Impact of collimator leaf width and treatment technique on stereotactic radiosurgery and radiotherapy plans for intra- and extracranial lesions

Wu, Qiuwen; Wang, Zhiheng; Kirkpatrick, John P.; Chang, Zheng; Meyer, Jeffrey; Lü, Mei; Huntzinger, Calvin; Yin, Fang‐Fang

doi:10.1186/1748-717x-4-3

Cited by 70 publications

(72 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Appropriate devices for patient setup and immobilization.Appropriate devices for proper motion management.Computerized treatment verification system.Digital access to MRI and positron emission tomography (PET) image data.Capability to characterize and quantify internal anatomical changes with respiratory motion (for thoracic and abdominal SBRT services).Multimodality image fusion capability.Capability to calculate, display, and evaluate composite dose for patients who have received prior radiation therapy.Linac‐based treatment delivery system with appropriate mechanical accuracy, field‐aperture size, and resolution for small‐target conformality, and image‐guidance devices for target localization and verification including motion management technology relevant to the scope of SRS‐SBRT services to be offered 6, 7 …”

Section: Resourcesmentioning

confidence: 99%

See 1 more Smart Citation

AAPM‐RSS Medical Physics Practice Guideline 9.a. for SRS‐SBRT

Halvorsen

Cirino

Das

et al. 2017

J Applied Clin Med Phys

128

View full text Add to dashboard Cite

The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8,000 members and is the principal organization of medical physicists in the United States.The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States. Existing medical physics practice guidelines will be reviewed for revision or renewal, as appropriate, on their fifth anniversary or sooner.Each medical physics practice guideline represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guidelines and technical standards by those entities not providing these services is not authorized.The following terms are used in the AAPM practice guidelines: Must and Must Not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline.Should and Should Not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances. Approved by AAPM Professional Council 3‐31‐2017 and Executive Committee 4‐4‐2017.

show abstract

Section: Resourcesmentioning

confidence: 99%

“…Linac‐based treatment delivery system with appropriate mechanical accuracy, field‐aperture size, and resolution for small‐target conformality, and image‐guidance devices for target localization and verification including motion management technology relevant to the scope of SRS‐SBRT services to be offered 6, 7…”

Section: Resourcesmentioning

confidence: 99%

AAPM‐RSS Medical Physics Practice Guideline 9.a. for SRS‐SBRT

Halvorsen

Cirino

Das

et al. 2017

J Applied Clin Med Phys

128

View full text Add to dashboard Cite

show abstract

“…The advantage of the smaller leaf width has been studied by several groups [1][2][3][4][5][6][7][8][9][10][11], but with mixed results. Kubo et al [7] were the first to assess the conformity of threedimensional (3D) conformal plans using 1.7, 3 and 10 mm leaf width MLC systems.…”

mentioning

confidence: 99%

“…Burmeister et al [2], on the other hand, reported no apparent clinically significant difference between the 5 and 10 mm MLC systems on 3 patients treated with intensity-modulated radiotherapy except for very small target volumes or those with concavities that are small with respect to the MLC leaf width. More recently, Wu et al [11], in a preliminary evaluation of the dosimetric impact of a 2.5 mm MLC over the 5 mm MLC for various treatment techniques and for a subset of five brain tumour cases abutting the brainstem, showed that the 2.5 mm leaf width MLC in combination with the intensity-modulated radiotherapy technique can yield dosimetric benefits to the treatment of small lesions in cases involving complex target/organ-at-risk geometry. The current study was designed to provide a more comprehensive assessment of the performance of the 2.5 mm leaf MLC system over the 5 mm leaf system for target volumes characteristic of intracranial SRS, and assess if potential gains realised may be clinically meaningful.…”

mentioning

confidence: 99%

Impact of the high-definition multileaf collimator on linear accelerator-based intracranial stereotactic radiosurgery

