Clinical commissioning and use of the Novalis Tx linear accelerator for SRS and SBRT

Jinkoo Kim, Ning Wen, Jian Yue Jin, Nicole Walls, Sangroh Kim, Haisen Li, Lei Ren, Yimei Huang, Anthony Doemer, Kathleen Faber, Tina Kunkel, Ahssan Balawi, Kimberly Garbarino, Kenneth Levin, Samir Patel, Munther Ajlouni, Brett Miller, Teamor Nurushev, Calvin Huntzinger, Raymond Schulz & 3 others Indrin J. Chetty, Benjamin Movsas, Samuel Ryu

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

The purpose of this study was to perform comprehensive measurements and testing of a Novalis Tx linear accelerator, and to develop technical guidelines for commissioning from the time of acceptance testing to the first clinical treatment. The Novalis Tx (NTX) linear accelerator is equipped with, among other features, a high-definition MLC (HD120 MLC) with 2.5 mm central leaves, a 6D robotic couch, an optical guidance positioning system, as well as X-ray-based image guidance tools to provide high accuracy radiation delivery for stereotactic radiosurgery and stereotactic body radiation therapy procedures. We have performed extensive tests for each of the components, and analyzed the clinical data collected in our clinic. We present technical guidelines in this report focusing on methods for: (1) efficient and accurate beam data collection for commissioning treatment planning systems, including small field output measurements conducted using a wide range of detectors; (2) commissioning tests for the HD120 MLC; (3) data collection for the baseline characteristics of the on-board imager (OBI) and ExacTrac X-ray (ETX) image guidance systems in conjunction with the 6D robotic couch; and (4) end-to-end testing of the entire clinical process. Established from our clinical experience thus far, recommendations are provided for accurate and efficient use of the OBI and ETX localization systems for intra- and extracranial treatment sites. Four results are presented. (1) Basic beam data measurements: Our measurements confirmed the necessity of using small detectors for small fields. Total scatter factors varied significantly (30% to approximately 62%) for small field measurements among detectors. Unshielded stereotactic field diode (SFD) overestimated dose by ~ 2% for large field sizes. Ion chambers with active diameters of 6 mm suffered from significant volume averaging. The sharpest profile penumbra was observed for the SFD because of its small active diameter (0.6 mm). (2) MLC commissioning: Winston Lutz test, light/radiation field congruence, and Picket Fence tests were performed and were within criteria established by the relevant task group reports. The measured mean MLC transmission and dynamic leaf gap of 6 MV SRS beam were 1.17% and 0.36 mm, respectively. (3) Baseline characteristics of OBI and ETX: The isocenter localization errors in the left/right, posterior/anterior, and superior/inferior directions were, respectively, -0.2 ± 0.2 mm, -0.8 ± 0.2 mm, and -0.8 ± 0.4 mm for ETX, and 0.5 ± 0.7 mm, 0.6 ± 0.5 mm, and 0.0 ± 0.5 mm for OBI cone-beam computed tomography. The registration angular discrepancy was 0.1 ± 0.2°, and the maximum robotic couch error was 0.2°. (4) End-to-end tests: The measured isocenter dose differences from the planned values were 0.8% and 0.4%, measured respectively by an ion chamber and film. The gamma pass rate, measured by EBT2 film, was 95% (3% DD and 1 mm DTA). Through a systematic series of quantitative commissioning experiments and end-to-end tests and our initial clinical experience, described in this report, we demonstrate that the NTX is a robust system, with the image guidance and MLC requirements to treat a wide variety of sites - in particular for highly accurate delivery of SRS and SBRT-based treatments.

Original languageEnglish (US)
Pages (from-to)124-151
Number of pages28
JournalJournal of Applied Clinical Medical Physics
Volume13
Issue number3
DOIs
StatePublished - May 10 2012

Fingerprint

Particle Accelerators
Linear accelerators
linear accelerators
Image sensors
X-Rays
Robotics
X rays
Ionization chambers
couches
Detectors
robotics
Diodes
Testing
Guidelines
Ions
Radiation
Fences
Cone-Beam Computed Tomography
Hepatocyte Growth Factor
ionization chambers

Keywords

  • Commissioning
  • Novalis tx
  • Stereotactic body radiation therapy
  • Stereotactic radiosurgery

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiation
  • Instrumentation

Cite this

Clinical commissioning and use of the Novalis Tx linear accelerator for SRS and SBRT. / Kim, Jinkoo; Wen, Ning; Jin, Jian Yue; Walls, Nicole; Kim, Sangroh; Li, Haisen; Ren, Lei; Huang, Yimei; Doemer, Anthony; Faber, Kathleen; Kunkel, Tina; Balawi, Ahssan; Garbarino, Kimberly; Levin, Kenneth; Patel, Samir; Ajlouni, Munther; Miller, Brett; Nurushev, Teamor; Huntzinger, Calvin; Schulz, Raymond; Chetty, Indrin J.; Movsas, Benjamin; Ryu, Samuel.

