Almén A, Tingberg A, Besjakov J, Mattsson S
Department of Radiation Physics, Malmö University Hospital, SE 205 02 Malmö, Sweden.
Eur Radiol. 2004 Sep;14(9):1561-7. doi: 10.1007/s00330-004-2320-6. Epub 2004 Apr 1.
To ensure that sufficient image quality is obtained in diagnostic radiology, the image quality of clinical radiographs has to be evaluated. We present two methods herein for evaluating antero-posterior (AP) radiographs of the lumbar spine. One was using image criteria, including six anatomical details (absolute method). In the other, the visibility of anatomical details relative to a reference radiograph was evaluated (visual grading analysis). In total, 14 technique groups were evaluated. The technique groups differed in tube voltage and detector system characteristics. Six different gradients of the H&D curves were simulated. The visual grading analysis showed larger differences in image quality compared with the absolute method. The influence on the image quality due to a variation in tube voltage was easier to detect than the influence on the image quality from the detector characteristics. The visibility of the anatomical details was significantly dependent on the location in the spine. The visual grading analysis was found to be the preferable evaluation method in studies such as the present; however, it is necessary to guide and train the observer before the evaluation is performed.
为确保在诊断放射学中获得足够的图像质量，必须对临床X光片的图像质量进行评估。我们在此介绍两种评估腰椎前后位（AP）X光片的方法。一种是使用图像标准，包括六个解剖细节（绝对法）。另一种是评估相对于参考X光片的解剖细节的可见性（视觉分级分析）。总共评估了14个技术组。这些技术组在管电压和探测器系统特性方面有所不同。模拟了H&D曲线的六种不同梯度。与绝对法相比，视觉分级分析显示出图像质量上的更大差异。管电压变化对图像质量的影响比探测器特性对图像质量的影响更容易检测到。解剖细节的可见性显著取决于脊柱中的位置。发现在当前这样的研究中，视觉分级分析是更可取的评估方法；然而，在进行评估之前有必要对观察者进行指导和培训。
