CT-AECを用いた胸部単純CTから推定した心臓CT検査における個別管電流設定の検討 / Evaluation of the Individual Tube Current Setting in Electrocardiogram-gated Cardiac Computed Tomography Estimated from Plain Chest Computed Tomography Using Computed Tomography Automatic Exposure Control
- Resource Type
- Journal Article
- Authors
- Junichi Kishimoto; Toshio Sakou; Yasutoshi Ohta; 太田 靖利; 岸本 淳一; 酒匂 敏雄
- Source
- 日本放射線技術学会雑誌 / Japanese Journal of Radiological Technology. 2013, 69(5):508
- Subject
- CT-automatic exposure control (CT-AEC)
cardiac CT
consistent image noise
individual tube current
multidetector-row computed tomography (MDCT)
- Language
- Japanese
- ISSN
- 0369-4305
1881-4883
The aim of this study was to estimate the tube current on a cardiac computed tomography (CT) from a plain chest CT using CT-automatic exposure control (CT-AEC), to obtain consistent image noise, and to optimize the scan tube current by individualizing the tube current. Sixty-five patients (Group A) underwent cardiac CT at fixed tube current. The mAs value for plain chest CT using CT-AEC (AEC value) and cardiac CT image noise were measured. The tube current needed to obtain the intended level of image noise in the cardiac CT was determined from their correlation. Another 65 patients (Group B) underwent cardiac CT with tube currents individually determined from the AEC value. Image noise was compared among Group A and B. Image noise of cardiac CT in Group B was 24.4±3.1 HU and was more uniform than in Group A (21.2±6.1 HU). The error with the desired image noise of 25 HU was lower in Group B (2.4%) than in Group A (15.2%). Individualized tube current selection based on AEC value thus provided consistent image noise and a scan tube current optimized for cardiac CT.