Wyniki wyszukiwania - Biblioteka Nauki

1

Entropy as a quality descriptor for the dose distribution - theory and practice for the patient target volume

100%

Moravek Z. , Bogner L.

Polish Journal of Medical Physics And Engineering

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2008

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tom 14

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nr 3

135-149

EN

The most common and established way to evaluate the quality of a radiotherapy plan is to use the dose-volume histogram (DVH). The evaluation of the DVH, however, is a subjective procedure. This may not be crucial as long as the two plans are significantly different. In the case of several plans obtained with different planning or optimisation strategies the differences are often subtle and therefore a more objective comparison method is desirable. A commonly used approach is based on evaluation of the conformity index, however we show how it can fail for plans of similar quality.Therefore we propose a new method based on the similarity of DVH to statistical distributions, which can be characterised uniquely by their entropy. The concept is defined separately for target volumes, where it is derived from the Fermi-like distribution, and for organs at risk, where the traditional approach is also considered in its derivation. The artificial illustratory and clinical examples show the properties of the entropy as the quality descriptor and compare it to the conformity index. The examples are focused to the patient target volumes, where the advantage of the concept is more evident.

2

Intensity modulated radiotherapy using Monte Carlo for routine postmastectomy radiotherapy

100%

Sayed Omer H. B. E.

Polish Journal of Medical Physics And Engineering

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2012

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tom 18

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nr 2

49-58

EN

Radiotherapy given after mastectomy (PMRT) will reduce the risk of local recurrence by about two-thirds. Clinical and dosimetric trials were carried out using various techniques to optimize the treatments by maximizing the dose to the tumour and minimizing it to the healthy tissues at proximity. Different conventional techniques which have been studied suffer from important dose inhomogeneities due to the complex anatomy of the chest, which reduces the benefits from such treatments. Moreover, due to the heterogeneity of breast cancer, the response to therapy and a systematic approach to treatment cannot be derived and treatment regimens must be determined on a patient-by-patient basis. This is only possible if accurate and fast treatment planning systems are available. Intensity Modulated Radiotherapy (IMRT) allows delivering higher doses to the target volume and limits the doses to the surrounding tissues. The objective of this study is to test the feasibility of applying a Monte Carlo-based treatment planning system, Hyperion accurately in routine Intensity Modulated Radiotherapy (IMRT) postmastectomy. In order to use a treatment planning system for routine work it should prove to provide optimized dose delivery in a suitable time. Treatment planning for IMRT application to PMRT was performed using Hyperion. Constraints were set to deliver the prescribed dose to the target and minimize the dose to the organs at risk. Dose Volume Histograms (DVH) were used to evaluate the set up plans. Time taken to optimize the plan was measured. The target coverage was within the accepted values. Approximately 90% of the breast and 80% of the PTV received 45 Gy or above. The volume of the lung that received 40Gy was less than 10% and the volume that received 20Gy (V20) was less than 25%. The volume of the heart receiving 30 Gy (V30) or above was negligible. This indicates low NTCP of these organs. The time taken for optimization, showed it possible to apply Monte Carlo-based treatment-planning systems for patient-to-patient PMRT.

3

Pułapki i nadzieje współczesnej radioterapii : spojrzenie klinicysty

89%

Topczewska-Bruns J. , Filipowski T.

Inżynier i Fizyk Medyczny

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2014

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tom Vol. 3, nr 5

247--250

PL

Radioterapia odgrywa ważną rolę w leczeniu nowotworów a nowoczesne technologie takie jak IMRT i VMAT są coraz bardziej dostępne w polskich Zakładach Radioterapii. Możliwości leczenia energią jonizującą gwałtownie wzrosły umożliwiając nowe sposoby leczenia pacjentów nawet z bardzo zaawansowanymi zmianami nowotworowymi. Rozwój inżynierii medycznej i technik komputerowych umożliwia dostarczenie bardzo konformalnego rozkładu dawki w obrębie obszarów tarczowych z jednoczesną ochroną zdrowych tkanek. Dzisiejsza radioterapia umożliwia leczenie pacjentów z dobra kontrolą miejscową, z niewielką ilością działań ubocznych a często w krótszym czasie niż to było przeszłości. Zaawansowane technologie wymagają ciągłego dokształcania wśród użytkowników aby zapewnić optymalne leczenie. W niniejszej pracy poglądowej przedstawiono kliniczne aspekty związane z zastosowaniem zaawansowanych technik radioterapii.

