TY - JOUR
T1 - A machine vision system with CCD cameras for patient positioning in radiotherapy
T2 - a preliminary report.
AU - Yoshitake, Tadamasa
AU - Nakamura, Katsumasa
AU - Shioyama, Yoshiyuki
AU - Sasaki, Tomonari
AU - Ohga, Saiji
AU - Yamaguchi, Toshihiro
AU - Toba, Takashi
AU - Anai, Shigeo
AU - Terashima, Hiromi
AU - Honda, Hiroshi
PY - 2005/12
Y1 - 2005/12
N2 - PURPOSE: To determine positioning accuracy of a machine vision system in radiotherapy. MATERIALS AND METHODS: The machine vision system was composed of 640 x 480 pixel CCD cameras and computerized control systems. For image acquisition, the phantom was set up for the reference position and a single CCD camera was positioned 1.5 m from the isocenter. The image data of the fiducial marker with 1.5 mm lead pellet on the lateral surface of the phantom was captured onto the CCD, and then the position of the marker was accurately calculated. The phantom was moved 0.25, 0.50, 0.75, 1.00, 2.00, and 3.00 mm from the reference position, using a micrometer head. The position of the fiducial marker was analyzed using a kilo-voltage fluoroscopic imaging system and a machine vision system. RESULTS: Using fluoroscopic images, the discrepancy between the actual movement of the phantom by micrometer heads and the measurement was found to be 0.12 +/- 0.05 mm (mean +/- standard deviation). In contrast, the detection of the movement by the machine vision system coincided with the discrepancy of 0.0067 +/- 0.0048 mm. CONCLUSION: This study suggests that the machine vision system can be used to measure small changes in patient position with a resolution of less than 0.1 mm.
AB - PURPOSE: To determine positioning accuracy of a machine vision system in radiotherapy. MATERIALS AND METHODS: The machine vision system was composed of 640 x 480 pixel CCD cameras and computerized control systems. For image acquisition, the phantom was set up for the reference position and a single CCD camera was positioned 1.5 m from the isocenter. The image data of the fiducial marker with 1.5 mm lead pellet on the lateral surface of the phantom was captured onto the CCD, and then the position of the marker was accurately calculated. The phantom was moved 0.25, 0.50, 0.75, 1.00, 2.00, and 3.00 mm from the reference position, using a micrometer head. The position of the fiducial marker was analyzed using a kilo-voltage fluoroscopic imaging system and a machine vision system. RESULTS: Using fluoroscopic images, the discrepancy between the actual movement of the phantom by micrometer heads and the measurement was found to be 0.12 +/- 0.05 mm (mean +/- standard deviation). In contrast, the detection of the movement by the machine vision system coincided with the discrepancy of 0.0067 +/- 0.0048 mm. CONCLUSION: This study suggests that the machine vision system can be used to measure small changes in patient position with a resolution of less than 0.1 mm.
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M3 - Article
C2 - 16562501
AN - SCOPUS:33744986269
VL - 96
SP - 399
EP - 405
JO - Fukuoka Acta Medica
JF - Fukuoka Acta Medica
SN - 0016-254X
IS - 12
ER -