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Puriparthi LV, Talluri AK, Akkineni NP, Bajwa HK, Tumu VR, Sresty NVNM, Alluri KR. Dosimetric Impact of Air Pockets in the Vaginal Cuff Brachytherapy Using Model-based Dose Calculation Algorithm. J Med Phys 2023; 48:373-377. [PMID: 38223798 PMCID: PMC10783181 DOI: 10.4103/jmp.jmp_88_23] [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] [Received: 07/05/2023] [Revised: 08/17/2023] [Accepted: 08/26/2023] [Indexed: 01/16/2024] Open
Abstract
Background Endometrial cancer is the most common disease of the female reproductive system. Vaginal cuff brachytherapy (VCB) has intrinsic advantages compared to external beam therapy when treated with radiation. A single-channel cylinder is a standard applicator in VCB. The present study aims to estimate a change in the dose to vaginal mucosa due to air pockets between the cylinder and vaginal mucosa by calculating with the Acuros BV algorithm and comparing it to the Task Group 43 (TG-43) algorithm. Materials and Methods Patients who presented with air packets were included retrospectively. For each patient, three plans were created: the first plan used TG-43, the second plan used dose recalculation with Acuros BV, and the third plan was generated by re-optimization by Acuros BV. On the same axial computed tomography image, the point doses at the cylinder's surface and the displaced mucosa were recorded and the ratios were then estimated. Results The average volume of air pockets was 0.08 cc (range of 0.01-0.3 cc), and 84% of air pockets displaced the vaginal mucosa by ≥0.2 cm. The average ratios of dose were 0.77 ± 0.09 (1 standard deviation [SD]) and 0.78 ± 0.09 (1 SD) for TG-43 and Acuros BV algorithms, respectively. Due to the air pocket, mucosa received a reduced dose by an average of 22.72% and an average of 23.29% for TG-43 and Acuros BV, respectively. The maximum displacement of mucosa and the ratio of doses were negatively correlated for both. In the Optimized Acuros BV plan, total dwell time increased by 1.8% but no considerable change in the dose ratios. Conclusion The calculated dose of mucous membrane forced out of the cylinder surface by air pockets by the Acuros BV algorithm was nonsignificantly different from TG-43. Therefore, even in the presence of air pockets, the TG-43 algorithm for calculating the VCB dose is appropriate.
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Affiliation(s)
- Lakshmi Venkataramana Puriparthi
- Department of Radiation Physics, Basavatarakam Indo American Cancer Hospital and Research Institute, Hyderabad, Telangana, India
| | - Anil Kumar Talluri
- Department of Radiation Physics, Basavatarakam Indo American Cancer Hospital and Research Institute, Hyderabad, Telangana, India
| | - Naga Prasanthi Akkineni
- Department of Radiation Oncology, Basavatarakam Indo American Cancer Hospital and Research Institute, Hyderabad, Telangana, India
| | - Harjot Kaur Bajwa
- Department of Radiation Oncology, American Oncology Institute, Hyderabad, Telangana, India
| | - Venkatappa Rao Tumu
- Department of Physics, National Institute of Technology, Warangal, Telangana, India
| | - N. V. N. Madhusudhana Sresty
- Department of Radiation Physics, Basavatarakam Indo American Cancer Hospital and Research Institute, Hyderabad, Telangana, India
| | - Krishnam Raju Alluri
- Department of Radiation Oncology, Basavatarakam Indo American Cancer Hospital and Research Institute, Hyderabad, Telangana, India
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Bi S, Chen Z, Sun X, Dai Z. Dosimetric comparison of AcurosBV with AAPM TG43 dose calculation formalism in cervical intraductal high‐dose‐rate brachytherapy using three different applicators. PRECISION RADIATION ONCOLOGY 2022. [DOI: 10.1002/pro6.1170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Su‐yan Bi
- National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Shenzhen China
| | - Zhi‐jian Chen
- National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Shenzhen China