In: Journal of Applied Clinical Medical Physics, Vol. 13, No. 3, 10.05.2012, p. 124-151.

Research output: Contribution to journalArticle

Kim, J, Wen, N, Jin, JY, Walls, N, Kim, S, Li, H, Ren, L, Huang, Y, Doemer, A, Faber, K, Kunkel, T, Balawi, A, Garbarino, K, Levin, K, Patel, S, Ajlouni, M, Miller, B, Nurushev, T, Huntzinger, C, Schulz, R, Chetty, IJ, Movsas, B & Ryu, S 2012, 'Clinical commissioning and use of the Novalis Tx linear accelerator for SRS and SBRT', Journal of Applied Clinical Medical Physics, vol. 13, no. 3, pp. 124-151. https://doi.org/10.1120/jacmp.v13i3.3729
Kim, Jinkoo ; Wen, Ning ; Jin, Jian Yue ; Walls, Nicole ; Kim, Sangroh ; Li, Haisen ; Ren, Lei ; Huang, Yimei ; Doemer, Anthony ; Faber, Kathleen ; Kunkel, Tina ; Balawi, Ahssan ; Garbarino, Kimberly ; Levin, Kenneth ; Patel, Samir ; Ajlouni, Munther ; Miller, Brett ; Nurushev, Teamor ; Huntzinger, Calvin ; Schulz, Raymond ; Chetty, Indrin J. ; Movsas, Benjamin ; Ryu, Samuel. / Clinical commissioning and use of the Novalis Tx linear accelerator for SRS and SBRT. In: Journal of Applied Clinical Medical Physics. 2012 ; Vol. 13, No. 3. pp. 124-151.
@article{a128211b9e8141bd915559485bb81fde,
title = "Clinical commissioning and use of the Novalis Tx linear accelerator for SRS and SBRT",
abstract = "The purpose of this study was to perform comprehensive measurements and testing of a Novalis Tx linear accelerator, and to develop technical guidelines for commissioning from the time of acceptance testing to the first clinical treatment. The Novalis Tx (NTX) linear accelerator is equipped with, among other features, a high-definition MLC (HD120 MLC) with 2.5 mm central leaves, a 6D robotic couch, an optical guidance positioning system, as well as X-ray-based image guidance tools to provide high accuracy radiation delivery for stereotactic radiosurgery and stereotactic body radiation therapy procedures. We have performed extensive tests for each of the components, and analyzed the clinical data collected in our clinic. We present technical guidelines in this report focusing on methods for: (1) efficient and accurate beam data collection for commissioning treatment planning systems, including small field output measurements conducted using a wide range of detectors; (2) commissioning tests for the HD120 MLC; (3) data collection for the baseline characteristics of the on-board imager (OBI) and ExacTrac X-ray (ETX) image guidance systems in conjunction with the 6D robotic couch; and (4) end-to-end testing of the entire clinical process. Established from our clinical experience thus far, recommendations are provided for accurate and efficient use of the OBI and ETX localization systems for intra- and extracranial treatment sites. Four results are presented. (1) Basic beam data measurements: Our measurements confirmed the necessity of using small detectors for small fields. Total scatter factors varied significantly (30{\%} to approximately 62{\%}) for small field measurements among detectors. Unshielded stereotactic field diode (SFD) overestimated dose by ~ 2{\%} for large field sizes. Ion chambers with active diameters of 6 mm suffered from significant volume averaging. The sharpest profile penumbra was observed for the SFD because of its small active diameter (0.6 mm). (2) MLC commissioning: Winston Lutz test, light/radiation field congruence, and Picket Fence tests were performed and were within criteria established by the relevant task group reports. The measured mean MLC transmission and dynamic leaf gap of 6 MV SRS beam were 1.17{\%} and 0.36 mm, respectively. (3) Baseline characteristics of OBI and ETX: The isocenter localization errors in the left/right, posterior/anterior, and superior/inferior directions were, respectively, -0.2 ± 0.2 mm, -0.8 ± 0.2 mm, and -0.8 ± 0.4 mm for ETX, and 0.5 ± 0.7 mm, 0.6 ± 0.5 mm, and 0.0 ± 0.5 mm for OBI cone-beam computed tomography. The registration angular discrepancy was 0.1 ± 0.2°, and the maximum robotic couch error was 0.2°. (4) End-to-end tests: The measured isocenter dose differences from the planned values were 0.8{\%} and 0.4{\%}, measured respectively by an ion chamber and film. The gamma pass rate, measured by EBT2 film, was 95{\%} (3{\%} DD and 1 mm DTA). Through a systematic series of quantitative commissioning experiments and end-to-end tests and our initial clinical experience, described in this report, we demonstrate that the NTX is a robust system, with the image guidance and MLC requirements to treat a wide variety of sites - in particular for highly accurate delivery of SRS and SBRT-based treatments.",
keywords = "Commissioning, Novalis tx, Stereotactic body radiation therapy, Stereotactic radiosurgery",
author = "Jinkoo Kim and Ning Wen and Jin, {Jian Yue} and Nicole Walls and Sangroh Kim and Haisen Li and Lei Ren and Yimei Huang and Anthony Doemer and Kathleen Faber and Tina Kunkel and Ahssan Balawi and Kimberly Garbarino and Kenneth Levin and Samir Patel and Munther Ajlouni and Brett Miller and Teamor Nurushev and Calvin Huntzinger and Raymond Schulz and Chetty, {Indrin J.} and Benjamin Movsas and Samuel Ryu",
year = "2012",
month = "5",
day = "10",
doi = "10.1120/jacmp.v13i3.3729",
language = "English (US)",
volume = "13",
pages = "124--151",
journal = "Journal of applied clinical medical physics / American College of Medical Physics",
issn = "1526-9914",
publisher = "American Institute of Physics Publising LLC",
number = "3",

