1
|
Bhushan M, Tripathi D, Yadav G, Kumar L, Chowdhary RL, Pahuja AK, Suresh T, Shukla SK, Mitra S. Feasibility of Monte-Carlo algorithm in comparison with collapse-cone dose calculation algorithm of a commercial treatment planning system in the presence of high-density metallic implant: a dosimetric study. J Egypt Natl Canc Inst 2021; 33:2. [PMID: 33415487 DOI: 10.1186/s43046-020-00057-x] [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: 07/09/2020] [Accepted: 12/20/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The number of people with implanted hip prosthesis has grown worldwide. For radiotherapy planning of patients with hip implants, few main challenges are encountered. The aim of the present study was to evaluate the feasibility of different planning algorithms in the presence of high-density metallic implant in the treatment of patients with carcinoma cervix. RESULTS It was found that D98% were 44.49 ± 0.11, 44.51 ± 0.13, 44.39 ± 0.22, and 44.45 ± 0.16 Gy for 4FMC6MV (4-field technique calculated with Monte-Carlo algorithm and 6 MV photon energy), 4FMC6MV_WP (4-field technique calculated with Monte-Carlo algorithm and 6 MV photon energy without prosthesis), 4FCC6MV (4-field technique calculated with collapse-cone-convolution algorithm and 6 MV photon energy), and 4FCC6MV_WP (4-field technique calculated with collapse-cone-convolution algorithm and 6 MV photon energy without prosthesis) respectively. Similarly, D2% were 49.40 ± 0.84, 49.05 ± 0.76, 48.97 ± 0.91, and 48.57 ± 0.85 Gray (Gy) for 4FMC6MV, 4FMC6MV_WP, 4FCC6MV, and 4FCC6MV_WP respectively. The present study has not suggested any major difference between the Monte-Carlo (MC) and collapse-cone-convolution (CCC) calculation algorithm in the presence of high-Z metallic implants. Volume of bowel receiving 15 Gy dose has shown a significant difference with prosthesis cases. This study investigates that hip prosthesis creates considerable changes in the treatment planning of cervical malignancies. CONCLUSION CCC algorithm is in good agreement with MC calculation algorithm in the presence of high-density metallic implants in terms of target coverage and avoidance organ sparing except few parameters.
Collapse
Affiliation(s)
- Manindra Bhushan
- Division of Medical Physics & Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Sector-5, Rohini, New Delhi, 110085, India. .,Amity School of Applied Sciences, Amity University (AUUP), Noida, India.
| | - Deepak Tripathi
- Amity School of Applied Sciences, Amity University (AUUP), Noida, India
| | - Girigesh Yadav
- Division of Medical Physics & Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Sector-5, Rohini, New Delhi, 110085, India
| | - Lalit Kumar
- Division of Medical Physics & Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Sector-5, Rohini, New Delhi, 110085, India.,Dr. APJ Abdul Kalam Technical University, Lucknow, UP, India
| | - Rahul Lal Chowdhary
- Division of Medical Physics & Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Sector-5, Rohini, New Delhi, 110085, India
| | - Anjali K Pahuja
- Division of Medical Physics & Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Sector-5, Rohini, New Delhi, 110085, India
| | - Tamilarasu Suresh
- Division of Medical Physics & Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Sector-5, Rohini, New Delhi, 110085, India
| | - Sushil Kumar Shukla
- Division of Medical Physics & Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Sector-5, Rohini, New Delhi, 110085, India
| | - Swarupa Mitra
- Division of Medical Physics & Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Sector-5, Rohini, New Delhi, 110085, India
| |
Collapse
|
2
|
Singh N, Painuly NK, Chaudhari LN, Chairmadurai A, Verma T, Shrotiya D, Bhatt CP. Evaluation of AAA and XVMC Algorithms for Dose Calculation in Lung Equivalent Heterogeneity in Photon Fields: A Comparison of Calculated Results with Measurements. J Biomed Phys Eng 2018; 8:223-230. [PMID: 30320026 PMCID: PMC6169117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 12/08/2015] [Indexed: 06/08/2023]
