X線透視画像における時系列ノイズ周波数特性

抄録

The role of the X-ray fluoroscopic image during interventional radiology (IVR) is not only the real-time dynamic image for the catheter operation but also to confirm the vascular anatomy using stored image, so that the importance increases more. For the purpose of measuring the time sequence characteristics of X-ray fluoroscopic image, we sampled the digital value of the same coordinate from each X-ray fluoroscopic image and calculated the frequency properties of the noise for the time sequence order as NPStime by performing Fourier transform on the digital value. The parameters, except k-factor which is the time sequence filter, did not influence NPStime. NPStime, which was examined in this study, showed that it is valuable for the method to analyze the time sequence noise characteristics. And, it also showed that it is possible to evaluate the time sequence image processing parameters of X-ray fluoroscopic image by NPStime. Nowadays, each manufacture of the X-ray angiographic system performs the original image processing to their own X-ray fluoroscopic images. The results of the discussion in this study could show the quantitative analysis on the frequency modulation. And it is possible to calculate NPStime by measuring the digital value of stored X-ray fluoroscopic image. The analysis by this method is also technically convenient for the time sequence noise characteristics of the X-ray fluoroscopic image.