Image Quality of an Intraoral Storage Phosphor Imaging System for Crinical Setting

随着影像诊断信息的数字化，各种数字化成像医疗设备应运而生。Digora是作为一种数字成像系统开发的，其中成像板(IP)被用作成像传感器来获得口腔图像。由于这些数字成像系统都使用CRT图像，因此我们使用Digora系统对CRT图像进行临床影像诊断，寻找最佳的IP，然后尝试建立数字成像系统在牙科领域的评价参数。(1)通过放大X线片等检查数字成像系统的特性，以确定其有效性。(2)将Digora的图像格式转换为CR的胶片输出，以检验胶片图像和CRT图像的准确诊断能力。(3)以下颌骨模型为研究对象，比较CRT图像、…图像对正常下颌骨解剖结构的识别能力。更多ES，以及使用Digora获得的电影图像。结果显示，3种图像之间无明显差异。(4)3种图像对近表面龋病的检出能力无明显差异。(5)3种图像对松质骨脱钙的诊断能力无差异。(6)从(2)、(3)、(4)和(5)中描述的结果显示，使用CRT图像可以准确地诊断口腔疾病，这表明没有必要输出胶片。(7)CRT图像与胶片图像对临床病例(龋齿、根尖囊肿、根尖周炎、边缘牙周炎)的诊断能力比较，差异无统计学意义。(8)比较Digora系统中不同类型IP(HR为Digora；ST为普通摄影；UR为电子显微镜摄影)的照射时间时，HR可作出诊断，而照射时间缩短至D速片的1/4，表明使用HR可减少剂量。(9)当检查3种IP的物理成像特性时，UR可获得高MTF，而HR在低剂量时可获得满意的NEQ。(10)综合评价(8)和(9)中的结果，确定了Digora系统临床病例的最佳IP为HR.论证了评价数字影像系统中图像传感器和输出图像的重要性，并建立了评价数字影像系统的参数。较少

With the digitalization of information concerning imaging diagnosis, many medical devices for digital imaging have been developed. Digora was developed as a digital imaging system in which an imaging plate (IP) is used as an imaging sensor to obtain images of the oral. Since CRT images are used in such digital imaging systems, we made clinical imaging diagnoses based on CRT images using a Digora system to find an optimal IP,and then we attempted to establish parameters for the evaluation of digital imaging systems in the field of dentistry.(1) Characteristics of the digital imaging system with IP were examined by enlargement radiography, etc.to determine its usefulness. (2) The imaging format of Digora was converted to the film output for CR,in order to examine the ability of film images in making accurate diagnosis and that of CRT images. (3) The ability of recognizing normal mandibular anatomy was visually compared using a mandibular phantom between CRT images, conventional film imag … More es, and film images obtained with Digora. As a result, no differences were observed between those 3 kinds of images. (4) The ability to detect proximal surface caries did not differ between the 3 kinds of images. (5) The ability to diagnose decalcification of spongy bone did not differ neither between the 3 kinds of images. (6) From the findings described in (2), (3), (4), and (5), it was revealed that oral diseases could be accurately diagnosed using CRT images, indicating the unnecessity of film output. (7) When the ability to diagnose clinical cases (caries, radicular cyst, apical periodontitis, and marginal periodontitis) was compared between CRT images and film images, no difference was observed. (8) When irradiation time was compared among different types of IP in the Digora system (HR for Digora ; ST for general radiography ; UR for electron microscopic radiography), diagnosis could be made using a HR while an irradiation time was shortened to 1/4 that of D speed film, indicating that a dose could be reduced by using a HR.(9) When physical imaging properties of 3 types of IP were examined, a high MTF was obtained with UR whereas HR showed a satisfactory NEQ at a low dose. (10) As overall evaluation on the findings obtained in (8) and (9), an optimal IP in the Digora system for clinical cases was determined to be HR.We demonstrated the significance of evaluation of image sensors and output images in digital imaging systems and established parameters for the evaluation of digital imaging systems. Less