CALIBRATION MAP, CREATION OR UPDATE METHOD OF CALIBRATION MAP, RECORDING MEDIUM INCLUDING CALIBRATION MAP, AND IRRADIATION AMOUNT VERIFICATION METHOD OF RADIOTHERAPY PLAN

• Main Authors: KAMATA SHIGEYOSHI, MIYAZAWA MASANORI
• Format: Patent
• Language: English; Japanese
• Published: 19.10.2017
• Subjects: ELECTROTHERAPY; HUMAN NECESSITIES; HYGIENE; MAGNETOTHERAPY; MEDICAL OR VETERINARY SCIENCE; RADIATION THERAPY; ULTRASOUND THERAPY

PROBLEM TO BE SOLVED: To provide a method of creating a correction map used for determining an actual irradiation dose to a photochromic film from optical density acquired by a scanner with regard to a radiation image of the transmission type photochromic film.SOLUTION: The present invention includes:(1) a step to select one non-irradiation standard film F1 and at least two irradiation standard films F2-F4 from a photochromic film group; (2) a step to form a radiation image by uniformly irradiating the whole area with mutually different irradiation doses, and with the same irradiation dose in the individual films, with regard to each irradiation standard film; (3) a step to acquire optical density data on each pixel over the whole area of each standard film under the same scanning arrangement condition in the scanner; and (4) a step to generate and record a calibration curve S of the optical density and the irradiation dose from the optical density data and the irradiation dose data of each standard film acquired in the step (3) in association with each pixel.SELECTED DRAWING: Figure 3 【課題】透過型クロミックフィルムの放射線画像について、スキャナーによって得られる光学濃度から、前記フィルムへの実際の放射線照射線量を決定するために用いる較正マップの作成方法を提供する。【解決手段】（１）クロミックフィルム群から、１枚の非照射標準フィルムＦ１と、少なくとも２枚の照射標準フィルムＦ２〜Ｆ４とを選ぶ工程、（２）各照射標準フィルムについては、相互に異なる放射線照射量であって、個々のフィルムにおいては同一の放射線照射量で全面を均一に照射して、放射線画像を形成する工程、（３）前記スキャナーにおいて、同一の走査配置条件下で、各標準フィルムの全面に亘る各画素について光学濃度データを取得する工程、及び、（４）前記工程（３）で得られた光学濃度データ及び各標準フィルムの放射線照射線量データから、光学濃度と放射線照射線量との較正曲線Ｓを、各画素のそれぞれに関連させて作成し、記録する工程を含む。【選択図】図３