Quality assurance device for four-dimensional IMRT or SBRT and respiratory gating using patient-specific intrafraction motion kernels

Benjamin E. Nelms, Eric Ehler, Henry Bragg, Wolfgang A. Tome

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

Emerging technologies such as four-dimensional computed tomography (4D CT) and implanted beacons are expected to allow clinicians to accurately model intrafraction motion and to quantitatively estimate internal target volumes (ITVs) for radiation therapy involving moving targets. In the case of intensity-modulated (IMRT) and stereotactic body radiation therapy (SBRT) delivery, clinicians must consider the interplay between the temporal nature of the modulation and the target motion within the ITV. A need exists for a 4D IMRT/SBRT quality assurance (QA) device that can incorporate and analyze customized intrafraction motion as it relates to dose delivery and respiratory gating. We built a 4D IMRT/SBRT prototype device and entered (X, Y, Z)(T) coordinates representing a motion kernel into a software application that. 1. transformed the kernel into beam-specific two-dimensional (2D) motion 2:projections," 2. previewed the motion in real time, and 3. drove a precision X-Y motorized device that had, atop it, a mounted planar IMRT QA measurement device. The detectors that intersected the target in the beam's-eye-view of any single phase of the breathing cycle (a small subset of all the detectors) were defined as "target detectors" to be analyzed for dose uniformity between multiple fractions. Data regarding the use of this device to quantify dose variation fraction-to -fraction resulting from target motion (for several delivery modalities and with and without gating) have been recently published. A combined software and hardware solution for patient-customized 4D IMRT/SBRT QA is an effective tool for assessing IMRT delivery under conditions of intrafraction motion. The 4D IMRT QA device accurately reproduced the projected motion kernels for all beam's-eye-view motion kernels. This device has been proved to • effectively quantify the degradation in dose uniformity resulting from a moving target within a static planning target volume, and • integrate with a commercial respiratory gating system to ensure that the system is working effectively. Such a device is discussed as a potential tool to optimize the gating duty cycle to maximize delivery efficiency while minimizing dose variability.

Original languageEnglish (US)
Pages (from-to)152-168
Number of pages17
JournalJournal of Applied Clinical Medical Physics
Volume8
Issue number4
StatePublished - Sep 2007
Externally publishedYes

Fingerprint

Radiotherapy
assurance
Quality assurance
radiation therapy
Equipment and Supplies
delivery
Detectors
dosage
Four-Dimensional Computed Tomography
Application programs
Tomography
detectors
Software
respiratory system
Modulation
computer programs
Hardware
Planning
Degradation
beacons

Keywords

  • 4D
  • IMRT
  • IMRT QA
  • Intrafraction motion
  • ITV
  • Quality assurance
  • SBRT

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiation
  • Instrumentation

Cite this

Quality assurance device for four-dimensional IMRT or SBRT and respiratory gating using patient-specific intrafraction motion kernels. / Nelms, Benjamin E.; Ehler, Eric; Bragg, Henry; Tome, Wolfgang A.

In: Journal of Applied Clinical Medical Physics, Vol. 8, No. 4, 09.2007, p. 152-168.

Research output: Contribution to journalArticle

@article{e4aeee4176c14d098da9fede226b511c,
title = "Quality assurance device for four-dimensional IMRT or SBRT and respiratory gating using patient-specific intrafraction motion kernels",
abstract = "Emerging technologies such as four-dimensional computed tomography (4D CT) and implanted beacons are expected to allow clinicians to accurately model intrafraction motion and to quantitatively estimate internal target volumes (ITVs) for radiation therapy involving moving targets. In the case of intensity-modulated (IMRT) and stereotactic body radiation therapy (SBRT) delivery, clinicians must consider the interplay between the temporal nature of the modulation and the target motion within the ITV. A need exists for a 4D IMRT/SBRT quality assurance (QA) device that can incorporate and analyze customized intrafraction motion as it relates to dose delivery and respiratory gating. We built a 4D IMRT/SBRT prototype device and entered (X, Y, Z)(T) coordinates representing a motion kernel into a software application that. 1. transformed the kernel into beam-specific two-dimensional (2D) motion 2:projections,{"} 2. previewed the motion in real time, and 3. drove a precision X-Y motorized device that had, atop it, a mounted planar IMRT QA measurement device. The detectors that intersected the target in the beam's-eye-view of any single phase of the breathing cycle (a small subset of all the detectors) were defined as {"}target detectors{"} to be analyzed for dose uniformity between multiple fractions. Data regarding the use of this device to quantify dose variation fraction-to -fraction resulting from target motion (for several delivery modalities and with and without gating) have been recently published. A combined software and hardware solution for patient-customized 4D IMRT/SBRT QA is an effective tool for assessing IMRT delivery under conditions of intrafraction motion. The 4D IMRT QA device accurately reproduced the projected motion kernels for all beam's-eye-view motion kernels. This device has been proved to • effectively quantify the degradation in dose uniformity resulting from a moving target within a static planning target volume, and • integrate with a commercial respiratory gating system to ensure that the system is working effectively. Such a device is discussed as a potential tool to optimize the gating duty cycle to maximize delivery efficiency while minimizing dose variability.",
keywords = "4D, IMRT, IMRT QA, Intrafraction motion, ITV, Quality assurance, SBRT",
author = "Nelms, {Benjamin E.} and Eric Ehler and Henry Bragg and Tome, {Wolfgang A.}",
year = "2007",
month = "9",
language = "English (US)",
volume = "8",
pages = "152--168",
journal = "Journal of Applied Clinical Medical Physics",
issn = "1526-9914",
publisher = "American Institute of Physics Publising LLC",
number = "4",

}

TY - JOUR

T1 - Quality assurance device for four-dimensional IMRT or SBRT and respiratory gating using patient-specific intrafraction motion kernels

AU - Nelms, Benjamin E.

