Effect of Heat on Image Plates in Computed Radiography Systems

Purpose The sensitivity of computed radiographic (CR) image plates to ionizing and/or nonionizing radiation such as light, heat, and scatter radiation have been known to cause effects such as electronic noise and to degrade image quality. The purpose of this study was to investigate the effects of image plate storage temperature on dark noise. Method Image plates from Fuji and AGFA CR systems were stored at various room temperatures for 5-hour durations and then processed using the respective systems. The average pixel value in several regions of interest in the resultant images were used an indication of dark noise. The variation in the average pixel values was used to calculate image noise levels. Results Image plates of the Fuji system only showed significant increase in dark noise and image noise levels when the temperature exceeded 40°C. The image plates of the AGFA system showed increases in both quantities at all temperatures. Conclusion It is recommended that storage temperatures of image plates be kept below 35°C to minimize dark noise effects.