}

TY - JOUR

T1 - Clinical commissioning and use of the Novalis Tx linear accelerator for SRS and SBRT

AU - Kim, Jinkoo

AU - Wen, Ning

AU - Jin, Jian Yue

AU - Walls, Nicole

AU - Kim, Sangroh

AU - Li, Haisen

AU - Ren, Lei

AU - Huang, Yimei

AU - Doemer, Anthony

AU - Faber, Kathleen

AU - Kunkel, Tina

AU - Balawi, Ahssan

AU - Garbarino, Kimberly

AU - Levin, Kenneth

AU - Patel, Samir

AU - Ajlouni, Munther

AU - Miller, Brett

AU - Nurushev, Teamor

AU - Huntzinger, Calvin

AU - Schulz, Raymond

AU - Chetty, Indrin J.

AU - Movsas, Benjamin

AU - Ryu, Samuel

PY - 2012/5/10

Y1 - 2012/5/10

N2 - The purpose of this study was to perform comprehensive measurements and testing of a Novalis Tx linear accelerator, and to develop technical guidelines for commissioning from the time of acceptance testing to the first clinical treatment. The Novalis Tx (NTX) linear accelerator is equipped with, among other features, a high-definition MLC (HD120 MLC) with 2.5 mm central leaves, a 6D robotic couch, an optical guidance positioning system, as well as X-ray-based image guidance tools to provide high accuracy radiation delivery for stereotactic radiosurgery and stereotactic body radiation therapy procedures. We have performed extensive tests for each of the components, and analyzed the clinical data collected in our clinic. We present technical guidelines in this report focusing on methods for: (1) efficient and accurate beam data collection for commissioning treatment planning systems, including small field output measurements conducted using a wide range of detectors; (2) commissioning tests for the HD120 MLC; (3) data collection for the baseline characteristics of the on-board imager (OBI) and ExacTrac X-ray (ETX) image guidance systems in conjunction with the 6D robotic couch; and (4) end-to-end testing of the entire clinical process. Established from our clinical experience thus far, recommendations are provided for accurate and efficient use of the OBI and ETX localization systems for intra- and extracranial treatment sites. Four results are presented. (1) Basic beam data measurements: Our measurements confirmed the necessity of using small detectors for small fields. Total scatter factors varied significantly (30% to approximately 62%) for small field measurements among detectors. Unshielded stereotactic field diode (SFD) overestimated dose by ~ 2% for large field sizes. Ion chambers with active diameters of 6 mm suffered from significant volume averaging. The sharpest profile penumbra was observed for the SFD because of its small active diameter (0.6 mm). (2) MLC commissioning: Winston Lutz test, light/radiation field congruence, and Picket Fence tests were performed and were within criteria established by the relevant task group reports. The measured mean MLC transmission and dynamic leaf gap of 6 MV SRS beam were 1.17% and 0.36 mm, respectively. (3) Baseline characteristics of OBI and ETX: The isocenter localization errors in the left/right, posterior/anterior, and superior/inferior directions were, respectively, -0.2 ± 0.2 mm, -0.8 ± 0.2 mm, and -0.8 ± 0.4 mm for ETX, and 0.5 ± 0.7 mm, 0.6 ± 0.5 mm, and 0.0 ± 0.5 mm for OBI cone-beam computed tomography. The registration angular discrepancy was 0.1 ± 0.2°, and the maximum robotic couch error was 0.2°. (4) End-to-end tests: The measured isocenter dose differences from the planned values were 0.8% and 0.4%, measured respectively by an ion chamber and film. The gamma pass rate, measured by EBT2 film, was 95% (3% DD and 1 mm DTA). Through a systematic series of quantitative commissioning experiments and end-to-end tests and our initial clinical experience, described in this report, we demonstrate that the NTX is a robust system, with the image guidance and MLC requirements to treat a wide variety of sites - in particular for highly accurate delivery of SRS and SBRT-based treatments.

