Intensity modulated radiotherapy treatment planning for dynamic multileaf collimator delivery: influence of different parameters on dose distributions

Samuelsson, Anna; Johansson, Karl-Axel

doi:10.1016/s0167-8140(02)00264-5

Cited by 20 publications

(3 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The weights (or "importance factors") are used by the planner to try to "steer" the optimization algorithm to more clinically desirable solutions (Webb, 2001), but this can be difficult since these weights are inherently imprecise and unintuitive (Bedford and Webb, 2003). The role of dose limits in IMRT optimization is also confusing, since it has been observed that in a penalty-based objective function, dose limits more stringent than are clinically necessary are frequently required to obtain convergence to an acceptable plan (see, e.g., (Samuelsson and Johansson, 2003, Spirou and Chui, 1998, Starkschall et al, 2001). …”

Section: Tunable Parameters In Imrt Objective Functionsmentioning

confidence: 99%

Reduced-order parameter optimization for simplifying prostate IMRT planning

Radke

Happersett

et al. 2007

Phys. Med. Biol.

View full text Add to dashboard Cite

Abstract.Intensity-modulated radiotherapy (IMRT) has become an effective tool for cancer treatment with radiation. However, even expert radiation planners still need to spend a substantial amount of time manually adjusting IMRT optimization parameters such as dose limits and costlet weights in order to obtain a clinically acceptable plan. In this paper, we describe two main advances that simplify the parameter adjustment process for five-field prostate IMRT planning. First, we report the results of a sensitivity analysis that quantifies the effect of each hand-tunable parameter of the IMRT cost function on each clinical objective and the overall quality of the resulting plan. Second, we show that a recursive random search over the 6 most sensitive parameters as an outer loop in IMRT planning can quickly and automatically determine parameters for the cost function that lead to a plan meeting the clinical requirements. Our experiments on a 10-patient dataset show that for 70% of the cases, we can automatically determine a plan in 10 minutes (on the average) that is either clinically acceptable or requires only minor adjustment by the planner. The outer loop optimization can be easily integrated into a traditional IMRT planning system.

show abstract

Section: Tunable Parameters In Imrt Objective Functionsmentioning

confidence: 99%

Reduced-order parameter optimization for simplifying prostate IMRT planning

Radke

Happersett

et al. 2007

Phys. Med. Biol.

View full text Add to dashboard Cite

show abstract

“…Intensity modulated radiotherapy (IMRT) is a sophisticated technique which requires specific quality control (QC) procedures. These procedures are related to all pieces of equipment or software components involved in the treatment chain, such as the treatment planning system (TPS) (Essers et al 2001, Samuelsson andJohansson 2003), the leaf motion calculator (LMC) or the multileaf collimator (MLC) (Chui et al 1996, Hamel 2000, Klein 1995, LoSasso et al 2001, Low 2001, Mubata et al 1997, Saw 2001. It is clear that the MLC characteristics and setting have a direct influence on the resulting dose distribution.…”

Section: Introductionmentioning

confidence: 99%

The sliding slit test for dynamic IMRT: a useful tool for adjustment of MLC related parameters

et al. 2005

View full text Add to dashboard Cite

For treatments with dynamic intensity modulated radiotherapy (IMRT), the adjustment of multileaf collimator (MLC) parameters affecting both the optimization algorithm and dose distributions is crucial. The main parameters characterizing the MLC are the transmission (T) and the dosimetric leaf separation (DLS). The aim of this study is twofold: a methodology based on the 'sliding slit' test is proposed to determine (T, DLS) combinations inducing the best conformity between calculations and measurements. Secondly, the effects of the MLC adjustment on measured dose and on optimization are presented for different configurations as the chair test and for the patient dosimetric quality control (DQC). Tests were performed with a Varian 23EX linac operated at 20 MV and equipped with a 120 leaf Millenium dynamic collimator. The treatment planning system was CadPlan/Helios (version 6.3.6). Results demonstrated that the sliding width (SW) strongly depends on the (T, DLS) combinations, and the measured dose is a linear function of the SW. Different (T, DLS) combinations induced a good agreement between calculations and measurements. The influence of the MLC calibration was found to be particularly important on the 'sliding slit' test (11.8% for a gap change of 0.8 mm) but not so much on the chair test and on the DQC. To detect small variations in leaf adjustment and to ensure consistency between calculation and actual dose delivered to patients, a daily check called IMRT MU check is proposed.

show abstract

“…Optimasi IMRT merupakan proses yang kompleks dan perlu dilakukan secara berulang untuk mencapai tujuan yang diinginkan. Hal ini membutuhkan pemilihan energi pancaran, jumlah segmen dan tingkat intensitas yang tepat (Pirzkall dkk., 2002) (Samuelsson & Johansson, 2003).…”

Section: Iunclassified

Perbandingan Dosimetri Perencanaan Radioterapi IMRT Menggunakan Fasilitas Beam Angle Optimization dan Teknik Manual Pada Kasus Kanker Nasofaring Stadium III

Syafna,

Adrial,

Diyona

2024

JFU

View full text Add to dashboard Cite

Telah dilakukan perbandingan dosimetri perencanaan Intensity Modulated Radiotherapy (IMRT) menggunakan fasilitas beam angle optimization (BAO) dan teknik manual pada kanker nasofaring (KNF) stadium III. Penelitian bertujuan untuk menganalisis nilai Conformity Index (CI), Homogeneity Index (HI), dan dosis Organ at Risk (OAR) pada kurva Dose Volume Histogram (DVH), serta jumlah Monitor Unit (MU). Terdapat empat variasi perencanaan yang diuji, yaitu IMRT 5 lapangan manual (M5), IMRT 5 lapangan otomatis (O5), IMRT 7 lapangan manual (M7), dan IMRT 7 lapangan otomatis (O7). Secara statistik hasil penelitian menunjukkan semua perencanaan pada Planning Target Volume 54 (PTV 54), PTV60, dan PTV70 hampir identik, namun perencanaan M5 lebih unggul karena memiliki nilai CI dan HI yang sesuai dengan International Commision on Radiation Units and Measurements (ICRU) Report 62, yaitu CI pada PTV54 (0,974±0,02), CI pada PTV60 (0,923±0,03), CI pada PTV70 (0,863±0,06), dan HI pada PTV54 (0,154±0,13), HI pada PTV60 (0,232±0,02), dan HI pada PTV70 (0,131±0,04). Selain itu, perencanaan M5 memenuhi ketetapan Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) untuk OAR. Jumlah MU yang lebih sedikit pada M5 dapat mengurangi komplikasi jangka panjang dan durasi penyinaran yang lebih singkat. Oleh karena itu, perencanaan M5 dianggap sebagai metode utama untuk kasus KNF stadium III.

show abstract

Intensity modulated radiotherapy treatment planning for dynamic multileaf collimator delivery: influence of different parameters on dose distributions

Cited by 20 publications

References 22 publications

Reduced-order parameter optimization for simplifying prostate IMRT planning

Reduced-order parameter optimization for simplifying prostate IMRT planning

The sliding slit test for dynamic IMRT: a useful tool for adjustment of MLC related parameters

Perbandingan Dosimetri Perencanaan Radioterapi IMRT Menggunakan Fasilitas Beam Angle Optimization dan Teknik Manual Pada Kasus Kanker Nasofaring Stadium III

Contact Info

Product

Resources

About