AU - Ehler, Eric

AU - Bragg, Henry

AU - Tome, Wolfgang A.

PY - 2007/9

Y1 - 2007/9

N2 - Emerging technologies such as four-dimensional computed tomography (4D CT) and implanted beacons are expected to allow clinicians to accurately model intrafraction motion and to quantitatively estimate internal target volumes (ITVs) for radiation therapy involving moving targets. In the case of intensity-modulated (IMRT) and stereotactic body radiation therapy (SBRT) delivery, clinicians must consider the interplay between the temporal nature of the modulation and the target motion within the ITV. A need exists for a 4D IMRT/SBRT quality assurance (QA) device that can incorporate and analyze customized intrafraction motion as it relates to dose delivery and respiratory gating. We built a 4D IMRT/SBRT prototype device and entered (X, Y, Z)(T) coordinates representing a motion kernel into a software application that. 1. transformed the kernel into beam-specific two-dimensional (2D) motion 2:projections," 2. previewed the motion in real time, and 3. drove a precision X-Y motorized device that had, atop it, a mounted planar IMRT QA measurement device. The detectors that intersected the target in the beam's-eye-view of any single phase of the breathing cycle (a small subset of all the detectors) were defined as "target detectors" to be analyzed for dose uniformity between multiple fractions. Data regarding the use of this device to quantify dose variation fraction-to -fraction resulting from target motion (for several delivery modalities and with and without gating) have been recently published. A combined software and hardware solution for patient-customized 4D IMRT/SBRT QA is an effective tool for assessing IMRT delivery under conditions of intrafraction motion. The 4D IMRT QA device accurately reproduced the projected motion kernels for all beam's-eye-view motion kernels. This device has been proved to • effectively quantify the degradation in dose uniformity resulting from a moving target within a static planning target volume, and • integrate with a commercial respiratory gating system to ensure that the system is working effectively. Such a device is discussed as a potential tool to optimize the gating duty cycle to maximize delivery efficiency while minimizing dose variability.

AB - Emerging technologies such as four-dimensional computed tomography (4D CT) and implanted beacons are expected to allow clinicians to accurately model intrafraction motion and to quantitatively estimate internal target volumes (ITVs) for radiation therapy involving moving targets. In the case of intensity-modulated (IMRT) and stereotactic body radiation therapy (SBRT) delivery, clinicians must consider the interplay between the temporal nature of the modulation and the target motion within the ITV. A need exists for a 4D IMRT/SBRT quality assurance (QA) device that can incorporate and analyze customized intrafraction motion as it relates to dose delivery and respiratory gating. We built a 4D IMRT/SBRT prototype device and entered (X, Y, Z)(T) coordinates representing a motion kernel into a software application that. 1. transformed the kernel into beam-specific two-dimensional (2D) motion 2:projections," 2. previewed the motion in real time, and 3. drove a precision X-Y motorized device that had, atop it, a mounted planar IMRT QA measurement device. The detectors that intersected the target in the beam's-eye-view of any single phase of the breathing cycle (a small subset of all the detectors) were defined as "target detectors" to be analyzed for dose uniformity between multiple fractions. Data regarding the use of this device to quantify dose variation fraction-to -fraction resulting from target motion (for several delivery modalities and with and without gating) have been recently published. A combined software and hardware solution for patient-customized 4D IMRT/SBRT QA is an effective tool for assessing IMRT delivery under conditions of intrafraction motion. The 4D IMRT QA device accurately reproduced the projected motion kernels for all beam's-eye-view motion kernels. This device has been proved to • effectively quantify the degradation in dose uniformity resulting from a moving target within a static planning target volume, and • integrate with a commercial respiratory gating system to ensure that the system is working effectively. Such a device is discussed as a potential tool to optimize the gating duty cycle to maximize delivery efficiency while minimizing dose variability.

KW - 4D

KW - IMRT

KW - IMRT QA

KW - Intrafraction motion

KW - ITV

KW - Quality assurance

KW - SBRT

UR - http://www.scopus.com/inward/record.url?scp=38049144728&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=38049144728&partnerID=8YFLogxK

M3 - Article

C2 - 18449156

AN - SCOPUS:38049144728

VL - 8

SP - 152

EP - 168

JO - Journal of Applied Clinical Medical Physics

JF - Journal of Applied Clinical Medical Physics

SN - 1526-9914

IS - 4

ER -