探讨三室限制谱成像（RSI）模型、扩散峰度成像（DKI）和扩散加权成像（DWI）在预测直肠癌Ki-67状态中的应用。共80例直肠癌患者，其中高增殖（Ki-67>50%）病例47例，低增殖（Ki-67≤50%）病例33例，均接受盆腔MRI检查。计算并比较两组之间源自 RSI（f1、f2 和 f3）、DKI（MD 和 MK）和 DWI（ADC）的参数。进行逻辑回归（LR）分析以确定独立预测因素并评估综合诊断。通过受试者工作特征曲线下面积（AUC）、DeLong分析和校准曲线分析来评估诊断性能。高增殖直肠癌患者的f1和MK值显着较高，ADC、MD、f2和f3 值高于低增殖直肠癌组（P < 0.05）。 LR 分析显示 MD、MK 和 f2 是直肠癌 Ki-67 状态的独立预测因子。此外，这三个参数的组合实现了最佳诊断效果（AUC = 0.877，敏感性 = 80.85%，特异性 = 84.85%），明显优于使用 ADC 获得的诊断效果（AUC = 0.783，Z = 2.347，P = 0.019） 、f2（AUC = 0.732、Z = 2.762、P = 0.006）和 f3（AUC = 0.700、Z = 3.071、P = 0.002）。联合诊断在基于1000个bootstrap样本的内部验证分析中也表现出良好的性能（AUC = 0.859），而校准曲线表明联合诊断提供了良好的稳定性。RSI、DKI和DWI可以有效地区分高危患者。和低增殖直肠癌。此外，MD、MK 和 f2 成像参数可能是一种新颖且有前途的组合生物标志物，用于检查直肠癌 Ki-67 状态。版权所有 © 2024 大学放射科医生协会。由爱思唯尔公司出版。保留所有权利。

To investigate the application of the three-compartment restriction spectrum imaging (RSI) model, diffusion kurtosis imaging (DKI), and diffusion-weighted imaging (DWI) in predicting Ki-67 status in rectal carcinoma.A total of 80 rectal carcinoma patients, including 47 high-proliferation (Ki-67 > 50%) cases and 33 low-proliferation (Ki-67 ≤ 50%) cases, underwent pelvic MRI were enrolled. Parameters derived from RSI (f1, f2, and f3), DKI (MD and MK), and DWI (ADC) were calculated and compared between the two groups. Logistic regression (LR) analysis was conducted to identify independent predictors and assess combined diagnosis. Area under the receiver operating characteristic curve (AUC), DeLong analysis, and calibration curve analyses were performed to evaluate diagnostic performance.The patients with high-proliferation rectal carcinoma exhibited significantly higher f1 and MK values and significantly lower ADC, MD, f2, and f3 values than those with low-proliferation rectal carcinoma (P < 0.05). LR analysis showed that MD, MK, and f2 were independent predictors for Ki-67 status in rectal carcinoma. Moreover, the combination of these three parameters achieved an optimal diagnostic efficacy (AUC = 0.877, sensitivity = 80.85%, specificity = 84.85%) that was significantly better than that obtained using ADC (AUC = 0.783, Z = 2.347, P = 0.019), f2 (AUC = 0.732, Z = 2.762, P = 0.006), and f3 (AUC = 0.700, Z = 3.071, P = 0.002). The combined diagnosis also showed good performance (AUC = 0.859) in the internal validation analysis based on 1000 bootstrap samples, while the calibration curve demonstrated that the combined diagnosis provided good stability.RSI, DKI, and DWI can effectively differentiate between patients with high- and low-proliferation rectal carcinoma. Furthermore, the MD, MK, and f2 imaging parameters may be a novel and promising combination biomarker for examining Ki-67 status in rectal carcinoma.Copyright © 2024 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.