Abstract
AIMS The aims of the present work are (1) to evaluate dose calculation accuracy of two commonly used algorithms for 15 MV small photon fields in a medium encompassing heterogeneity and (2) to compare them with measured results obtained from gafchromic film EBT2. MATERIALS AND METHODS Authors employed kailwood (Pinus Wallichiana) to mimic lung. Briefly, seven Kailwood plates, each measuring 25x25 cm2 of varying thicknesses totaling 13 cm equivalent to the mean thickness of an adult human lung, were sandwiched between 5 cm tissue equivalent material from top and 10 cm below. Physical measurements were performed using Radiochromic film EBT2. The field sizes of 1x1, 2x2, 5x5 and 10x10 cm2 were selected at 100 cm SSD. Simulations were performed using EGSnrc/DOSRZnrc Monte Carlo code. The dose variation inside the inhomogeneity and near the interface was calculated using AAA & XVMC algorithm. RESULTS Preliminary results show that there is large variation of dose inside inhomogeneity. The maximum variation of dose inside the inhomogeneity for 1x1 cm2 was found 40% by AAA and 4.5% by XVMC compared to measured/simulated results. For the field size of 2x2 cm2, these figures were 27% by AAA & 3.5% by XVMC. For 5x5 cm2 field size, the variation is small which becomes insignificant for larger fields. CONCLUSION The results presented in this work indicate that for smaller fields, XVMC algorithm gives more realistic prediction, while there is the need for caution on using AAA algorithm for dose calculations involving small area irradiation encompassing heterogeneities and low-density media.
Collapse
Affiliation(s)
- N Singh
- Department of Radiotherapy, King George Medical University, Lucknow, India
| | - N K Painuly
- Department of Radiotherapy, King George Medical University, Lucknow, India
| | - L N Chaudhari
- M.S. Patel Cancer Center, Shree Krishna Hospital and Research Centre, Karamsad, Gujarat, India
| | - A Chairmadurai
- Department of Radiotherapy, Jaypee Hospital, Noida, Uttar Pradesh, India
| | - T Verma
- Department of Radiotherapy, King George Medical University, Lucknow, India
| | - D Shrotiya
- Department of Radiotherapy, J.K.Cancer Hospital, Kanpur, Uttar Pradesh, India
| | - C P Bhatt
- Department of Radiation Oncology, Batra Hospital, New Delhi, India
| |
Collapse
|
3
|
Impact of dose calculation algorithms on the dosimetric and radiobiological indices for lung stereotactic body radiotherapy (SBRT) plans calculated using LQ–L model. JOURNAL OF RADIOTHERAPY IN PRACTICE 2018. [DOI: 10.1017/s1460396917000735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractPurposeTo investigate discrepancies in dose calculation algorithms used for lung stereotactic body radiotherapy (SBRT) plans.Methods and materialsIn total, 30 patients lung SBRT treatment plans, initially generated using BrainLab Pencil Beam (BL_PB) algorithm for 10 Gy×5 Fractions to the planning target volume (PTV) were included in the study. These plans were recalculated using BrainLab Monte Carlo (BL_MC), Eclipse AAA (EC_AAA), Eclipse Acuros XB (EC_AXB) and ADAC Pinnacle CCC (AP_CCC) algorithms. Dose volume histograms of PTV were used to calculate dosimetric and radiobiological quality indices, and equivalent dose to 2 Gy per fraction using linear-quadratic-linear model. The BL_MC algorithm is considered gold standard tool to compare PTV parameters and quality indices to investigate dose calculation discrepancies of abovementioned plans.ResultsBL_PB overestimates doses that may be due to inability of the algorithm to properly account for electron scattering and transport in inhomogeneous medium. Compared with BL_MCNO plans, the EC_AAA and EC_AXB yield lower homogeneity indices and overestimate the dose in the penumbra region, whereas AP_CCC plans were comparable for small PTV (≈8 cc) and had significant difference for large PTV.ConclusionBL_PB algorithm overestimates PTV doses than BL_MC calculated doses. The EC_AAA, EC_AXB and AP_CCC algorithms calculate doses within acceptable limits of radiotherapy dose delivery recommendations.