4

Web platform for research on IMRT algorithms

89%

Starzyński J. , Szmurło R. , Chaber B. , Krawczyk Z.

Przegląd Elektrotechniczny

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2016

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tom R. 92, nr 7

87--89

EN

The recent trends in software development force the transition from classical desktop-based programs into distributed systems offered over the Internet. The authors adapt this approach to the design of a collaborative radiotherapy planning system. The end users of the system are radiotherapy physiologists, medical staff, software developers and researchers developing new algorithms. A general concept and necessary components of such a system are presented.

PL

Aktualne trendy w rozwoju oprogramowania dyktują coraz powszechniejsze zastępowanie programów przeznaczonych do pracy na systemach stacjonarnych w systemy rozproszone dostępne za pośrednictwem sieci Internet. Autorzy niniejszego artykułu wykorzystują tę ideę do stworzenia systemu oprogramowania wspierającego współpracę fizyków radiologów, lekarzy, programistów oraz badaczy zajmujących się rozwojem algorytmów planowania radioterapii z modulowaną intensywnością dawki (IMRT). Artykuł przedstawia ogólna koncepcję takiego systemu oraz podstawowe komponenty z jakich powinien się składać.

5

Wyznaczanie jednorodnych dawek równoważnych dla pacjentów leczonych techniką Simultaneous Integrated Boost

89%

Araszkiewicz M. , Korgul A. , Kukołowicz P.

Inżynier i Fizyk Medyczny

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2020

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tom Vol. 9, nr 3

159--160

PL

Celem radioterapii jest dostarczenie zaplanowanej dawki promieniowania do targetu przy jednoczesnym zminimalizowaniu dawki deponowanej w narządach krytycznych. Istnieją przypadki, gdzie w planie leczenia jednego pacjenta uwzględniono kilka obszarów tarczowych (ang. Planning Target Volume – PTV). Jedną z możliwych technik napromieniania jest wtedy tzw. technika Simultaneous Integrated Boost (SIB). Polega ona na jednoczesnym napromienianiu różnymi dawkami więcej niż jednej objętości tarczowej. Ze względu na konieczność jednoczesnego podania dawek w kilku targetach otrzymują one dawkę różną od zleconej. W pracy, stosując koncepcję jednorodnej dawki równoważnej (ang. Equivalent Uniform Dose – EUD), oceniono wzajemny wpływ dawek deponowanych w poszczególnych targetach.

EN

Radiotherapy aims to deliver an appropriate dose of ionizing radiation to the target, minimizing the doses in critical organs. There are cases where several Planning Target Volume (PTV) are planned in the treatment plan for one patient that require different doses to be deposited. In such cases, one of the possible irradiation techniques is the so-called Simultaneous Integrated Boost (SIB) technique, in which all PTV are simultaneously irradiated with different doses. Due to the existing Beam Penumbra Effect, the application of a dose in one PTV affects the doses in the second PTV receiving a lower dose. In this paper, using the concept of the Equivalent Uniform Dose – EUD (EUD) the mutual influence of doses deposited in particular PTVs was assessed.

6

Dosimetric comparison of jaw tracking in intensity modulated and volumetric modulated arc radiotherapy for carcinoma of cervix

88%

Mani K. R. , Muneem M. A. , Sultana N. , Hossain T. , Basharat T. , Basu S. , Lingaiah R.

