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Title: SU-F-T-556: A Potential Real Time AQA for Cyberknife Cones and MLC Based Treatments

Abstract

Purpose: To investigate the potential use of the Raven™ (LAP of America Laser Applications) for real time AQA of Cyberknife™ with InCise2 MLC (Accuray™ Medical). Methods: At setup, the Raven was rotated 45° on which an Accuray™ AQA cube was positioned. Three different AQA plans for fixed cone, InCise2MLC, and a modified MLC plan were delivered repeatedly ten times. The additional shapes in modified AQA plan enable additional reproducibility checks for all the MLC pairs. During the test, the cube was aligned by imbedded fiducials and irradiated. The two angled radiation beams aimed center tungsten ball of the cube and projected 45° to phosphor screen and registered by a CCD camera of the Raven device. The centricity of the metal ball in the irradiated field was then analyzed using Matlab codes. Results: For AP images, the average offsets of X, Y, and radial directions are 0.24 ± 0.04 mm, 0.25 ± 0.02 mm and 0.35 ±± 0.03 mm respectively for the cone; 0.34 ± 0.02 mm, 0.49 ± 0.04 mm and 0.60 ± 0.04 mm respectively for the MLC. For lateral images, they are 0.63 ± 0.05 mm, 0.11 ± 0.02 mm and 0.64 ± 0.04 mm respectively for themore » cone, 0.79 ± 0.08 mm, −0.23 ± 0.06 mm and 0.82 ± 0.09 mm respectively for the MLC. No inconsistent MLC shapes were found in the modified AQA group. Conclusion: The results are consistent with clinically acceptable values (≤1mm from baseline). The results suggest the potential of replacement of the standard AQA test with the novel real-time Raven device for Cyberknife daily QA. The modified MLC based AQA provides a more comprehensive MLC daily QA capability. Further improvements in its resolution and automatic analyzing capability are warranted.« less

Authors:
 [1]; ;  [2]; ;  [3];  [4]
  1. Boca Raton Regional Hospital, Boca Raton, FL (United States)
  2. Florida Atlantic University, Boca Raton, FL (United States)
  3. Lynn Cancer Institute, Boca Raton, FL (United States)
  4. Florida Atlantic University, Boca Raton, Florida (United States)
Publication Date:
OSTI Identifier:
22649131
Resource Type:
Journal Article
Resource Relation:
Journal Name: Medical Physics; Journal Volume: 43; Journal Issue: 6; Other Information: (c) 2016 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; 61 RADIATION PROTECTION AND DOSIMETRY; CHARGE-COUPLED DEVICES; CONES; POTENTIALS; RADIATION DOSES; RADIOTHERAPY

Citation Formats

Shang, C, Gibbard, G, Khanal, S, Cole, J, Schramm, A, and Leventouri, T. SU-F-T-556: A Potential Real Time AQA for Cyberknife Cones and MLC Based Treatments. United States: N. p., 2016. Web. doi:10.1118/1.4956741.
Shang, C, Gibbard, G, Khanal, S, Cole, J, Schramm, A, & Leventouri, T. SU-F-T-556: A Potential Real Time AQA for Cyberknife Cones and MLC Based Treatments. United States. doi:10.1118/1.4956741.
Shang, C, Gibbard, G, Khanal, S, Cole, J, Schramm, A, and Leventouri, T. 2016. "SU-F-T-556: A Potential Real Time AQA for Cyberknife Cones and MLC Based Treatments". United States. doi:10.1118/1.4956741.
@article{osti_22649131,
title = {SU-F-T-556: A Potential Real Time AQA for Cyberknife Cones and MLC Based Treatments},
author = {Shang, C and Gibbard, G and Khanal, S and Cole, J and Schramm, A and Leventouri, T},
abstractNote = {Purpose: To investigate the potential use of the Raven™ (LAP of America Laser Applications) for real time AQA of Cyberknife™ with InCise2 MLC (Accuray™ Medical). Methods: At setup, the Raven was rotated 45° on which an Accuray™ AQA cube was positioned. Three different AQA plans for fixed cone, InCise2MLC, and a modified MLC plan were delivered repeatedly ten times. The additional shapes in modified AQA plan enable additional reproducibility checks for all the MLC pairs. During the test, the cube was aligned by imbedded fiducials and irradiated. The two angled radiation beams aimed center tungsten ball of the cube and projected 45° to phosphor screen and registered by a CCD camera of the Raven device. The centricity of the metal ball in the irradiated field was then analyzed using Matlab codes. Results: For AP images, the average offsets of X, Y, and radial directions are 0.24 ± 0.04 mm, 0.25 ± 0.02 mm and 0.35 ±± 0.03 mm respectively for the cone; 0.34 ± 0.02 mm, 0.49 ± 0.04 mm and 0.60 ± 0.04 mm respectively for the MLC. For lateral images, they are 0.63 ± 0.05 mm, 0.11 ± 0.02 mm and 0.64 ± 0.04 mm respectively for the cone, 0.79 ± 0.08 mm, −0.23 ± 0.06 mm and 0.82 ± 0.09 mm respectively for the MLC. No inconsistent MLC shapes were found in the modified AQA group. Conclusion: The results are consistent with clinically acceptable values (≤1mm from baseline). The results suggest the potential of replacement of the standard AQA test with the novel real-time Raven device for Cyberknife daily QA. The modified MLC based AQA provides a more comprehensive MLC daily QA capability. Further improvements in its resolution and automatic analyzing capability are warranted.},
doi = {10.1118/1.4956741},
journal = {Medical Physics},
number = 6,
volume = 43,
place = {United States},
year = 2016,
month = 6
}
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