Baidya Kayal Esha, Kandasamy Devasenathipathy, Yadav Richa, Khare Kedar, Bakhshi Sameer, Sharma Raju, Mehndiratta Amit
From the Centre for Biomedical Engineering, Indian Institute of Technology Delhi, New Delhi, India.
Department of RadioDiagnosis, All India Institute of Medical Sciences.
J Comput Assist Tomogr. 2024;48(2):263-272. doi: 10.1097/RCT.0000000000001540. Epub 2023 Nov 24.
The objective was to assess qualitative interpretability and quantitative precision and reproducibility of intravoxel incoherent motion ( IVIM) parametric images evaluated using novel IVIM analysis methods for diagnostic accuracy.
Intravoxel incoherent motion datasets of 55 patients (male/female = 41:14; age = 17.8 ± 5.5 years) with histopathology-proven osteosarcoma were analyzed. Intravoxel incoherent motion parameters-diffusion coefficient ( D ), perfusion fraction ( f ), and perfusion coefficient ( D* )-were estimated using 5 IVIM analysis methods-(i) biexponential (BE) model, (ii) BE-segmented fitting 2-parameter (BESeg-2), (iii) BE-segmented fitting 1-parameter (BESeg-1), (iv) BE model with total variation penalty function (BE + TV), and (v) BE model with Huber penalty function (BE + HPF). Qualitative scoring in a 5-point Likert scale (uninterpretable: 1; poor: 2; fair: 3; good: 4; excellent: 5) was performed by 2 radiologists for 4 criteria: (a) tumor shape and margin, (b) morphologic correlation, (c) noise suppression, and (d) overall interpretability. Interobserver agreement was evaluated using Spearman rank-order correlation ( rs ). Precision and reproducibility were evaluated using within-subject coefficient of variation (wCV) and between-subject coefficient of variation (bCV).
BE + TV and BE + HPF produced significantly ( P < 10 -3 ) higher qualitative scores for D (fair-good [3.3-3.8]) than BE (poor [2.3]) and for D* (poor-fair [2.2-2.7]) and f (fair-good [3.2-3.8]) than BE, BESeg-2, and BESeg-1 ( D* : uninterpretable-poor [1.3-1.9] and f : poor-fair [1.5-3]). Interobserver agreement for qualitative scoring was rs = 0.48-0.59, P < 0.009. BE + TV and BE + HPF showed significantly ( P < 0.05) improved reproducibility in estimating D (wCV: 24%-31%, bCV: 21%-31% improvement) than the BE method and D* (wCV: 4%-19%, bCV: 5%-19% improvement) and f (wCV: 25%-49%, bCV: 25%-47% improvement) than BE, BESeg-2, and BESeg-1 methods.
BE + TV and BE + HPF demonstrated qualitatively and quantitatively improved IVIM parameter estimation and may be considered for clinical use further.
本研究旨在评估使用新型体素内不相干运动（IVIM）分析方法评估的IVIM参数图像在诊断准确性方面的定性可解释性、定量精度和可重复性。
分析了55例经组织病理学证实为骨肉瘤患者（男/女 = 41:14；年龄 = 17.8 ± 5.5岁）的体素内不相干运动数据集。使用5种IVIM分析方法估计体素内不相干运动参数——扩散系数（D）、灌注分数（f）和灌注系数（D*）：（i）双指数（BE）模型，（ii）BE分段拟合双参数（BESeg-2），（iii）BE分段拟合单参数（BESeg-1），（iv）具有总变分惩罚函数的BE模型（BE + TV），以及（v）具有Huber惩罚函数的BE模型（BE + HPF）。两名放射科医生根据4项标准采用5分李克特量表进行定性评分（无法解释：1分；差：2分；一般：3分；好：4分；优秀：5分）：（a）肿瘤形状和边缘，（b）形态学相关性，（c）噪声抑制，以及（d）整体可解释性。使用Spearman等级相关（rs）评估观察者间的一致性。使用受试者内变异系数（wCV）和受试者间变异系数（bCV）评估精度和可重复性。
与BE模型（差[2.3]）相比，BE + TV和BE + HPF对D的定性评分显著更高（P < 10-3）（一般-好[3.3 - 3.8]），与BE、BESeg-2和BESeg-1相比，对D*（差-一般[2.2 - 2.7]）和f（一般-好[3.2 - 3.8]）的定性评分更高（D*：无法解释-差[1.3 - 1.9]，f：差-一般[1.5 - 3]）。定性评分的观察者间一致性为rs = 0.48 - 0.59，P < 0.009。与BE方法相比，BE + TV和BE + HPF在估计D时的可重复性显著提高（P < 0.05）（wCV：提高24% - 31%，bCV：提高21% - 31%），与BE、BESeg-2和BESeg-1方法相比，在估计D*（wCV：提高4% - 19%，bCV：提高5% - 19%）和f（wCV：提高25% - 49%，bCV：提高25% - 47%）时的可重复性也显著提高。
BE + TV和BE + HPF在定性和定量方面均改善了IVIM参数估计，可能值得进一步考虑用于临床。
