use of a middle-energy HDR brachytherapy source allows the use of a remote afterloader to expose the tumor after the plaque is sutured in place. This system is inherently safer and eliminates dose to the surgeon's hands.
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Affiliation(s)
- Justine M Dupere
- Worcester Polytechnic Institute, Worcester, MA 01609, United States of America
| | - John J Munro
- Montrose Technology Inc., North Andover, MA, 01845, United States of America
| | - David C Medich
- Worcester Polytechnic Institute, Worcester, MA 01609, United States of America
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Safigholi H, Parsons Z, Deering SG, Thomson RM. Update of the CLRP eye plaque brachytherapy database for photon-emitting sources. Med Phys 2021; 48:3373-3283. [PMID: 33735471 DOI: 10.1002/mp.14844] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 02/04/2021] [Accepted: 03/10/2021] [Indexed: 12/12/2022] Open
Abstract
PURPOSE To update and extend the Carleton Laboratory for Radiotherapy Physics (CLRP) Eye Plaque (EP) dosimetry database for low-energy photon-emitting brachytherapy sources using egs_brachy, an open-source EGSnrc application. The previous database, CLRP_EPv1, contained datasets for the Collaborative Ocular Melanoma Study (COMS) plaques (10-22 mm diameter) with 103 Pd or 125 I seeds (BrachyDose-computed, 2008). The new database, CLRP_EPv2, consists of newly calculated three-dimensional (3D) dose distributions for 17 plaques [eight COMS, five Eckert & Ziegler BEBIG, and four others representative of models used worldwide] for 103 Pd, 125 I, and 131 Cs seeds. ACQUISITION AND VALIDATION METHODS Plaque models are developed with egs_brachy, based on published/manufacturer dimensions and material data. The BEBIG plaques (modeled for the first time) are identical in dimensions to COMS plaques but differ in elemental composition and/or density. Previously benchmarked seed models are used. Eye plaques and seeds are simulated at the center of full-scatter water phantoms, scoring in (0.05 cm)3 voxels spanning the eye for scenarios: (a) "HOMO": simulated TG43 conditions; (b) "HETERO": eye plaques and seeds fully modeled; (c) "HETsi" (BEBIG only): one seed is active at a time with other seed geometries present but not emitting photons (inactive); summation over all i seeds in a plaque then yields "HETsum" (includes interseed effects). For validation, doses are compared to those from CLRP_EPv1 and published data. DATA FORMAT AND ACCESS Data are available at https://physics.carleton.ca/clrp/eye_plaque_v2, http://doi.org/10.22215/clrp/EPv2. The data consist of 3D dose distributions (text-based EGSnrc "3ddose" file format) and graphical presentations of the comparisons to previously published data. POTENTIAL APPLICATIONS The CLRP_EPv2 database provides accurate reference 3D dose distributions to advance ocular brachytherapy dose evaluations. The fully-benchmarked eye plaque models will be freely distributed with egs_brachy, supporting adoption of model-based dose evaluations as recommended by TG-129, TG-186, and TG-221.
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Affiliation(s)
- Habib Safigholi
- Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - Zack Parsons
- Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - Stephen G Deering
- Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - Rowan M Thomson
- Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa, ON, K1S 5B6, Canada
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Han G, Larocque M, Weis E, Menon G. Automatic optimization of treatment dosimetry to improve visual outcomes in episcleral plaque brachytherapy. Brachytherapy 2021; 20:433-445. [PMID: 33431339 DOI: 10.1016/j.brachy.2020.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/05/2020] [Accepted: 11/07/2020] [Indexed: 11/18/2022]
Abstract
PURPOSE The aim of this study was to develop an automated dose optimization algorithm, powered by simulated annealing, for inverse planning of ocular plaque brachytherapy treatments, to improve tumor coverage and critical structure sparing for reduced treatment-related morbidity. METHODS AND MATERIALS A simulated annealing based algorithm was built and evaluated by finding variable seed strengths that maximized dose uniformity across tumor base for model cases of various tumor heights and plaque sizes. This problem assessed its potential to find the minima in the energy function using differential loading. The algorithm was further developed to decrease doses to critical structures while maintaining desired tumor coverage. Doses to the optic disc and fovea were compared to those using uniform seed strengths for various model cases. Finally, 10 retrospective patient cases treated with uniform seed strengths were replanned with the developed algorithm to evaluate effectiveness for clinical application. RESULTS The developed algorithm achieved dose reductions of up to 37.3% and 39.6% to the optic disc and fovea, respectively, compared to those using uniform seed strengths, depending on the tumor and plaque size used for the model cases. Applying the algorithm to 10 clinical scenarios resulted in dose reductions of 14% to the optic disc and fovea relative to clinical treatments performed with uniform seed strengths. CONCLUSIONS The developed automatic dose optimization routine was able to achieve significant dose reductions to the critical structures relative to using uniformly loaded plaques both in the model and in the clinical cases.
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Affiliation(s)
- Gawon Han
- Division of Medical Physics, Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Matthew Larocque
- Division of Medical Physics, Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Ezekiel Weis
- Department of Ophthalmology, University of Alberta, Edmonton, Alberta, Canada; Department of Surgery, University of Calgary, Calgary, Alberta, Canada
| | - Geetha Menon
- Division of Medical Physics, Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Alberta, Canada.