Polish Journal of Medical Physics and Engineering

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2019

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tom Vol. 25, Iss. 3

155--164

EN

Aim: To study the dosimetric advantages of the jaw tracking technique in intensity-modulated radiotherapy (IMRT) and volumetric modulated arc radiotherapy (VMAT) for carcinoma of cervix patients. Materials and Methods: We retrospectively selected ten previously treated cervix patients in this study. All the ten patients underwent CT simulation along with immobilization and positional devices. Targets and organ at risks (OARs) were delineated slice by slice for all the patients. All the patients were planned for IMRT and VMAT with intend to deliver 50 Gy in 25 fractions. All the plans were planned with 6 MV photon beam using millennium-120 multi leaf collimator (MLC) using the TrueBeam linear accelerator. IMRT and VMAT plans were performed with jaw tracking (JT) and with static jaw (SJ) techniques by keeping the same constraints and priorities for the target volumes and critical structures for a particular patient. For standardization, all the plans were normalized to the target mean of the planning target volume. All the plans were accepted with the criteria of bladder mean dose < 40 Gy and rectum mean dose < 40 Gy without compromising the target volumes. Target conformity, dose to the critical structures and low dose volumes were recorded and analyzed for IMRT and VMAT plans with and without jaw tracking for all the patients. Results: The conformity index average of all patients followed by standard deviation (̄x± σ̄x) for JT-IMRT, SJ-IMRT, JT-VMAT and SJ-VMAT were 1.176 ± 0.139, 1.175 ± 0.139, 1.193 ± 0.220 and 1.228 ± 0.192 and homogeneity index were 0.089 ± 0.022, 0.085 ± 0.024, 0.102 ± 0.016 and 0.101 ± 0.016. In low dose volume J,T-IMRT shows a 5.4% (p-value < 0.001) overall reduction in volume receiving at least 5 Gy (V5) compared to SJ-IMRT, whereas 1.2% reduction was observed in V5 volume in JT-VMAT compared to SJ-VMAT. JT-IMRT showed mean reduction in rectum and bladder of 1.34% (p-value < 0.001) and 1.46% (p-value < 0.001) compared to SJ-IMRT, while only 0.30% and 0.03% reduction were observed between JT-VMAT and SJ-VMAT. JT-IMRT plans also showed considerable dose reduction to inthe testine, right femoral head, left femoral head and cauda compared to the SJ-IMRT plans. Conclusion: Jaw tracking resulted in decreased dose to critical structures in IMRT and VMAT plans. But significant dose reductions were observed for critical structures in the JT-IMRT compared to SJ-IMRT technique. In JT-VMAT plans dose reduction to the critical structures were not significant compared to the JT-IMRT due to relatively lesser monitor units in the VMAT plans.

7

IMRT versus 3D-CRT for thyroid cancer

88%

Gizynska M. , Zawadzka A.

Polish Journal of Medical Physics And Engineering

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2008

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tom 14

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nr 3

151-162

EN

A 3D-CRT involving a 4-field (5-field, 6-field, etc.) technique (photon and electron beams) and an alternative IMRT 7-field technique with 6 MV photon fields for thyroid cancer were compared. The IMRT allows reduction in the dose to the spinal cord of about 12 Gy and permits better coverage of the target volume with smaller standard deviation (average 4.65% for 3D-CRT as compared with 1.81% for IMRT). The time needed to prepare therapy (TPS, dosimetry, preparing boluses and electron aperture) and the session time are about the same for both techniques.

8

Assesing multileaf collimator effect on the build-up region using Monte Carlo method

88%

Moreno M. , Teixeira N. , Jesus A. , Mora G.

Polish Journal of Medical Physics And Engineering

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2008

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tom 14

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nr 3

163-182

EN

Previous Monte Carlo studies have investigated the multileaf collimator (MLC) contribution to the build-up region for fields in which the MLC leaves were fully blocking the openings defined by the collimation jaws. In the present work, we investigate the same effect but for symmetric and asymmetric MLC defined field sizes (2×2, 4×4, 10×10 and 3×7 cm2). A Varian 2100C/D accelerator with 120-leaf MLC is accurately modeled for a 6MV photon beam using the BEAMnrc/EGSnrc code.Our results indicate that particles scattered from accelerator head and MLC are responsible for the increase of about 7% on the surface dose when comparing 2×2 and 10×10 cm2 fields. We found that the MLC contribution to the total build-up dose is about 2% for the 2×2 cm2 field and less than 1% for the largest fields.

9

Normal tissue objective (NTO) tool in Eclipse treatment planning system for dose distribution optimization

88%

Indrayani L. , Anam C. , Sutanto H. , Subroto R. , Dougherty G.