| | - Xing‐ru Sun
- National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Shenzhen China
| | - Zhi‐tao Dai
- National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Shenzhen China
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Otal A, Celada F, Chimeno J, Vijande J, Pellejero S, Perez-Calatayud MJ, Villafranca E, Fuentemilla N, Blazquez F, Rodriguez S, Perez-Calatayud J. Review on Treatment Planning Systems for Cervix Brachytherapy (Interventional Radiotherapy): Some Desirable and Convenient Practical Aspects to Be Implemented from Radiation Oncologist and Medical Physics Perspectives. Cancers (Basel) 2022; 14:cancers14143467. [PMID: 35884528 PMCID: PMC9318845 DOI: 10.3390/cancers14143467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 07/10/2022] [Accepted: 07/14/2022] [Indexed: 11/16/2022] Open
Abstract
Intracavitary brachytherapy (BT, Interventional Radiotherapy, IRT), plays an essential role in the curative intent of locally advanced cervical cancer, for which the conventional approach involves external beam radiotherapy with concurrent chemotherapy followed by BT. This work aims to review the different methodologies used by commercially available treatment planning systems (TPSs) in exclusive magnetic resonance imaging-based (MRI) cervix BT with interstitial component treatments. Practical aspects and improvements to be implemented into the TPSs are discussed. This review is based on the clinical expertise of a group of radiation oncologists and medical physicists and on interactive demos provided by the software manufacturers. The TPS versions considered include all the new tools currently in development for future commercial releases. The specialists from the supplier companies were asked to propose solutions to some of the challenges often encountered in a clinical environment through a questionnaire. The results include not only such answers but also comments by the authors that, in their opinion, could help solve the challenges covered in these questions. This study summarizes the possibilities offered nowadays by commercial TPSs, highlighting the absence of some useful tools that would notably improve the planning of MR-based interstitial component cervix brachytherapy.
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Affiliation(s)
- Antonio Otal
- Medical Physics Department, Hospital Universitari Arnau de Vilanova, 25198 Lleida, 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), 46010 Valencia, Spain; (J.V.); (J.P.-C.)
- Correspondence: ; Tel.: +34-973248100
| | - Francisco Celada
- Radiotherapy Department, La Fe Hospital, 46026 Valencia, Spain; (F.C.); (M.-J.P.-C.)
| | - Jose Chimeno
- Medical Physics Department, Hospital San Juan, 03550 Alicante, Spain;
| | - Javier Vijande
- 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), 46010 Valencia, Spain; (J.V.); (J.P.-C.)
- Department of Atomic, Molecular and Nuclear Physics, University of Valencia, 46010 Valencia, Spain
- Instituto de Física Corpuscular, IFIC (UV-CSIC), 46010 Valencia, Spain
| | - Santiago Pellejero
- Radiation Oncology Department, Hospital Universitario de Navarra, 31008 Navarre, Spain; (S.P.); (E.V.); (N.F.)
| | | | - Elena Villafranca
- Radiation Oncology Department, Hospital Universitario de Navarra, 31008 Navarre, Spain; (S.P.); (E.V.); (N.F.)
| | - Naiara Fuentemilla
- Radiation Oncology Department, Hospital Universitario de Navarra, 31008 Navarre, Spain; (S.P.); (E.V.); (N.F.)
| | - Francisco Blazquez
- Radiotherapy Department, Hospital Clínica Benidorm, 03501 Alicante, Spain; (F.B.); (S.R.)
| | - Silvia Rodriguez
- Radiotherapy Department, Hospital Clínica Benidorm, 03501 Alicante, Spain; (F.B.); (S.R.)
| | - Jose Perez-Calatayud
- 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), 46010 Valencia, Spain; (J.V.); (J.P.-C.)
- Radiotherapy Department, La Fe Hospital, 46026 Valencia, Spain; (F.C.); (M.-J.P.-C.)
- Radiotherapy Department, Hospital Clínica Benidorm, 03501 Alicante, Spain; (F.B.); (S.R.)
