TY - JOUR
T1 - Image quality and stability of image-guided radiotherapy (IGRT) devices
T2 - A comparative study
AU - Stock, Markus
AU - Pasler, Marlies
AU - Birkfellner, Wolfgang
AU - Homolka, Peter
AU - Poetter, Richard
AU - Georg, Dietmar
PY - 2009/10
Y1 - 2009/10
N2 - INTRODUCTION: Our aim was to implement standards for quality assurance of IGRT devices used in our department and to compare their performances with that of a CT simulator.MATERIALS AND METHODS: We investigated image quality parameters for three devices over a period of 16months. A multislice CT was used as a benchmark and results related to noise, spatial resolution, low contrast visibility (LCV) and uniformity were compared with a cone beam CT (CBCT) at a linac and simulator.RESULTS: All devices performed well in terms of LCV and, in fact, exceeded vendor specifications. MTF was comparable between CT and linac CBCT. Integral nonuniformity was, on average, 0.002 for the CT and 0.006 for the linac CBCT. Uniformity, LCV and MTF varied depending on the protocols used for the linac CBCT. Contrast-to-noise ratio was an average of 51% higher for the CT than for the linac and simulator CBCT. No significant time trend was observed and tolerance limits were implemented.DISCUSSION: Reasonable differences in image quality between CT and CBCT were observed. Further research and development are necessary to increase image quality of commercially available CBCT devices in order for them to serve the needs for adaptive and/or online planning.
AB - INTRODUCTION: Our aim was to implement standards for quality assurance of IGRT devices used in our department and to compare their performances with that of a CT simulator.MATERIALS AND METHODS: We investigated image quality parameters for three devices over a period of 16months. A multislice CT was used as a benchmark and results related to noise, spatial resolution, low contrast visibility (LCV) and uniformity were compared with a cone beam CT (CBCT) at a linac and simulator.RESULTS: All devices performed well in terms of LCV and, in fact, exceeded vendor specifications. MTF was comparable between CT and linac CBCT. Integral nonuniformity was, on average, 0.002 for the CT and 0.006 for the linac CBCT. Uniformity, LCV and MTF varied depending on the protocols used for the linac CBCT. Contrast-to-noise ratio was an average of 51% higher for the CT than for the linac and simulator CBCT. No significant time trend was observed and tolerance limits were implemented.DISCUSSION: Reasonable differences in image quality between CT and CBCT were observed. Further research and development are necessary to increase image quality of commercially available CBCT devices in order for them to serve the needs for adaptive and/or online planning.
KW - Artifacts
KW - Computer Simulation
KW - Cone-Beam Computed Tomography/instrumentation
KW - Contrast Media
KW - Equipment Design
KW - Equipment Safety
KW - Humans
KW - Phantoms, Imaging
KW - Radiation Oncology/instrumentation
KW - Radiographic Image Interpretation, Computer-Assisted/instrumentation
KW - Radiography, Interventional
KW - Radiotherapy Planning, Computer-Assisted/instrumentation
KW - Radiotherapy, Computer-Assisted/instrumentation
KW - Radiotherapy, Conformal/instrumentation
KW - Tomography, X-Ray Computed/instrumentation
KW - Total Quality Management
UR - http://www.scopus.com/inward/record.url?scp=70349310249&partnerID=8YFLogxK
U2 - 10.1016/j.radonc.2009.07.012
DO - 10.1016/j.radonc.2009.07.012
M3 - Journal article
C2 - 19695725
SN - 0167-8140
VL - 93
SP - 1
EP - 7
JO - Radiotherapy and Oncology
JF - Radiotherapy and Oncology
IS - 1
ER -