Collapse
|
4
|
Arce P, Lagares JI. CPU time optimization and precise adjustment of the Geant4 physics parameters for a VARIAN 2100 C/D gamma radiotherapy linear accelerator simulation using GAMOS. Phys Med Biol 2018; 63:035007. [PMID: 29256451 DOI: 10.1088/1361-6560/aaa2b0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We have verified the GAMOS/Geant4 simulation model of a 6 MV VARIAN Clinac 2100 C/D linear accelerator by the procedure of adjusting the initial beam parameters to fit the percentage depth dose and cross-profile dose experimental data at different depths in a water phantom. Thanks to the use of a wide range of field sizes, from 2 × 2 cm2 to 40 × 40 cm2, a small phantom voxel size and high statistics, fine precision in the determination of the beam parameters has been achieved. This precision has allowed us to make a thorough study of the different physics models and parameters that Geant4 offers. The three Geant4 electromagnetic physics sets of models, i.e. Standard, Livermore and Penelope, have been compared to the experiment, testing the four different models of angular bremsstrahlung distributions as well as the three available multiple-scattering models, and optimizing the most relevant Geant4 electromagnetic physics parameters. Before the fitting, a comprehensive CPU time optimization has been done, using several of the Geant4 efficiency improvement techniques plus a few more developed in GAMOS.
Collapse
Affiliation(s)
- Pedro Arce
- Technology Department, Scientific Instrumentation Division, Medical Applications Unit, Centro de Investigaciones Energéticas, MedioAmbientales y Tecnológicas (CIEMAT), Madrid, Spain
| | | |
Collapse
|
5
|
Developing equations to predict surface dose and therapeutic interval in bolused electron fields: A Monte Carlo Study. Radiat Phys Chem Oxf Engl 1993 2017. [DOI: 10.1016/j.radphyschem.2017.02.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
6
|
Wi JM, Sung KH, Chi M. 'Orbital volume restoration rate after orbital fracture'; a CT-based orbital volume measurement for evaluation of orbital wall reconstructive effect. Eye (Lond) 2017; 31:713-719. [PMID: 28085134 DOI: 10.1038/eye.2016.311] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 11/27/2016] [Indexed: 11/09/2022] Open
Abstract
PurposeTo evaluate the effect of orbital reconstruction and factors related to the effect of orbital reconstruction by assessing of orbital volume using orbital computed tomography (CT) in cases of orbital wall fracture.MethodsIn this retrospective study, 68 patients with isolated blowout fractures were evaluated. The volumes of orbits and herniated orbital tissues were determined by CT scans using a three-dimensional reconstruction technique (the Eclipse Treatment Planning System). Orbital CT was performed preoperatively, immediately after surgery, and at final follow ups (minimum of 6 months). We evaluated the reconstructive effect of surgery making a new formula, 'orbital volume reconstruction rate' from orbital volume differences between fractured and contralateral orbits before surgery, immediately after surgery, and at final follow up.ResultsMean volume of fractured orbits before surgery was 23.01±2.60 cm3 and that of contralateral orbits was 21.31±2.50 cm3 (P=0.005). Mean volume of the fractured orbits immediately after surgery was 21.29±2.42 cm3, and that of the contralateral orbits was 21.33±2.52 cm3 (P=0.921). Mean volume of fractured orbits at final follow up was 21.50±2.44 cm3, and that of contralateral orbits was 21.32±2.50 cm3 (P=0.668). The mean orbital volume reconstruction rate was 100.47% immediately after surgery and 99.17% at final follow up. No significant difference in orbital volume reconstruction rate was observed with respect to fracture site or orbital implant type. Patients that underwent operation within 14 days of trauma had a better reconstruction rate at final follow up than patients who underwent operation over 14 days after trauma (P=0.039).ConclusionComputer-based measurements of orbital fracture volume can be used to evaluate the reconstructive effect of orbital implants and provide useful quantitative information. Significant reduction of orbital volume is observed immediately after orbital wall reconstruction surgery and the reconstruction effect is maintained for more than minimum 6 months. Patients that undergo surgery within 14 days of trauma has better reconstruction rates at final follow up, which supports the need for early surgery.
