Physical Imaging Properties Research Articles

胸部撮影のための新しい増感紙-フィルム系の画像特性

胸部撮影のための新しい増感紙-フィルム系の画像特性

276 新オルソシステムの物理特性と臨床評価

276 新オルソシステムの物理特性と臨床評価

270 胸部専用Systemの物理特性と臨床評価について : EX, AD Systemの比較検討

270 胸部専用Systemの物理特性と臨床評価について : EX, AD Systemの比較検討

Physical evaluation of computed radiography as a mammographic X-ray imaging system

The physical imaging properties of a computed radiography (CR) system operating under mammographic exposure conditions have been measured. These measurements include modulation transfer function (MTF), sensitometric response and noise power spectrum (NPS). These figures were used to derive signal-to-noise ratio (SNR) descriptors of the system performance. The same measures were derived for a mammographic film-screen system. The SNR properties of the CR system indicate superior low frequency performance over a wider dynamic range than the film-screen system. The spatial frequency dependent SNR properties of the CR system are, however, limited. The results of a psychophysical test support the results obtained from physical measurements. These results indicate that despite its limited sharpness, details of dimensions relevant to diagnosis in mammography (circular details 0.25 mm diameter to represent microcalcifications and 3 mm diameter to represent small masses) are reproduced using CR with SNRs which are at least comparable with those of a mammographic film-screen system.

384. 新しい増感紙-フィルム系の物理特性と臨床応用(画像工学 新オルソシステム-2)

384. 新しい増感紙-フィルム系の物理特性と臨床応用(画像工学 新オルソシステム-2)

174. 胸部撮影における非対称増感紙-フィルム系の画像特性と臨床応用(第 49 回総会学術大会一般研究発表予稿)

174. 胸部撮影における非対称増感紙-フィルム系の画像特性と臨床応用(第 49 回総会学術大会一般研究発表予稿)

174. 胸部撮影における非対称増感紙 : フィルム系の画像特性と臨床応用(画像工学-4 非対称系画質評価 (2))

174. 胸部撮影における非対称増感紙 : フィルム系の画像特性と臨床応用(画像工学-4 非対称系画質評価 (2))

Theoretical limitations of tumor imaging

The question of limitations of tumor imaging needs to be examined against the characteristics of current medical imaging systems. Moreover, the examination needs to be carried out against the backdrop of physical imaging properties of the imaging systems, as well as the physiological and chemical aspects of the underlying biological signals (tumors) and background (nontumor) areas. In particular, the important possibilities for enhanced image performance using labeled monoclonal antibodies need to be explored.

Controlled single-blind clinical evaluation of low-dose mammographic screen--film systems.

The ability of five low-dose mammographic screen--film systems to portray normal and abnormal breast structures was evaluated in parallel with a study of physical image properties. Single-blind evaluations of the visibility of normal breast architecture, mass lesions, and calcifications were made on the mammograms of 100 patients radiographed with each of the systems. There was increased noise and slightly poorer resolution for the faster recording systems, but there was no difference in final diagnostic impressions among the five systems. These results suggest that the faster systems will result in substantial dose reduction without sacrificing diagnostic accuracy.