■合成磁共振成像(MRI)可以提供有关固有组织特性的定量信息,并在单次扫描中同时合成量身定制的对比加权图像。本研究旨在探讨膀胱肿瘤综合MRI的临床可行性。
■这项回顾性研究共纳入47例(男性37例;平均年龄:66±10岁)术后病理证实为膀胱乳头状尿路上皮肿瘤。在3T下对合成MRI进行了2维(2D)多动态多回波脉冲序列。整体图像质量,病变显著,对比度分辨率,精细解剖结构的分辨率,运动伪影,模糊,2名放射科医生使用5点Likert量表进行定性分析,对图像的颗粒性进行了主观评估。信号强度比(SIR),信噪比(SNR),和对比噪声比(CNR)进行定量分析。线性加权Kappa,威尔科克森的符号秩检验,采用Mann-WhitneyU检验进行统计分析。
■观察者之间的一致性非常好(κ值:0.607-1)。合成T1加权(syn-T1w)和合成T2加权(syn-T2w)图像在大多数主观方面获得4分,与传统图像相比相对较小。syn-T1w的SIR和SNR明显高于con-T1w图像(SIR2.37±0.86vs.1.47±0.20,P<0.001;SNR21.83±9.43vs.14.81±3.30,P<0.001)。syn-T2w和常规T2加权(con-T2w)图像之间的SIR没有发现差异,而syn-T2w的SNR明显较低(8.79±4.06vs.26.49±6.80,P<0.001)。此外,合成图像的CNR明显低于常规图像(T1w1.41±0.72vs.2.68±1.04;T2w1.40±0.87vs.4.03±1.55,均P<0.001)。
■合成MRI在膀胱肿瘤中产生具有诊断上可接受的图像质量的形态磁共振(MR)图像,特别是T1加权图像,肿瘤相对于尿液的图像对比度高。合成MRI需要进一步的技术改进以降低噪声。结合T1、T2和质子密度(PD)定量数据,合成MRI在膀胱肿瘤中具有临床应用潜力。
UNASSIGNED: Synthetic magnetic resonance imaging (MRI) can provide quantitative information about inherent tissue properties and synthesize tailored contrast-weighted images simultaneously in a single scan. This
study aimed to investigate the clinical feasibility of synthetic MRI in bladder tumors.
UNASSIGNED: A total of 47 patients (37 males; mean age: 66±10 years old) with postoperative pathology-confirmed papillary urothelial neoplasms of the bladder were enrolled in this retrospective
study. A 2-dimensional (2D) multi-dynamic multi-echo pulse sequence was performed for synthetic MRI at 3T. The overall image quality, lesion conspicuity, contrast resolution, resolution of subtle anatomic structures, motion artifact, blurring, and graininess of images were subjectively evaluated by 2 radiologists independently using a 5-point Likert scale for qualitative analysis. The signal intensity ratio (SIR), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured for quantitative analysis. Linear weighted Kappa, Wilcoxon\'s signed-rank test, and the Mann-Whitney U-test were used for statistical analysis.
UNASSIGNED: The interobserver consistency was excellent (κ values: 0.607-1). Synthetic T1-weighted (syn-T1w) and synthetic T2-weighted (syn-T2w) images obtained scores of 4 in most subjective terms, which were relatively smaller than those of conventional images. The SIR and SNR of syn-T1w were significantly higher than those of con-T1w images (SIR 2.37±0.86 vs. 1.47±0.20, P<0.001; SNR 21.83±9.43 vs. 14.81±3.30, P<0.001). No difference was found in SIR between syn-T2w and conventional T2-weighted (con-T2w) images, whereas the SNR of the syn-T2w was significantly lower (8.79±4.06 vs. 26.49±6.80, P<0.001). Additionally, the CNR of synthetic images was significantly lower than that of conventional images (T1w 1.41±0.72 vs. 2.68±1.04; T2w 1.40±0.87 vs. 4.03±1.55, all P<0.001).
UNASSIGNED: Synthetic MRI generates morphologic magnetic resonance (MR) images with diagnostically acceptable image quality in bladder tumors, especially T1-weighted images with high image contrast of tumors relative to urine. Further technological improvements are needed for synthetic MRI to reduce noise. Combined with T1, T2, and proton density (PD) quantitative data, synthetic MRI has potential for clinical application in bladder tumors.