OBJECTIVE:In this study, we present an appropriate angle of incidence to reduce the distortions in images of L4 and L5 during a general anteroposterior radiograph examination. METHOD:We selected 170 patients who had normal radiological findings among those who underwent anteroposterior and lateralexamination for lumbar vertebrae. An optimum angle of incidence wa suggested through the statistical analysis by measuring the lumbar lordosis angle and the intervertebral disc angle in these 170 patients. RESULT:We suggested the incident angle (10.28°) of L4 and the incident angle (23.49°) of L5. We compared the distorted area ratios when the incident angle was 0°, 10°, and 23.5° using the ATOM® phantom. The ratio for the L4 decreased from 14.90% to 12.11% and that of the L5 decreased from 15.25% to 13.72% after applying the angle of incidence. We determined the incident angle (9.34°) of L4 and (21.26°) of L5 below 30° of LLA. Thus, we determined the incident angle (11.21°) of L4 and (25.73°) of L5 above 30° of LLA. CONCLUSION:When you apply the optimum angle of incidence, the distortion of image was minimized and an image between the joints adjacent to the anteroposterior vertebral image with an accurate structure was obtained. As a result, we were able to improve the quality of the image and enhance diagnostic information.

中文翻译：

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根据最佳入射角提高椎体一般前后位X线图像质量

目的：在这项研究中，我们提出了一个适当的入射角，以减少常规前后位 X 光检查期间 L4 和 L5 图像的失真。方法：我们在接受腰椎正位和侧位检查的患者中选择了 170 名放射学结果正常的患者。通过测量这170例患者的腰椎前凸角和椎间盘角的统计分析，提出了最佳的入射角。结果：我们建议L4的入射角（10.28°）和L5的入射角（23.49°）。我们使用 ATOM® 体模比较了入射角为 0°、10° 和 23.5° 时的畸变面积比。应用入射角后，L4 的比率从 14.90% 下降到 12.11%，L5 的比率从 15.25% 下降到 13.72%。我们在 LLA 的 30° 以下确定了 L4 的入射角 (9.34°) 和 L5 的入射角 (21.26°)。因此，我们确定了 L4 的入射角 (11.21°) 和 LLA 30° 以上的 L5 的入射角 (25.73°)。结论：当应用最佳入射角时，图像失真最小，获得了结构准确的前后椎体图像相邻关节之间的图像。因此，我们能够提高图像质量并增强诊断信息。最大限度地减少了图像失真，获得了结构准确的前后椎体图像相邻关节之间的图像。因此，我们能够提高图像质量并增强诊断信息。最大限度地减少了图像失真，获得了结构准确的前后椎体图像相邻关节之间的图像。因此，我们能够提高图像质量并增强诊断信息。