[Evaluation of routine examinations using automatic scan technique optimization for X-CT].
Auto mA is a function that automatically controls tube current so as to stabilize image quality. To determine the applicability of this function to routine inspection work, an evaluation was carried out by two doctors in the department of radiology and five technicians in the department of diagnostic radiology using home-made phantoms and phantoms for low contrast resolution determination. The phantom experiment provided an almost constant level of SD values in each Auto mA mode tested, independent of scanning type, slice thickness, and phantom shape. In addition, nearly stable low contrast resolution was attained independent of phantom shape, e.g., circle and ellipse. The results suggest that stable image quality is available in the clinical stage for individual patients and regions, independent of the size and shape of targets. As for the evaluation of clinical images, the image quality requested by clinical operations at our hospital was attained even in the low dose mode that provides the lowest dose level. In addition, for variations in tube current values for photographing in individual regions, both sustained image uniformity and exposure reduction were found to be satisfactory in comparison with constant tube current.
Nakajima
Masatoshi
M
Department of Radiology, Kanagawa Prefecture Agricultural Cooperative Welfare Federation-Sagamihara Kyodo Hospital, Japan.
D006801:Humans; D019047:Phantoms, Imaging; D014057:Tomography, X-Ray Computed / Q000379:methods*