Department of Medical Imaging, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
Department of Medical Imaging, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
Skeletal Radiol. 2022 Sep;51(9):1853-1863. doi: 10.1007/s00256-022-04040-6. Epub 2022 Mar 26.
To evaluate the performance and reliability of the single-energy metal artifact reduction (SEMAR) algorithm in patients with different orthopedic hardware at the hips.
A total of 153 patients with hip instrumentation who had undergone CT with adaptive iterative dose reduction (AIDR) 3D and SEMAR algorithms between February 2015 and October 2019 were included retrospectively. Patients were divided into 5 groups by the hardware type. Two readers with 21 and 13 years of experience blindly reviewed all image sets and graded the extent of artifacts and imaging quality using 5-point scales. To evaluate reliability, the mean densities and image noises were measured at the urinary bladder, veins, and fat in images with artifacts and the reference images.
No significant differences were found in the mean densities of the urinary bladder, veins, and fat between the SEMAR images with artifacts (7.57 ± 9.49, 40.29 ± 23.07, 86.78 ± 38.34) and the reference images (7.77 ± 6.2, 40.27 ± 8.66, 89.10 ± 20.70) (P = .860, .994, .392). Image noises of the urinary bladder in the SEMAR images with artifacts (14.25 ± 4.50) and the SEMAR reference images (9.69 ± 1.29) were significantly higher than those in the AIDR 3D reference images (9.11 ± 1.12) (P < .001; P < .001). All AIDR 3D images were non-diagnostic (overall quality ≤ 3) and less than a quarter of the SEMAR images were non-diagnostic (16.7-23.7%), mainly in patients with prostheses [reader 1: 91.7% (22/24); reader 2: 92.6% (25/27)].
The SEMAR algorithm significantly reduces metal artifacts in CT images, more in patients with internal fixations than in patients with prostheses, and provides reliable attenuation of soft tissues.
评估单能量金属伪影降低（SEMAR）算法在髋关节不同骨科内固定物患者中的性能和可靠性。
回顾性分析 2015 年 2 月至 2019 年 10 月间 153 例接受自适应迭代剂量降低（AIDR）3D 和 SEMAR 算法 CT 扫描的髋关节内固定患者。根据内固定物类型将患者分为 5 组。两位具有 21 年和 13 年经验的读者分别对所有图像进行盲法评估，并使用 5 分制评估图像伪影程度和图像质量。为了评估可靠性，在有伪影的 SEMAR 图像和参考图像上测量膀胱、静脉和脂肪的平均密度和图像噪声。
SEMAR 图像中带有伪影的膀胱、静脉和脂肪的平均密度（7.57±9.49、40.29±23.07、86.78±38.34）与参考图像（7.77±6.2、40.27±8.66、89.10±20.70）相比，无统计学差异（P=0.860、0.994、0.392）。SEMAR 图像中带有伪影的膀胱图像噪声（14.25±4.50）和 SEMAR 参考图像（9.69±1.29）明显高于 AIDR 3D 参考图像（9.11±1.12）（P<0.001；P<0.001）。所有 AIDR 3D 图像均为非诊断性（总体质量≤3），不到四分之一的 SEMAR 图像为非诊断性（16.7%-23.7%），主要见于假体患者（读者 1：91.7%（22/24）；读者 2：92.6%（25/27））。
SEMAR 算法可显著降低 CT 图像中的金属伪影，对于内固定患者的降低效果优于假体患者，且能可靠衰减软组织。
