Bachl Maximilian, Skwierawska Dominika, Hadler Dominique, Schreiter Hannes, Uder Michael, Janka Rolf, Laun Frederik B, Bickelhaupt Sebastian
Institute of Radiology, Uniklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
Invest Radiol. 2025 Sep 1;60(9):592-601. doi: 10.1097/RLI.0000000000001171.
Recent advances in high-performance gradient technology have enabled shorter echo times (TEs) for diffusion-weighted prostate MRI. Short TE may improve the conspicuity of the usually T 2 hypointense lesions but may also influence the diagnostic performance of the apparent diffusion coefficient (ADC) due to a changed weighting of subcompartments, including prostate fluid and tissues. The purpose of this study was to evaluate the influence of TE on prostate diffusion-weighted images with respect to lesion conspicuity and diagnostic performance of the ADC.
This institutional review board-approved prospective monocentric study included n = 55 (mean age 69 ± 9 years) patients undergoing clinically indicated prostate MRI on two 3 T MRI scanners with high-performance gradients. Diffusion-weighted imaging (DWI) was performed with an echo-planar sequence at 2 different TEs, 41 ms and 70 ms, with b-values of 50 s/mm 2 and 800 s/mm 2 . Computed DWI was generated for a b-value of 1400 s/mm 2 . The lesion conspicuity and image quality were rated by 3 independent readers with a 5-point Likert scale and tested with the Wilcoxon rank sum test. Lesion ADCs were recorded, and their ability to detect significant lesions (Gleason score >6) was assessed with a receiver operator curve analysis.
Among the participants, n = 24 had clinically significant prostate cancer. The image quality at b = 1400 s/mm 2 was rated significantly higher at TE = 41 ms than at TE = 70 ms (mean Likert score ± standard deviation for TE = 41 ms vs TE = 70 ms: R1: 4.06 ± 0.68 vs 3.02 ± 0.59; R2: 4.09 ± 0.82 vs 3.26 ± 0.67; R3: 4.16 ± 0.71 vs 3.18 ± 0.70; for all P 's < 0.001). The lesion conspicuity at b = 1400 s/mm 2 was rated higher at TE = 41 ms than at TE = 70 ms (mean Likert score ± standard deviation for TE = 41 ms vs TE = 70 ms: R1: 4.55 ± 0.66 vs 4.46 ± 0.72, P = 0.17; R2: 4.64 ± 0.59 vs 4.53 ± 0.63, P = 0.03; R3: 4.53 ± 0.66 vs 4.28 ± 0.80, P = 0.01). However, the ADC-based area under the curve for lesion characterization decreased from 0.80 at TE = 70 ms to 0.70 at TE = 41 ms ( P = 0.07).
Shortening TE to 41 ms in prostate DWI increases lesion conspicuity on high b-value images; however, it negatively impacts the diagnostic performance of the ADC.
高性能梯度技术的最新进展使得前列腺扩散加权磁共振成像（MRI）能够实现更短的回波时间（TE）。短TE可能会提高通常呈T2低信号病变的清晰度，但也可能由于包括前列腺液和组织在内的亚成分权重变化而影响表观扩散系数（ADC）的诊断性能。本研究的目的是评估TE对前列腺扩散加权图像上病变清晰度和ADC诊断性能的影响。
本前瞻性单中心研究经机构审查委员会批准，纳入了n = 55例（平均年龄69±9岁）在两台配备高性能梯度的3T MRI扫描仪上接受临床指征前列腺MRI检查的患者。采用回波平面序列在2个不同的TE（41 ms和70 ms）下进行扩散加权成像（DWI），b值分别为50 s/mm²和800 s/mm²。生成b值为1400 s/mm²的计算DWI。由3名独立阅片者采用5分李克特量表对病变清晰度和图像质量进行评分，并采用Wilcoxon秩和检验进行测试。记录病变的ADC值，并通过受试者操作特征曲线分析评估其检测显著病变（Gleason评分>6）的能力。
在参与者中，n = 24例患有临床显著前列腺癌。b = 1400 s/mm²时，TE = 41 ms的图像质量评分显著高于TE = 70 ms（TE = 41 ms与TE = 70 ms的平均李克特评分±标准差：R1：4.06±0.68对3.02±0.59；R2：4.09±0.82对3.26±0.67；R3：4.16±0.71对3.18±0.70；所有P值<0.001）。b = 1400 s/mm²时，TE = 41 ms的病变清晰度评分高于TE = 70 ms（TE = 41 ms与TE = 70 ms的平均李克特评分±标准差：R1：4.55±0.66对4.46±0.72，P = 0.17；R2：4.64±0.59对4.53±0.63，P = 0.03；R3：4.53±0.66对4.28±0.80，P = 0.01）。然而，基于ADC的病变特征曲线下面积从TE = 70 ms时的0.80降至TE = 41 ms时的0.70（P = 0.07）。
在前列腺DWI中将TE缩短至41 ms可提高高b值图像上的病变清晰度；然而，这会对ADC的诊断性能产生负面影响。