Polish Journal of Medical Physics and Engineering

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2022

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tom Vol. 28, Iss. 2

99--106

EN

Introduction: The purpose of this study was to determine the best normal tissue objective (NTO) values based on the dose distribution from brain tumor radiation therapy. Material and methods: The NTO is a constraint provided by Eclipse to limit the dose to normal tissues by steepening the dose gradient. The multitude of NTO setting combinations necessitates optimal NTO settings. The Eclipse supports manual and automatic NTOs. Fifteen patients were re-planned using NTO priorities of 1, 50, 100, 150, 200, and 500 in combination with dose fall-offs of 0.05, 0.1, 0.2, 0.3, 0.5, 1 and 5 mm-1. NTO distance to planning target volume (PTV), start dose, and end dose were 1 mm, 105%, and 60%, respectively, for all plans. In addition, planning without the NTO was arranged to find out its effect on planning. The prescription dose covered 95% of the PTV. Planning was evaluated using several indices: conformity index (CI), homogeneity index (HI), gradient index (GI), modified gradient index (mGI), comprehensive quality index (CQI), and monitor unit (MU). Differences among automatic NTO, manual NTO, and without NTO were evaluated using the Wilcoxon signed-rank test. Results: Comparisons obtained without and with manual NTO were: CI of 0.77 vs. 0.96 (p = 0.002), GI of 4.52 vs. 4.69 (p = 0.233), mGI of 4.93 vs. 3.95 (p = 0.001), HI of 1.10 vs. 1.10 (p = 0.330), and MU/cGy of 3.44 vs. 3.42 (p = 0.460). Planning without NTO produced a poor conformity index. Comparisons of automatic and manual NTOs were: CI of 0.92 vs. 0.96 (p = 0.035), GI of 5.25 vs. 4.69 (p = 0.253), mGI of 4.46 vs. 3.95 (p = 0.001), HI of 1.09 vs. 1.10 (p = 0.004), MU/cGy of 3.31 vs. 3.42 (p = 0.041). Conclusions: Based on these results, manual NTO with a priority of 100 and dose fall-off 0.5 mm-1 was optimal, as indicated by the high dose reduction in normal tissue.

10

Evaluation of the effect of random setup errors on dose delivery in Intensity Modulated Radiotherapy

88%

Bharati A. , Mandal S. R. , Srivastava A. K. , Rastogi M. , Khurana R. , Hadi R. , Sapru S. , Gandhi A. K. , Mishra S. P.

Polish Journal of Medical Physics and Engineering

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2020

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tom Vol. 26, Iss. 1

55--60

EN

Aim: To conduct a study on the effect of random setup errors inpatient for dose delivery in Intensity Modulated Radiotherapy plans using Octavius 4D phantom. Materials and methods: 11 patients with cancer of H&N were selected for this study. An IMRT plan was created for each patient. The IMRT quality assurance plans were transferred to Mosaiq workstation in a linear accelerator. These plans were delivered at the reference treatment position. Subsequently, the QA plans were delivered on the Octavius 4D phantom after introducing errors in various translational and rotational directions. The setup inaccuracies introduced varied from 1 mm to 5 mm along X, Y. These setup uncertainties were then introduced along X and Y direction simultaneously in equal measures. Similarly, IMRT plans were delivered also after introducing roll and yaw rotation of 1, 2 and 3 degrees in phantom. The deviation of gamma indices at all these positions was analyzed with respect to the reference setup position. Results: The percentage of points passing the gamma acceptance criterion decrease as we increase the setup error. The change is found to be very insignificant with setup error up to 2 mm along X, Y or XY direction. Similarly, the rotational error of up to 3 degrees is found to be acceptable. Conclusions: Small setup (< 2 mm) correction in patients may not adversely affect the dose delivery. But an error of similar magnitude in 2 directions simultaneously has a much greater impact on IMRT dose delivery.

11

Quality assurance and dosimetric analysis of intensity modulation radiotherapy using compensators for head and neck cancers

88%

Tyagi A. , Nangia S. , Chufal K. , Mishra M. , Ghosh D. , Supe S. , Singh M.

Polish Journal of Medical Physics And Engineering

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2009

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tom 15

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nr 4

193-208

EN

In this study we describe our experience in implementing compensator based intensity modulated radiotherapy (cIMRT) for head and neck cancer with regard to pre treatment quality assurance (QA), dosimetric parameters and other technical detail.This study represents the analysis of initial 48 patients who underwent cIMRT for head and neck cancers. All patients were treated with pre treatment QA in terms of point dose with ion chamber and spatial dose comparison with film dosimetry.In our study for all 48 patients, compensators revealed a deviation in central axis dose of 2% ± 1.8% in terms of cumulative calculated versus measured dose. Target coverage for high dose volume (70 Gy) was adequate in terms of volume receiving 93% and 95% of the prescription dose, which was 98.5% and 97.5% respectively. Parotid and other critical organs were spared adequately. Contralateral parotid (CLP) was spared. V30 Gy and V35 Gy was 55.9% and 36.8% for CLP and average dose was 31.7 Gy. Median variation in cumulative measured dose versus cumulative calculated dose was 1.8% (SD + 1.8) and mean variation was 2.5% (95%CI 1.5, 2.6). Range was 0 to 7%.cIMRT is practically feasible. Our QA tests revealed high degree of concordance between cumulative measured doses versus cumulative calculated doses. All dosimetric parameters were within acceptable limits. The manufacturing of compensator is cumbersome but it is a one time job followed by easy treatment delivery and simple QA procedure, high monitor unit (MU) efficiency and less treatment time. cIMRT is easy to implement and now can be applied to larger number of patients with different type of tumor.

