Neroladaki Angeliki, Martin Steve Philippe, Bagetakos Ilias, Botsikas Diomidis, Hamard Marion, Montet Xavier, Boudabbous Sana
Radiology Department, Geneva University Hospital, Genève, Switzerland.
Medicine (Baltimore). 2019 Feb;98(6):e14341. doi: 10.1097/MD.0000000000014341.
To evaluate iterative metal artifact reduction (iMAR) technique in images data of hip prosthesis on computed tomography (CT) and the added value of advanced modeled iterative reconstruction (ADMIRE) compared with standard filtered back projection (FBP).Twenty-eight patients addressed to CT examinations for hip prosthesis were included prospectively. Images were reconstructed with iMAR algorithm in addition to FBP and ADMIRE techniques. Measuring image noise assessed objective image quality and attenuation values with standardized region of interest (ROI) in 4 predefined anatomical structures (gluteus medius and rectus femoris muscles, inferior and anterior abdominal fat, and femoral vessels when contrast media was present). Subjective image quality was graded on a 5-point Likert scale, taking into account the size of artifacts, the metal-bone interface and the conspicuity of pelvic organs, and the diagnostic confidence.Improvement in overall image quality was statistically significant using iMAR (P<.001) compared with ADMIRE and FBP. ADMIRE did not show any impact in image noise, attenuation value, or global quality image. iMAR showed a significant decrease in image noise in all ROIs (Hounsfield Unit) as compared with FBP and ADMIRE. Interobserver agreement was high in all reconstructions (FBP, FBP+iMAR, ADMIRE, and ADMIRE + iMAR) more than 0.8. iMAR reconstructions showed emergence of new artifacts in bone-metal interface.iMAR algorithm allows a significant reduction of metal artifacts on CT images with unilateral or bilateral prostheses without additional value of ADMIRE. It improves the analysis of surrounding tissue but potentially generates new artifacts in bone-metal interface.
评估迭代金属伪影减少(iMAR)技术在计算机断层扫描(CT)髋关节假体图像数据中的应用,以及与标准滤波反投影(FBP)相比,高级模型迭代重建(ADMIRE)的附加价值。前瞻性纳入28例因髋关节假体接受CT检查的患者。除了FBP和ADMIRE技术外,还用iMAR算法重建图像。通过在4个预定义解剖结构(臀中肌和股直肌、下腹部和前腹部脂肪以及存在造影剂时的股血管)中使用标准化感兴趣区(ROI)测量图像噪声来评估客观图像质量和衰减值。主观图像质量采用5分李克特量表进行分级,同时考虑伪影大小、金属-骨界面以及盆腔器官的清晰度和诊断置信度。与ADMIRE和FBP相比,使用iMAR时整体图像质量的改善具有统计学意义(P<0.001)。ADMIRE在图像噪声、衰减值或整体质量图像方面未显示任何影响。与FBP和ADMIRE相比,iMAR在所有ROI(亨氏单位)中的图像噪声均显著降低。所有重建(FBP、FBP+iMAR、ADMIRE和ADMIRE+iMAR)的观察者间一致性均较高,超过0.8。iMAR重建在骨-金属界面出现了新的伪影。iMAR算法可显著减少单侧或双侧假体CT图像上的金属伪影,且ADMIRE无附加价值。它改善了对周围组织的分析,但可能在骨-金属界面产生新的伪影。