Quality assurance of a gimbaled head swing verification using feature point tracking.
To perform dynamic tumor tracking (DTT) for clinical applications safely and accurately, gimbaled head swing verification is important. We propose a quantitative gimbaled head swing verification method for daily quality assurance (QA), which uses feature point tracking and a web camera. The web camera was placed on a couch at the same position for every gimbaled head swing verification, and could move based on a determined input function (sinusoidal patterns; amplitude: ± 20 mm; cycle: 3 s) in the pan and tilt directions at isocenter plane. Two continuous images were then analyzed for each feature point using the pyramidal Lucas-Kanade (LK) method, which is an optical flow estimation algorithm. We used a tapped hole as a feature point of the gimbaled head. The period and amplitude were analyzed to acquire a quantitative gimbaled head swing value for daily QA. The mean ± SD of the period were 3.00 ± 0.03 (range: 3.00-3.07) s and 3.00 ± 0.02 (range: 3.00-3.07) s in the pan and tilt directions, respectively. The mean ± SD of the relative displacement were 19.7 ± 0.08 (range: 19.6-19.8) mm and 18.9 ± 0.2 (range: 18.4-19.5) mm in the pan and tilt directions, respectively. The gimbaled head swing was reliable for DTT. We propose a quantitative gimbaled head swing verification method for daily QA using the feature point tracking method and a web camera. Our method can quantitatively assess the gimbaled head swing for daily QA from baseline values, measured at the time of acceptance and commissioning.
['Miura|Hideharu|H|', 'Ozawa|Shuichi|S|', 'Enosaki|Tsubasa|T|', 'Kawakubo|Atsushi|A|', 'Hosono|Fumika|F|', 'Yamada|Kiyoshi|K|', 'Nagata|Yasushi|Y|']
D004867:Equipment Design D057918:Fiducial Markers D006257:Head D006801:Humans D007091:Image Processing, Computer-Assisted D021621:Imaging, Three-Dimensional D007259:Infrared Rays D009068:Movement D009369:Neoplasms D010363:Pattern Recognition, Automated D019047:Phantoms, Imaging D011785:Quality Assurance, Health Care D011879:Radiotherapy Dosage D011880:Radiotherapy Planning, Computer-Assisted D061089:Radiotherapy, Image-Guided D014057:Tomography, X-Ray Computed
quality assurance dynamic tumor tracking Vero4DRT computer processing