本研究旨在评估直肠癌 (RC) 患者多 b 值扩散加权成像 (DWI) 的图像质量和区域淋巴结转移 (LNM)。这项回顾性研究纳入了 199 名接受过多次检查的 RC 患者。 b 值 DWI。对 DWIb1000、DWIb2000 和 DWIb3000 进行图像质量的主观（五点李克特量表）和客观评估。患者被随机分为训练组 (n = 140) 或验证组 (n = 59)。分别在 ADC 图（b = 0、1000 s/mm2）、DWIb1000、DWIb2000 和 DWIb3000 上提取全体积肿瘤内的放射组学特征。使用逻辑回归分析开发了基于所选特征的五种预测模型。通过受试者工作特征曲线、校准和决策曲线分析 (DCA) 评估放射组学模型的性能。肿瘤的平均信号强度 (SItumor)、信噪比 (SNR) 以及伪影和解剖可微性随着 b 值的增加，分数逐渐降低。然而，DWIb2000 的噪声对比 (CNR) 优于 DWIb1000 和 DWIb3000（分别为 4.58±0.86、3.82±0.77、4.18±0.84、p<0.001）。 DWIb2000的总体图像质量得分高于DWIb3000（p < 0.001），并且DWIb1000和DWIb2000之间没有显着差异（p = 0.059）。基于DWIb2000的放射组学模型的曲线下面积（AUC）值（0.728）高于传统ADC图（0.690）、DWIb1000（0.699）和DWIb3000（0.707），但逊于多b值DWI（0.739） ）在预测 LNM 中。在 RC 中，DWIb2000 比 DWIb1000 和 DWIb3000 提供更好的病灶明显性和 LNM 预测。DWIb2000 提供令人满意的病灶可视化。基于DWIb2000的放射组学特征可用于术前预测直肠癌区域淋巴结转移，从而有利于分层治疗策略。直肠癌需要进行淋巴结分期来确定最佳治疗方案。 DWIb2000 提供卓越的对比噪声比和病变显着性，其衍生的放射组学可以最好地预测淋巴结转移。 DWIb2000 可能被推荐作为直肠 MRI 方案中的最佳 b 值。© 2024。作者获得欧洲放射学会的独家许可。

This study aims to evaluate image quality and regional lymph node metastasis (LNM) in patients with rectal cancer (RC) on multi-b-value diffusion-weighted imaging (DWI).This retrospective study included 199 patients with RC who had undergone multi-b-value DWI. Subjective (five-point Likert scale) and objective assessments of quality images were performed on DWIb1000, DWIb2000, and DWIb3000. Patients were randomly divided into a training (n = 140) or validation cohort (n = 59). Radiomics features were extracted within the whole volume tumor on ADC maps (b = 0, 1000 s/mm2), DWIb1000, DWIb2000, and DWIb3000, respectively. Five prediction models based on selected features were developed using logistic regression analysis. The performance of radiomics models was evaluated with a receiver operating characteristic curve, calibration, and decision curve analysis (DCA).The mean signal intensity of the tumor (SItumor), signal-to-noise ratio (SNR), and artifact and anatomic differentiability score gradually were decreased as the b-value increased. However, the contrast-to-noise (CNR) on DWIb2000 was superior to those of DWIb1000 and DWIb3000 (4.58 ± 0.86, 3.82 ± 0.77, 4.18 ± 0.84, p < 0.001, respectively). The overall image quality score of DWIb2000 was higher than that of DWIb3000 (p < 0.001) and showed no significant difference between DWIb1000 and DWIb2000 (p = 0.059). The area under curve (AUC) value of the radiomics model based on DWIb2000 (0.728) was higher than conventional ADC maps (0.690), DWIb1000 (0.699), and DWIb3000 (0.707), but inferior to multi-b-value DWI (0.739) in predicting LNM.DWIb2000 provides better lesion conspicuity and LNM prediction than DWIb1000 and DWIb3000 in RC.DWIb2000 offers satisfactory visualization of lesions. Radiomics features based on DWIb2000 can be applied for preoperatively predicting regional lymph node metastasis in rectal cancer, thereby benefiting the stratified treatment strategy.Lymph node staging is required to determine the best treatment plan for rectal cancer. DWIb2000 provides superior contrast-to-noise ratio and lesion conspicuity and its derived radiomics best predict lymph node metastasis. DWIb2000 may be recommended as the optimal b-value in rectal MRI protocol.© 2024. The Author(s), under exclusive licence to European Society of Radiology.