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Yousif YAM, Osman AFI, Halato MA. A review of dosimetric impact of implementation of model-based dose calculation algorithms (MBDCAs) for HDR brachytherapy. Phys Eng Sci Med 2021; 44:871-886. [PMID: 34142317 DOI: 10.1007/s13246-021-01029-8] [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: 11/26/2020] [Accepted: 06/14/2021] [Indexed: 11/29/2022]
Abstract
To obtain dose distributions more physically representative to the patient anatomy in brachytherapy, calculation algorithms that can account for heterogeneity are required. The current standard AAPM Task Group No 43 (TG-43) dose calculation formalism has some clinically relevant dosimetric limitations. Lack of tissue heterogeneity and scattered dose corrections are the major weaknesses of the TG-43 formalism and could lead to systematic dose errors in target volumes and organs at risk. Over the last decade, model-based dose calculation algorithms (MBDCAs) have been clinically offered as complementary algorithms beyond the TG43 formalism for high dose rate (HDR) brachytherapy treatment planning. These algorithms provide enhanced dose calculation accuracy by using the information in the patient's computed tomography images, which allows modeling the patient's geometry, material compositions, and the treatment applicator. Several researchers have investigated the implementation of MBDCAs in HDR brachytherapy for dose optimization, but moving toward using them as primary algorithms for dose calculations is still lagging. Therefore, an overview of up-to-date research is needed to familiarize clinicians with the current status of the MBDCAs for different cancers in HDR brachytherapy. In this paper, we review the MBDCAs for HDR brachytherapy from a dosimetric perspective. Treatment sites covered include breast, gynecological, lung, head and neck, esophagus, liver, prostate, and skin cancers. Moreover, we discuss the current status of implementation of MBDCAs and the challenges.
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Affiliation(s)
- Yousif A M Yousif
- Department of Radiation Oncology, North West Cancer Centre-Tamworth Hospital, Tamworth, Australia.
| | - Alexander F I Osman
- Department of Medical Physics, Al-Neelain University, 11121, Khartoum, Sudan.
| | - Mohammed A Halato
- Department of Medical Physics, Al-Neelain University, 11121, Khartoum, Sudan
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Murphy L. The dosimetric effect of variations in source position on treatments using Leipzig-style brachytherapy skin applicators. Biomed Phys Eng Express 2020; 6:015031. [PMID: 33438619 DOI: 10.1088/2057-1976/ab6ecf] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Leipzig-style skin brachytherapy applicators are an excellent choice for the treatment of small surface lesions, since they can be used with a high dose rate source to produce a tightly constrained treatment field on the desired area of the skin. The dosimetry of these applicators is challenging to independently verify due to their small dimensions, complex energy spectrum and steep dose gradients. In particular the close proximity of the brachytherapy source to the treatment region is cause for concern, since small variations in the position of the radioactive source may significantly affect the resulting dose distribution. The aim of this work was to assess the dosimetry of these applicators using three independently techniques and use these results to examine the effect of variation in source position on the dose distribution. Simulation of different sized applicators in conjunction with a Gammamed + Ir192 source was performed using the EGSnrc Monte Carlo code. Dose distributions at the prescription depth and at the surface generated by Monte Carlo were compared to the outputs of a commercially available treatment planning system and measurements using radiochromic film. Source displacements of up to 0.5 mm in the vertical direction, 0.65 mm in the horizontal direction, and rotations of the source by up to 5° were all simulated. Changes in dose of over 6% at the prescription point and reductions in coverage at the 100% isodose level of several millimetres were observed even for small shifts of the source from its intended position. This work demonstrates that variation in the position of the radiation source is the dominant source of uncertainty in the use of these types of applicators. Centres wishing to perform treatments using these applicators are advised to take steps to control the uncertainty and ensure it remains at an acceptable level.
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Affiliation(s)
- Liam Murphy
- Department of Radiotherapy, NHS Grampian, Aberdeen, United Kingdom
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