Collapse
Affiliation(s)
- J M Wi
- Department of Ophthalmology, Konyang University, Kim's Eye Hospital, Seoul, Korea
| | - K H Sung
- Department of Radiation Oncology, Gachon University Gil Medical Center, Incheon, Korea
| | - M Chi
- Department of Ophthalmology, Gachon University Gil Medical Center, Incheon, Korea
| |
Collapse
|
7
|
Wi JM, Kim YJ, Chi MJ. Orbital Wall Reconstruction with Osteoconductive Unsintered Hydroxyapatite/Poly L-Lactide. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2016. [DOI: 10.3341/jkos.2016.57.4.533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Jae Min Wi
- Department of Ophthalmology, Gachon University Gil Medical Center, Incheon, Korea
| | - Yu Jeong Kim
- Department of Ophthalmology, Gachon University Gil Medical Center, Incheon, Korea
| | - Mi Jung Chi
- Department of Ophthalmology, Gachon University Gil Medical Center, Incheon, Korea
| |
Collapse
|
8
|
Çatli S. High-density dental implants and radiotherapy planning: evaluation of effects on dose distribution using pencil beam convolution algorithm and Monte Carlo method. J Appl Clin Med Phys 2015; 16:46–52. [PMID: 26699323 PMCID: PMC5690165 DOI: 10.1120/jacmp.v16i5.5612] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2015] [Revised: 05/21/2015] [Accepted: 05/11/2015] [Indexed: 11/23/2022] Open
Abstract
High atomic number and density of dental implants leads to major problems at providing an accurate dose distribution in radiotherapy and contouring tumors and organs caused by the artifact in head and neck tumors. The limits and deficiencies of the algorithms using in the treatment planning systems can lead to large errors in dose calculation, and this may adversely affect the patient's treatment. In the present study, four commercial dental implants were used: pure titanium, titanium alloy (Ti-6Al-4V), amalgam, and crown. The effects of dental implants on dose distribution are determined with two methods: pencil beam convolution (PBC) algorithm and Monte Carlo code for 6 MV photon beam. The central axis depth doses were calculated on the phantom for a source-skin distance (SSD) of 100 cm and a 10 × 10 cm2 field using both of algorithms. The results of Monte Carlo method and Eclipse TPS were compared to each other and to those previously reported. In the present study, dose increases in tissue at a distance of 2 mm in front of the dental implants were seen due to the backscatter of electrons for dental implants at 6 MV using the Monte Carlo method. The Eclipse treatment planning system (TPS) couldn't precisely account for the backscatter radiation caused by the dental prostheses. TPS underestimated the back scatter dose and overestimated the dose after the dental implants. The large errors found for TPS in this study are due to the limits and deficiencies of the algorithms. The accuracy of the PBC algorithm of Eclipse TPS was evaluated in comparison to Monte Carlo calculations in consideration of the recommendations of the American Association of Physicists in Medicine Radiation Therapy Committee Task Group 65. From the comparisons of the TPS and Monte Carlo calculations, it is verified that the Monte Carlo simulation is a good approach to derive the dose distribution in heterogeneous media.
Collapse
|
9
|
Lu L. Dose calculation algorithms in external beam photon radiation therapy. INTERNATIONAL JOURNAL OF CANCER THERAPY AND ONCOLOGY 2013. [DOI: 10.14319/ijcto.0102.5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
|
10
|
Mesbahi A, Nejad FS. Monte Carlo study on the impact of spinal fixation rods on dose distribution in photon beams. Rep Pract Oncol Radiother 2007. [DOI: 10.1016/s1507-1367(10)60064-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
|