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Itta F, Liuzzi R, Farella A, Porri G, Pacelli R, Conson M, Oliviero C, Buonanno F, Breve M, Cennamo G, Clemente S, Cella L. Personalized treatment planning in eye brachytherapy for ocular melanoma: Dosimetric analysis on ophthalmic structure at risk. Phys Med 2020; 76:285-293. [DOI: 10.1016/j.ejmp.2020.07.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/14/2020] [Accepted: 07/15/2020] [Indexed: 12/21/2022] Open
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Jiang P, Purtskhvanidze K, Kandzia G, Neumann D, Luetzen U, Siebert FA, Roider J, Dunst J. 106Ruthenium eye plaque brachytherapy in the management of medium sized uveal melanoma. Radiat Oncol 2020; 15:183. [PMID: 32727533 PMCID: PMC7392724 DOI: 10.1186/s13014-020-01621-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 07/15/2020] [Indexed: 12/29/2022] Open
Abstract
Background To evaluate 106Ruthenium Brachytherapy in management of medium sized uveal melanoma, with emphasis on 5-year outcome and toxicity. Methods From April 2007 to October 2015, 39 patients with medium sized uveal melanoma were treated with 106 Ru eye plaques brachytherapy. At the time of diagnosis, the mean tumor depth was 3.7 mm (±SD:1.6 mm). The mean dose at the tumor apex was 141.4 Gy (± SD: 12.1 Gy) and 557.7 Gy (± SD: 257.3 Gy) to the sclera. Results Mean follow-up was 69.5 months (± SD: 53.8 months). Thirty-four patients (87.1%) remained free of recurrence. Twenty-six patients (66.7%) demonstrated a complete tumor regression after a median period of 12 months (3–60 mon.). By the final examination, the visual acuity of 26 patients (66.7%) was better than 20/200, and 12 patients (30.7%) had a visual acuity better than 20/40. Retinopathy was detected in 11 patients (28.2%). After treatments only one patient (5.1%) had active vascular changes by the last examination. Moderate optic neuropathy was observed in 4 patients (10.3%). Cataract development was diagnosed in 21 patients (53.8%), and 16 patients (41%) had bilateral cataract development. Special emphasis was made on patients with larger tumors. Twelve out of the 39 patients had a tumor with a depth of 5 mm or more. There was no significant difference in local control or in side effects between both groups observed. Conclusions Our study proved 106Ru -brachytherapy to be an excellent treatment option with regard to tumor control and preservation of the visual acuity in well-selected patients. Our data suggested that this treatment is also suitable for tumors with a depth of more than 5 mm.
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Affiliation(s)
- Ping Jiang
- University Clinic for Medical Radiation Physics, Medical Campus Pius-Hospital, Carl von Ossietzky University, Georgstrasse 12, Oldenburg, Germany.
| | | | - Gerit Kandzia
- Department of Radiation Oncology, University Clinic Schleswig-Holstein, Campus Kiel, Germany
| | - Dirk Neumann
- Department of Radiation Oncology, University Clinic Schleswig-Holstein, Campus Kiel, Germany
| | - Ulf Luetzen
- Department of Nuclear Medicine, University Clinic Schleswig-Holstein, Campus Kiel, Germany
| | - Frank-André Siebert
- Department of Radiation Oncology, University Clinic Schleswig-Holstein, Campus Kiel, Germany
| | - Johann Roider
- Department of Ophthalmology, University Clinic Schleswig-Holstein, Campus Kiel, Germany
| | - Juergen Dunst
- University Clinic for Medical Radiation Physics, Medical Campus Pius-Hospital, Carl von Ossietzky University, Georgstrasse 12, Oldenburg, Germany.,Department of Radiation Oncology, University Clinic Schleswig-Holstein, Campus Kiel, Germany
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Lee YC, Lin SC, Kim Y. Optic disc dose reduction in ocular brachytherapy using 125 I notched COMS plaques: A simulation study based on current clinical practice. J Appl Clin Med Phys 2020; 21:57-70. [PMID: 32656945 PMCID: PMC7497926 DOI: 10.1002/acm2.12966] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 05/20/2020] [Accepted: 06/08/2020] [Indexed: 12/18/2022] Open
Abstract
PURPOSE Although notched Collaborative Ocular Melanoma Study (COMS) plaques have been widely used, optic disc dose reduction by notched COMS plaques has not been discussed in the literature. Therefore, this study investigated optic disc dose reduction in ocular brachytherapy using 125 I notched COMS plaques in comparison with optic disc dose for 125 I standard COMS plaques. METHODS For this simulation study, an in-house brachytherapy dose calculation program was developed using MATLAB software by incorporating the American Association of Physicists in Medicine Task Group-43 Update (AAPM TG-43U1) dosimetry formalism with a line source approximation in a homogeneous water medium and COMS seed coordinates in the AAPM TG 129. Using this program, optic disc doses for standard COMS plaques (from 12 to 22 mm in diameter in 2 mm increments) and notched COMS plaques with one seed removed (Case #1, from 12 to 22 mm) and with two seeds removed (Case #2, from 14 to 22 mm) were calculated as a function of tumor margin-to-optic disc distance (DT) for various tumor basal dimensions (BDs) for prescription depths from 1 to 10 mm in 1 mm intervals. A dose of 85 Gy for an irradiation time of 168 h was prescribed to each prescription depth. Then absolute and relative optic disc dose reduction by notched COMS plaques (Cases #1 and #2) was calculated for all prescription depths. RESULTS Optic disc dose reduction by notched COMS plaques (Cases #1 and #2) had five unique trends related to maximum optic disc dose reduction and corresponding optimal DT for each BD in each plaque. It increased with increasing prescription depth. CONCLUSIONS The results presented in this study would enable the clinician to choose an adequate plaque type among standard and notched 125 I COMS plaques and a prescription depth to minimize optic disc dose.
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Affiliation(s)
- Yongsook C Lee
- Department of Radiation Oncology, The University of Arizona, Tucson, AZ, USA
| | - Shih-Chi Lin
- Department of Radiation Oncology, The University of Arizona, Tucson, AZ, USA
| | - Yongbok Kim
- Department of Radiation Oncology, The University of Arizona, Tucson, AZ, USA
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