12

Measurements of doses from photon beam irradiation and scattered neutrons in an anthropomorphic phantom model of prostate cancer: a comparison between 3DCRT, IMRT and tomotherapy

75%

Kowalik A. , Jackowiak W. , Malicki J. , Skórska M. , Adamczyk M. , Konstanty E. , Piotrowski T. , Polaczek-Grelik K.

Nukleonika

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2017

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tom Vol. 62, No. 1

29--35

EN

The rapid development of new radiotherapy technologies, such as intensity modulated radiotherapy (IMRT) or tomotherapy, has resulted in the capacity to deliver a more homogenous dose in the target. However, the higher doses associated with these techniques are a reason for concern because they may increase the dose outside the target. In the present study, we compared 3DCRT, IMRT and tomotherapy to assess the doses to organs at risk (OARs) resulting from photon beam irradiation and scattered neutrons. Material and methods. The doses to OARs outside the target were measured in an anthropomorphic Alderson phantom using thermoluminescence detectors (TLD 100) 6Li (7.5%) and 7Li (92.5%). The neutron fluence rate [cm–2·s–1] at chosen points inside the phantom was measured with gold foils (0.5 cm diameter, mean surface density of 0.108 g/cm3). Results. The doses [Gy] delivered to the OARs for 3DCRT, IMRT and tomotherapy respectively, were as follows: thyroid gland (0.62 ± 0.001 vs. 2.88 ± 0.004 vs. 0.58 ± 0.003); lung (0.99 ± 0.003 vs. 4.78 ± 0.006 vs. 0.67 ± 0.003); bladder (80.61 ± 0.054 vs. 53.75 ± 0.070 vs. 34.71 ± 0.059); and testes (4.38 ± 0.017 vs. 6.48 ± 0.013 vs. 4.39 ± 0.020). The neutron dose from 20 MV X-ray beam accounted for 0.5% of the therapeutic dose prescribed in the PTV. The further from the field edge the higher the contribution of this secondary radiation dose (from 8% to ~45%). Conclusion. For tomotherapy, all OARs outside the therapeutic field are well-spared. In contrast, IMRT achieved better sparing than 3DCRT only in the bladder. The photoneutron dose from the use of high-energy X-ray beam constituted a notable portion (0.5%) of the therapeutic dose prescribed to the PTV.

13

IMRT implementation and patient specific dose verification with film and ion chamber array detectors

75%

Saminathan S. , Manickam R. , Chandraraj V. , Supe S. , Keshava S.

Polish Journal of Medical Physics And Engineering

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2009

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tom 15

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nr 2

87-102

EN

Implementation of Intensity Modulation Radiotherapy (IMRT) and patient dose verification was carried out with film and I'mariXX using linear accelerator with 120-leaf Millennium dynamic multileaf collimator (dMLC). The basic mechanical and electrical commissioning and quality assurance tests of linear accelerator were carried out. The leaf position accuracy and leaf position repeatability checks were performed for static MLC positions. Picket fence test and garden fence test were performed to check the stability of the dMLC and the reproducibility of the gap between leaves. The radiation checks were performed to verify the position accuracy of MLCs in the collimator system. The dMLC dosimetric checks like output stability, average leaf transmission and dosimetric leaf separation were also investigated. The variation of output with gravitation at different gantry angles was found to be within 0.9%. The measured average leaf transmission for 6 MV was 1.6% and 1.8% for 18 MV beam. The dosimetric leaf separation was found to be 2.2 mm and 2.3 mm for 6 MV and 18 MV beams. In order to check the consistency of the stability and the precision of the dMLC, it is necessary to carryout regular weekly and monthly checks. The dynalog files analysis for Garden fence, leaf gap width and step wedge test patterns carried out weekly were in good agreement. Pretreatment verification was performed for 50 patients with ion chamber and I'matiXX device. The variations of calculated absolute dose for all treatment fields with the ion chamber measurement were within the acceptable criterion. Treatment Planning System (TPS) calculated dose distribution pattern was comparable with the I'matriXX measured dose distribution pattern. Out of 50 patients for which the comparison was made, 36 patients were agreed with the gamma pixel match of > 95% and 14 patients were with the gamma pixel match of 90-95% with the criteria of 3% delta dose (DD) and 3 mm distance-to-agreement (DTA). Commissioning and quality assurance of dMLC for IMRT application requires considerable time and effort. Many dosimetric characteristics need to be assessed carefully failing which the delivered dose will be significantly different from the planned dose. In addition to the issues discussed above we feel that individual MU check is necessary before the treatment is delivered.