Tanyi¹,

Kato²,

Chen³

et al. 2011

BJR

View full text Add to dashboard Cite

Objectives: The impact of two multileaf collimator (MLC) systems for linear accelerator-based intracranial stereotactic radiosurgery (SRS) was assessed. Methods: 68 lesions formed the basis of this study. 2.5 mm leaf width plans served as reference. Comparative plans, with identical planning parameters, were based on a 5 mm leaf width MLC system. Two collimation strategies, with collimation fixed at 0 u or 90 u and optimised per arc or beam, were also assessed. Dose computation was based on the pencil beam algorithm with allowance for tissue heterogeneity. Plan normalisation was such that 100% of the prescription dose covered 95% of the planning target volume. Plan evaluation was based on target coverage and normal tissue avoidance criteria. Results: The median conformity index difference between the MLC systems ranged between 0.8% and 14.2%; the 2.5 mm MLC exhibited better dose conformation. The median reduction of normal tissue exposed to >100%, >50% and >25% of the prescription dose ranged from 13.4% to 29.7%, favouring the 2.5 mm MLC system. Dose fall-off was steeper for the 2.5 mm MLC system with an overall median absolute difference ranging from 0.4 to 1.2 mm. The use of collimation optimisation resulted in a decrease in differences between the MLC systems. The results demonstrated the dosimetric merit of the 2.5 mm leaf width MLC system over the 5 mm leaf width system, albeit small, for the investigated range of intracranial SRS targets. Conclusion:The clinical significance of these results warrants further investigation to determine whether the observed dosimetric advantages translate into outcome improvements.

show abstract

“…They found a small dosimetric advantage of 2.5 mm leaf width MLC system over 5 mm MLC system in terms of dose conformation, normal tissue exposure, and a rapid dose falloff. Wu et al (20) evaluated 2.5 mm HDMLC versus 5 mm MMLC for three groups of tumor — spine, brain, and liver. They found that 2.5 mm finer leaf width in combination with IMRT could yield dosimetric benefits in radiosurgery and hypofractionated stereotactic radiotherapy (HSRT).…”

Section: Discussionmentioning

confidence: 99%

Is 5 mm MMLC suitable for VMAT‐based lung SBRT? A dosimetric comparison with 2.5 mm HDMLC using RTOG‐0813 treatment planning criteria for both conventional and high‐dose flattening filter‐free photon beams

Subramanian

Subramani

Swamy

et al. 2015

J Applied Clin Med Phys

View full text Add to dashboard Cite

The aim of this study is to assess the suitability of 5 mm millennium multileaf collimator (MMLC) for volumetric‐modulated arc therapy (VMAT)‐based lung stereotactic body radiotherapy (SBRT). Thirty lung SBRT patient treatment plans along with their planning target volumes (ranging from 2.01 cc to 150.11 cc) were transferred to an inhomogeneous lung phantom and retrospectively planned using VMAT technique, along with the high definition multileaf collimator (HDMLC) and MMLC systems. The plans were evaluated using Radiation Therapy Oncology Group (RTOG‐0813) treatment planning criteria for target coverage, normal tissue sparing, and treatment efficiency for both the MMLC and HDMLC systems using flat and flattening filter‐free (FFF) photon beams. Irrespective of the target volumes, both the MLC systems were able to satisfy the RTOG‐0813 treatment planning criteria without having any major deviation. Dose conformity was marginally better with HDMLC. The average conformity index (CI) value was found to be 1.069±0.034 and 1.075±0.0380 for HDMLC and MMLC plans, respectively. For the 6 MV FFF beams, the plan was slightly more conformal, with the average CI values of 1.063±0.029 and 1.073±0.033 for the HDMLC and MMLC plans, respectively. The high dose spillage was the maximum for 2 cc volume set (3% for HDMLC and 3.1% for MMLC). In the case of low dose spillage, both the MLCs were within the protocol of no deviation, except for the 2 cc volume set. The results from this study revealed that VMAT‐based lung SBRT using 5 mm MMLC satisfies the RTOG‐0813 treatment planning criteria for the studied target size and shapes.PACS numbers: 87.53.Ly, 87.53D, 87.56.jk

show abstract

Impact of collimator leaf width and treatment technique on stereotactic radiosurgery and radiotherapy plans for intra- and extracranial lesions

Cited by 70 publications

References 25 publications

AAPM‐RSS Medical Physics Practice Guideline 9.a. for SRS‐SBRT

AAPM‐RSS Medical Physics Practice Guideline 9.a. for SRS‐SBRT

Impact of the high-definition multileaf collimator on linear accelerator-based intracranial stereotactic radiosurgery

Is 5 mm MMLC suitable for VMAT‐based lung SBRT? A dosimetric comparison with 2.5 mm HDMLC using RTOG‐0813 treatment planning criteria for both conventional and high‐dose flattening filter‐free photon beams

Contact Info

Product

Resources

About