CTにおける信号雑音比による低コントラスト分解能の評価
Evaluation of Low Contrast Detectability using Signal-to-noise Ratio in Computed Tomography

Katsuhiro ICHIKAWA, Takanori HARA, Shinji NIWA, Isao YAMAGUCHI, Kazuya OHASHI
2007 Medical Imaging and Information Sciences  
In this paper, we proposed a new quantitative evaluation method of low-contrast detectability for computed tomography(CT)images. It is well known that the contrast-noise-ratio is not enough for CT images to evaluate the lowcontrast detectability as image quality index corresponding to various images with different frequency properties. In order to overcome this problem, we adopted a signal-to-noise ratio based on the matched filter model using low-contrast rod images (disc images)as the input
more » ... gnal. The low-contrast detectability indices obtained from this analysis method indicated good agreement with results of perceptual detectability studies. Even for the images obtained by various rod sizes, tube current settings and reconstruction kernels, this method derived appropriate index values matching the results of perceptual studies. The method proposed in this paper is very useful for CT to evaluate quantitative low-contrast image quality.
doi:10.11318/mii.24.106 fatcat:hntaffzyhvbt3fb3a4lgyhvxmi