14

Zastosowanie techniki VMAT z bramkowaniem oddechowym w radiochirurgii stereotaktycznej

71%

Ślosarek K. , Dolata Ł. , Kulik R. , Leszczyński W. , Osewski W.

Inżynier i Fizyk Medyczny

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2016

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tom Vol. 5, nr 4

191--197

PL

Radiochirurgia to sposób frakcjonowania dawki w radioterapii, polegający na podaniu kilku dużych dawek frakcyjnych w małej objętości. Jej realizację umożliwiają zaawansowane techniki dynamiczne. Jedną z nich jest technika, w której zastosowane są wiązki o zmiennym kształcie przy jednoczesnym obrocie głowicy akceleratora oraz zmiennej mocy dawki. Technikę tę określamy jako technikę obrotową z modulacją intensywności dawki VMAT (Volumetric Modulated Arc Therapy). Zmiany nowotworowe położone w strukturach anatomicznych zmieniających swoje położenie na skutek oddychania wymagają zastosowania techniki bramkowania oddechowego w celu zmniejszenia dawki w tkankach zdrowych otaczających guz nowotworowy. Bramkowanie oddechowe to technika, która polega na wyłączeniu ekspozycji promieniowania, kiedy guz nowotworowy znajduje się, wskutek oddychania pacjenta, poza wiązką promieniowania. Połączenie wyżej opisanych technik napromieniania z frakcjonowaniem radiochirurgicznym pozwala optymalnie wykorzystać oprogramowanie do obliczania rozkładu dawki, możliwości techniczne akceleratorów biomedycznych oraz radiobiologię w celu zwiększenia prawdopodobieństwa miejscowego wyleczenia. Jednak powiązanie technik napromieniania ze zmianą sposobu frakcjonowania dawki nie wystarczy, aby zastosować te metody w praktyce klinicznej. Czynnikiem niezbędnym jest obrazowe zweryfikowanie pozycji terapeutycznej pacjenta oraz dozymetryczne sprawdzenie poprawności obliczonego rozkładu dawki. Technika radiochirurgiczna z wykorzystaniem bramkowania oddechowego i VMAT omówiona zostanie na przykładzie pacjenta, który otrzymał dwa niezależne kursy radioterapii w odstępie ośmiu miesięcy. W celu zweryfikowania dawki całkowitej otrzymanej przez pacjenta zastosowano oprogramowanie do deformacji obrazu tomografii komputerowej, obrysów struktur oraz rozkładów dawki.

EN

Radiosurgery is the way of the dose fractionation were few high doses are delivered in small volume. It’s realization is possible due to dynamic techniques. One of such a technique is VMAT (Volumetric Modulated Arc Therapy) technique where the beams with variable shape are used together with accelerator gantry rotation and dose rate modulation. If cancerous lesions are located in anatomical structures, which one could change its position by patient breathing, then it is required to use respiratory gating system to reduce delivered dose to normal tissues surrounding the tumor. Respiratory gating system turns off the radiation when the tumor is outside the radiation beam due to patient breathing. The combination of respiratory gated VMAT technique with radiosurgery allows optimum use of the dose distribution calculating system, technical capabilities of biomedical accelerators and radiobiology in order to increase the probability of a local cure. However, the combination of irradiation techniques with the changes in the dose fractionation is not enough to apply these method in clinical practice. The image guided radiation therapy is the necessary factor to verify patient treatment position. Additionally dosimetry verification of the calculated dose distribution have to be done. The respiratory gated VMAT technique will be discussed on the example of a patient who received two independent radiotherapy courses (with eight months break between). To verify the total dose, received by the patient, the dedicated software was used to perform deformation of the computed tomography volume, structures outlines and dose distributions.