AB - The purpose of this study was to perform comprehensive measurements and testing of a Novalis Tx linear accelerator, and to develop technical guidelines for commissioning from the time of acceptance testing to the first clinical treatment. The Novalis Tx (NTX) linear accelerator is equipped with, among other features, a high-definition MLC (HD120 MLC) with 2.5 mm central leaves, a 6D robotic couch, an optical guidance positioning system, as well as X-ray-based image guidance tools to provide high accuracy radiation delivery for stereotactic radiosurgery and stereotactic body radiation therapy procedures. We have performed extensive tests for each of the components, and analyzed the clinical data collected in our clinic. We present technical guidelines in this report focusing on methods for: (1) efficient and accurate beam data collection for commissioning treatment planning systems, including small field output measurements conducted using a wide range of detectors; (2) commissioning tests for the HD120 MLC; (3) data collection for the baseline characteristics of the on-board imager (OBI) and ExacTrac X-ray (ETX) image guidance systems in conjunction with the 6D robotic couch; and (4) end-to-end testing of the entire clinical process. Established from our clinical experience thus far, recommendations are provided for accurate and efficient use of the OBI and ETX localization systems for intra- and extracranial treatment sites. Four results are presented. (1) Basic beam data measurements: Our measurements confirmed the necessity of using small detectors for small fields. Total scatter factors varied significantly (30% to approximately 62%) for small field measurements among detectors. Unshielded stereotactic field diode (SFD) overestimated dose by ~ 2% for large field sizes. Ion chambers with active diameters of 6 mm suffered from significant volume averaging. The sharpest profile penumbra was observed for the SFD because of its small active diameter (0.6 mm). (2) MLC commissioning: Winston Lutz test, light/radiation field congruence, and Picket Fence tests were performed and were within criteria established by the relevant task group reports. The measured mean MLC transmission and dynamic leaf gap of 6 MV SRS beam were 1.17% and 0.36 mm, respectively. (3) Baseline characteristics of OBI and ETX: The isocenter localization errors in the left/right, posterior/anterior, and superior/inferior directions were, respectively, -0.2 ± 0.2 mm, -0.8 ± 0.2 mm, and -0.8 ± 0.4 mm for ETX, and 0.5 ± 0.7 mm, 0.6 ± 0.5 mm, and 0.0 ± 0.5 mm for OBI cone-beam computed tomography. The registration angular discrepancy was 0.1 ± 0.2°, and the maximum robotic couch error was 0.2°. (4) End-to-end tests: The measured isocenter dose differences from the planned values were 0.8% and 0.4%, measured respectively by an ion chamber and film. The gamma pass rate, measured by EBT2 film, was 95% (3% DD and 1 mm DTA). Through a systematic series of quantitative commissioning experiments and end-to-end tests and our initial clinical experience, described in this report, we demonstrate that the NTX is a robust system, with the image guidance and MLC requirements to treat a wide variety of sites - in particular for highly accurate delivery of SRS and SBRT-based treatments.

KW - Commissioning

KW - Novalis tx

KW - Stereotactic body radiation therapy

KW - Stereotactic radiosurgery

UR - http://www.scopus.com/inward/record.url?scp=84866770010&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84866770010&partnerID=8YFLogxK

U2 - 10.1120/jacmp.v13i3.3729

DO - 10.1120/jacmp.v13i3.3729

M3 - Article

VL - 13

SP - 124

EP - 151

JO - Journal of applied clinical medical physics / American College of Medical Physics

JF - Journal of applied clinical medical physics / American College of Medical Physics

SN - 1526-9914

IS - 3

ER -